I've seen two timelines published so far regarding Swine Flu, and I'd guess more will follow.

It may be interesting to keep copies of them together in one thread so we can mentally start piecing together a bigger picture than any one timeline will provide (and, like all written history, every individual's timeline will reflect a point-of-view).


MomCares 

Timeline from Biosuveillance -- Veratect
http://biosurveillance.typepad.com/...-of-events.html


April 2

Local media source Imagen del Golfo reported that state health officials recorded a 15% increase in disease over an unspecified period in the highland areas of Veracruz, which includes La Gloria. The increase was primarily due to higher levels of upper respiratory disease and gastroenteritis. Specifically, officials noted an increase in pneumonia and bronchial pneumonia cases. Health officials attributed the increase to seasonal climate changes.

April 6

Veratect reported local health officials declared a health alert due to a respiratory disease outbreak in La Gloria, Perote Municipality, Veracruz State, Mexico. Sources characterized the event as a "strange" outbreak of acute respiratory infection, which led to bronchial pneumonia in some pediatric cases. According to a local resident, symptoms included fever, severe cough, and large amounts of phlegm. Health officials recorded 400 cases that sought medical treatment in the last week in La Gloria, which has a population of 3,000; officials indicated that 60% of the town’s population (approximately 1,800 cases) has been affected. No precise timeframe was provided, but sources reported that a local official had been seeking health assistance for the town since February.

Residents claimed that three pediatric cases, all under two years of age, died from the outbreak. However, health officials stated that there was no direct link between the pediatric deaths and the outbreak; they stated the three fatal cases were "isolated" and "not related" to each other.

Residents believed the outbreak had been caused by contamination from pig breeding farms located in the area. They believed that the farms, operated by Granjas Carroll, polluted the atmosphere and local water bodies, which in turn led to the disease outbreak. According to residents, the company denied responsibility for the outbreak and attributed the cases to "flu." However, a municipal health official stated that preliminary investigations indicated that the disease vector was a type of fly that reproduces in pig waste and that the outbreak was linked to the pig farms. It was unclear whether health officials had identified a suspected pathogen responsible for this outbreak.

Local health officials had implemented several control measures in response to the outbreak. A health cordon was established around La Gloria. Officials launched a spraying and cleaning operation that targeted the fly suspected to be the disease vector. State health officials also implemented a vaccination campaign against influenza, although sources noted physicians ruled out influenza as the cause of the outbreak. Finally, officials announced an epidemiological investigation that focused on any cases exhibiting symptoms since 10 March.

This information was available in our web portal to all clients, including CDC and multiple US state and local public health authorities.

April 16

Veratect reported the Oaxaca Health Department (SSO) indicated that an unspecified number of atypical pneumonia cases were detected at the Hospital Civil Aurelio Valdivieso in Reforma, Oaxaca State, Mexico. No information was provided about symptoms or treatment for the cases. NSS Oaxaca reported that rumors were circulating that human coronavirus was spreading at the hospital; sources did not provide any response to these statements from the hospital or health officials.

Laboratory samples were sent to Mexico City for analysis; results were expected to be released sometime next week. According to NSS Oaxaca, health officials had intensified preventive measures aimed at mitigating further spread of the disease. Sources reported that the SSO also implemented a sanitary cordon around the hospital.

This information was pushed to CDC and several US state and local public health authorities in an email alert notification provided by Veratect.

April 20

Veratect was urgently asked to provide access to the VeraSight Global platform on 20 April by a client in the US public health community, and indicated they had received word from their counterparts in Canada that Mexican authorities had requested support. This client speculated whether notification of all southern U.S. border states’ public health authorities should be done and were confused as to why the CDC had not issued an advisory. Veratect contacted the CDC Emergency Operations Center to sensitize them about the situation in Mexico. CDC indicated they were already dealing with the crisis of recently detected H1N1 swine influenza in California and possibly Texas.

April 21

Veratect reported the Oaxaca Health Department (SSO) confirmed two adults died from atypical pneumonia at the Hospital Civil Aurelio Valdivieso in Oaxaca, Oaxaca State, Mexico. One of the cases was a 39-year-old female; the other case was an adult male of unspecified age. After the deaths, the hospital established a quarantine in the emergency room due to initial concerns that avian influenza was responsible for the cases. However, the SSO subsequently stated that neither avian influenza nor coronaviruses, including that which causes severe acute respiratory syndrome (SARS), were the source of infection. Additionally, the SSO denied the cases represented an epidemic. According to local sources, the SSO indicated that the atypical pneumonia cases were caused by an unspecified bacterial pathogen and were treatable with antibiotics. Sources indicated a total of 16 additional patients exhibited signs of respiratory infection; none of these patients exhibited complications.

Veratect sources indicated the 39-year-old female was treated at the hospital for five days before dying on 13 April. This case was reportedly immunocompromised; in addition to acute respiratory symptoms, she also had diabetes and diarrhea. The SSO contacted 300 people that had been in contact with the woman; sources stated that between 33-61 contacts exhibited symptoms of respiratory disease, but none showed severe complications. The SSO characterized the incident as an "isolated case;" they noted that over 5,000 cases of pneumonia occur annually in Oaxaca.

Another local source reported the SSO launched surveillance measures in the former residential areas of the two fatal cases and in other targeted geographic areas. No additional information was provided regarding the second fatal case at the hospital.

Veratect reported that the Oaxaca State Congress Permanent Committee on Health had undertaken an investigation into the cases. The committee inspected the Hospital Civil Aurelio Valdivieso on 20 April. The director of the medical school at the University Autónoma "Benito Juárez" de Oaxaca (UABJO), along with other medical academics, publicly requested that national health authorities investigate the cases of atypical pneumonia. No information was provided indicating that national health authorities plan to investigate the matter. The director of the medical school also requested the SSO furnish evidence showing that the cases were negative for avian influenza, SARS, and other severe pathogens; his request was echoed by readers commenting on an online user forum.

Veratect also reported the National Ministry of Health issued a health alert due to a significant increase in influenza cases during the spring season in Mexico. Officials indicated that there have been 14 influenza outbreaks throughout the country. The most heavily affected states are Baja California, Chihuahua, Distrito Federal (Mexico City), Hidalgo, Tlaxcala, and Veracruz. Local case counts were not provided.

Officials stated that 4,167 probable cases of influenza, 313 of which were confirmed, have been reported throughout the country in 2009. Case counts for suspected and confirmed influenza cases have tripled in 2009 as compared to the equivalent time period in 2008. The National Institute of Respiratory Diseases recorded two fatal cases of influenza in 2009, but specific dates and locations were not provided.

Health officials stated they were unsure precisely why the incidence of influenza had increased. However, they believed the increased presence of influenza B, in combination with influenza A, was a contributing factor. In response, officials advised anyone exhibiting influenza symptoms to avoid self-medication and seek medical care immediately. Officials had also enhanced epidemiological surveillance for influenza. Lastly, health officials had focused efforts on providing antiviral medications and influenza vaccinations to the most vulnerable segments of the population. According to the Mexican Ministry of Health, 44.3% of the national population was vaccinated against influenza in 2005-2006.

Veratect sensitized the International Federation of Red Cross who in turn requested broader access be provided to the Pan-American Disaster Response Unit (PADRU). Veratect moved to notify several US state and local public health authorities, providing the caveat the situation in Mexico remained unclear due to pending laboratory results. Veratect reached out to World Health Organization (WHO) operations, informing them the Veratect team was on an alert posture and available for situational awareness support. They indicated they and their subordinate, the Pan American Health Organization (PAHO) were now aware of the situation but had no further information. Veratect also extended contact to the British Columbia Center for Disease Control and offered assistance in tracking the events in Mexico. All contacts indicated laboratory results were pending.

April 22

Veratect reported the Oaxaca Health Department (SSO) indicated 16 employees at the Hospital Civil Aurelio Valdivieso in Oaxaca, Oaxaca State, Mexico had contracted respiratory disease. However, the SSO denied these cases were connected to the recently identified cases of atypical pneumonia at the hospital. No information was provided indicating how many employees work at the hospital or whether the number of respiratory disease cases was higher than average. The source reported that "fear" persisted among hospital physicians concerning the possible presence of a deadly bacteria or virus circulating in the hospital. One anonymous hospital employee criticized hospital management as "unfair" for not providing clear information regarding the first fatal atypical pneumonia case.

An additional source reported the cause of the atypical pneumonia cases remained unknown; it stated that bacteria or virus could have caused the cases. In contrast, according to an 18 April report, the SSO indicated that the atypical pneumonia cases were caused by an unspecified bacterial pathogen and were treatable with antibiotics. The reason for this discrepancy was unclear at this time.

The Instituto Mexicano del Seguro Social (IMSS), a national health entity, had now joined the SSO in responding to the cases; reports did not indicate the Mexican National Ministry of Health had joined in the response efforts. The IMSS extended the sanitary cordon surrounding the hospital. Patients exhibiting flu-like symptoms would be sent to the hospital’s epidemiology department for further study. IMSS instructed physicians to hospitalize respiratory disease patients immediately if they meet certain standards for severity of symptoms. Lastly, the hospital’s emergency room would remain closed for an additional 15 days so that cleaning and preventive disinfection could be carried out.

Veratect also reported the Mexican Ministry of Health indicated that an "unusual" outbreak of laboratory-confirmed influenza caused five deaths from 17-19 April 2009 in Mexico City, Mexico. The deaths occurred at the following three hospitals: el Hospital de la Secretaría de Salud (2), el Institute Nacional de Enfermedades Respiratorias (2), and el Hospital Ángeles del Pedregal (1). According to unofficial sources, the fatal case count was higher than that provided by officials. There were currently 120 influenza cases hospitalized throughout Mexico City. National health officials indicated that influenza vaccines were sold out in Mexico City and that they were attempting to acquire additional supplies of the vaccine.

At this point, the Mexican Health Secretary reportedly stated there was an influenza epidemic in Mexico City and throughout the rest of the county. In response to the cases, the official stated health authorities would launch a public awareness and vaccination campaigns. He stated that 400,000 vaccines would be administered, primarily to medical staff; it was unclear whether these efforts would be focused on Mexico City or any other geographic area. Health officials also ordered the provision of special masks, gloves, and gowns for medical personnel that were in contact with influenza cases.

A total of 13 fatal cases of influenza were reported in Mexico City in the past three weeks. However, several other media sources reported that the 13 deaths were recorded since 18 March 2009; the reason for this discrepancy was unclear. Sources reported a total of 20 fatal cases of influenza throughout Mexico over the disputed timeframe. The other cases were located in San Luis Potosí (4), Baja California (2), and Oaxaca (1). The Director of Epidemiology at the National Center for Epidemiological Surveillance and Disease Control characterized the outbreak as "quite unusual."

No information was provided indicating that the strain of influenza itself was unusual. Rather, several sources indicated that it was "unusual" to record this many fatal influenza cases during this time of year. Influenza cases normally peak from October to February, while these cases had occurred during Mexico’s spring season.

Canada announced a national alert for travelers returning from Mexico with respiratory disease, beginning a campaign of public media announcements. Potentially ill contacts were identified returning from Mexico and isolated in Canada. Internet blogs begin to spin up. CDC indicates concern about the events unfolding in Mexico. Veratect sensitizes the US community physician social network managed by Ozmosis.

April 23

Veratect reported the Secretary General of the Oaxaca Ministry of Health Workers Union confirmed that a doctor and a nurse from the Hospital Civil Aurelio Valdivieso in Oaxaca, Oaxaca State, Mexico were under observation for suspected "atypical" pneumonia. This contradicted statements made by the Oaxaca Health Department (SSO) on 22 April that 16 hospital employees contracted respiratory disease, but none of the cases exhibited atypical pneumonia.

The union official stated that a review by the Oaxaca State Board of Medical Arbitration indicated that the hospital faced serious difficulties caused by overcrowding; he stated that overcrowded conditions created a "breeding ground" for the spread of various epidemics. According to the official, the hospital has 120 beds but the number of patients hospitalized had at times surpassed 240.

Other sources reported that the Department of Livestock, Fisheries, Rural Development, and Feed (SAGARPA) declared on 20 April that Oaxaca, Mexico was free of avian influenza. SAGARPA stated that authorities should remain vigilant in monitoring for the disease among birds.

... snip

Veratect assesses the situation and notes the following:

Affected areas:

Oaxaca, Distrito Federal, San Luis Potosí, Baja California

Distance to nearest international airport:

• Oaxaca airport, located approximately 150 miles from Reforma, is connected via non-stop air traffic to Houston
• Mexico City (Distrito Federal) airport is connected via non-stop air traffic to many cities in the US, Canada, Europe and Latin America, with the most outbound traffic to Los Angeles, Frankfurt, Houston, Dallas, and Amsterdam
• San Luis Potosí airport is connected via non-stop air traffic to Dallas and Houston
• Mexicali airport in Baja California is connected via non-stop traffic to Los Angeles
• Veracruz airport is connected via non-stop air traffic to Houston

Large mass gatherings:

Semana Santa (April ~April 3 – 12, Palm Sunday to Easter Sunday), which is Mexico’s second largest holiday. Mexico’s population is approximately 90% Catholic, which results in substantial population migration patterns during this time period. For instance, in Ixtapalapa (in Mexico City), one million people visit for Semana Santa. Other well-known sites for the holiday include Pátzcuaro, San Cristobal de las Casas (Chiapas), and Taxco. Veratect notes substantial population migration has just occurred that could facilitate the spread of respiratory disease.

Civil Unrest:

The recent surge in organized crime and drug-related violence in Mexico, including homicides, kidnappings, extortion, and theft, has disproportionately impacted Mexican states along the Pacific Coast and U.S.-Mexico border. This factor may confound situational awareness of respiratory disease in Mexico and contribute to problems in epidemiological investigation and response measures. Baja California is one of five states within this region that currently accounts for more than 75 percent of Mexico's drug-related homicides, and has recorded high levels of drug seizures and police corruption cases. Veracruz, a state with high drug cartel activity in the Gulf of Mexico, has recorded little violence, while the state of Oaxaca to the southwest, recently recorded the assassination of a political party leader. Mexico City, in the center of the country, recently arrested a major drug cartel leader, and recorded few homicides this month. The levels of unrest in Hidalgo, San Luis Potosi, and Tlaxcala, however, are very low, and have not reported a single homicide related to organized crime in the past month.


Veratect issues notification to additional public health authorities in two states. Veratect reaches out to the Pan American Health Organization emergency operations team but is unable to establish contact. Veratect notes no publicly available English language reporting from ProMED, HealthMap, FluNET, CDC, ECDC, or WHO about the unfolding events in Mexico. Many of Veratect’s clients, including Canadian, ask why an alert has not been issued by the US to sensitize their healthcare community.

April 24

Veratect continues to process a dramatic increase in reporting on the situation in Mexico.

WHO requests access to the Veratect system. Veratect is aware of laboratory samples from Mexico are positive for “swine flu” H1N1, a novel virus. World media are now aware of the situation in Mexico. CDC issues a press statement, as does WHO. 

Timeline from Helen Branswell
http://www.google.com/hostednews/ca...0C2bUjQ2ilA53Mg


1998:

An H1N1 swine flu virus containing swine, avian and human genes is recognized in pig populations in North America. This virus will later be recognized as a parent of the new swine flu.

2009:

March 31 - A clinical trial designed to assess the efficacy of a new rapid diagnostic test for influenza finds an untypeable flu virus in a sample from a person from the San Diego area. Public health is alerted and the virus is sent for testing in Wisconsin and later to the U.S. Centers for Disease Control.

April 17 - The CDC informs the World Health Organization it has found a case where an H1N1 swine flu virus infected a person in California. The virus is similar to the triple reassortant but with two swapped genes. Human infection with animal flu viruses signals a pandemic threat and WHO alerts member states.

April 17 - The head of Mexico's national microbiology lab emails Dr. Frank Plummer, head of Canada's national lab in Winnipeg, asking for help figuring out what is behind outbreaks of severe respiratory disease in parts of Mexico. Plummer offers assistance.

April 20 - The Public Health Agency of Canada warns quarantine services to be on the lookout for sick travellers returning from Mexico.

April 21 - The CDC issues an advisory revealing it has found two human swine flu cases in California. The WHO says it is watching.

April 22 - Specimens from Mexico arrive at the Winnipeg lab shortly before lunch. Within 24 hours researchers there realize at least some of the Mexican cases are human infections with the H1N1 swine flu virus.

April 23 - The CDC says they've found seven swine flu infections, in California and Texas.

April 24 - Mexico informs the WHO the Winnipeg lab has confirmed H1N1 swine flu is causing disease in Mexico.

April 26 - Officials in Nova Scotia and British Columbia announce Canada's first swine flu cases.

April 27 - The WHO raises the pandemic alert level to Phase 4 for the first time since the scale was created. Five countries have cases.

April 29 - The WHO raises the pandemic alert level to Phase 5, one away from a pandemic. It says the virus is spreading from person to person in both Mexico and the United States. 

MomCares Timeline additions

I'll add a couple dates related to specific early cases from Mexico that I don't think are in either of the above timelines...


April 2 -- Edgar Hernandez, a boy who subsequently makes a full recovery, falls ill. He lives in the small town of La Gloria, in Veracruz province, five miles downwind of a vast pig farm identified a potential source of the outbreak. He is (so far) the earliest confirmed case in Mexico, though there were other suspect cases in La Gloria as early as February.

April 8 -- Maria Adela Gutierrez, a 39-year-old census-taker (or tax inspector?) in Oaxaca, is admitted to a local hospital suffering acute respiratory problems, exacerbated by diabetes and severe diarrhoea.

April 13 -- Maria Adela Gutierrez (above) becomes the first confirmed swine flu death. It is believed that her job, which involved going door-to-door, may have made her a super-spreader... putting her in contact with at least 300 unsuspecting members of the public when the disease was at its most virulent.

April 13 -- Gerardo Leyva Lolis, 39-year-old bricklayer, falls ill in Xonacatlan. He visits a local clinicand gets a shot.

April 14 -- Gerardo Leyva Lolis (above) makes a 40-mile bus trip to Mexico City, taking subways to work despite a nasty cough.

April 19 -- Gerardo Leyva Lolis was having trouble breathing and had an irregular heartbeat, so his family takes him to the nearby city of Toluca, where the poor can get discounted care at a large public hospital.

April 20 -- By 8 a.m. the next day, Gerardo Leyva Lolis is dead.


MomCares 

Had we ever heard this part of the story before?

It would be very interesting to know about the person who the March 31 sample came from. Was this March 31 sample the one confirmed by CDC as swine flu on April 17? If so, why did it take so long to get results? Did the person have any connection to either La Gloria or Oaxaca?


MomCares 

Here's another timeline...

A timeline of events in the swine flu outbreak
By The Associated Press – 1 day ago
http://www.google.com/hostednews/ap...3dIUmwD97RPT800


A timeline of events in the swine flu outbreak:

_ December 2005 to January 2009: The Centers for Disease Control and Prevention receives reports of 12 cases of human infection with swine flu. Five of these 12 cases occurred in patients who had direct exposure to pigs and six reported being near pigs. Exposure in one case is unknown.

_ March 28: Believed to be the date of the earliest onset of the swine flu cases in the U.S., Dr. Nancy Cox of the CDC said in an April 23 press briefing.

_ April 2: A 4-year-old boy contracted the virus before this date in Veracruz state, Mexican Health Secretary Jose Angel Cordova later said citing test results. A community in Veracruz has been protesting pollution from a large pig farm.

_ April 6: Local health officials declare a health alert due to a respiratory disease outbreak in the Mexican town of La Gloria in Veracruz state. Health officials record 400 cases of people who sought medical treatment in the previous week in the town. About 60 percent of the town of 3,000 are affected.

_ April 17: CDC determines that two children in adjacent counties in southern California had illnesses caused by infection with swine flu. Both children became sick in late March.

_ April 22: CDC confirms three additional cases of swine flu in California and two in Texas, near San Antonio.

_ April 22: The Oaxaca Health Department indicates that 16 employees at the Hospital Civil Aurelio Valdivieso have contracted respiratory disease.

_ April 24: Mexico's Minister of Health confirms 20 deaths from swine flu, but 40 other fatalities were being probed and at least 943 nationwide were sick from the suspected flu. Mexico City shuts down schools, museums, libraries, and state-run theaters across the capital.

_ April 26: The number of confirmed cases in the U.S. climbs to 20 in five states. Mexico reports suspect clinical cases have been reported in 19 of the country's 32 states. Canada confirms six cases.

_ April 27: The World Health Organization raises its pandemic alert status to Phase 4, meaning there is sustained human-to-human transmission of the virus causing outbreaks in at least one country.

_ April 28: Cuba suspends flights to and from Mexico, becoming the first country to impose a travel ban. Argentina suspends flights from Mexico for five days. 

Here are the two pieces of info in the AP timeline that seem new to me...

Again the same questions as above...

It would be very interesting to know about the children who the March 31 sample(s) came from. Was this March 31 sample the one confirmed by CDC as swine flu on April 17? If so, why did it take so long to get results? Did the children have any connection to either La Gloria or Oaxaca?


MomCares 

These dates are early enough that, IMHO, they deserve a place on our timeline...


April 5 -- Family of Patient X (toddler from Mexico City with underlying health problems) spends three nights in Houston, including shopping at The Galleria mall.

April 8 -- Patient X is hospitalized..

April 14 -- Patient X moved to Texas Children's Hospital in Houston.

April 27 -- Patient X dies.


MomCares 

Several things about the above dates are interesting.

1) This is a very early case, who may have spread virus in several parts of Texas.

2) The child was apparently well enough to be out-and-about up to a day before being hospitalized.

3) After 2.5 weeks of presumably-intensive hospital intervention, in hospitals that were NOT overrun with flu cases, he couldn't be saved.

Sad, and food for thought.


MomCares 

Oooo... I just found a more official version of my timeline above (Post #8) with a few more details...

FACTBOX - Timeline of 1st US swine flu death in Texas
Wed Apr 29, 2009 6:47pm BST
http://uk.reuters.com/article/UKNew...E53S6EY20090429


Following is a chronology of key dates in the case, as provided by Texas state health officials:

April 4 - A 22-month-old boy travels with his family to Matamoros, Mexico, from Mexico City on a commercial flight, to visit relatives in Brownsville, Texas, just across the border.

April 8 - boy develops fever and influenza-like symptoms.

April 13 - boy admitted to Brownsville area hospital.

April 14 - medical transport service transfers boy to Texas Children's Hospital in Houston, which has a world-class medical centre.

April 27 - boy dies of underlying problems associated with pneumonia.

April 29 - U.S. Centers for Disease Control and Prevention confirm that boy had swine flu, making him the first confirmed U.S. death of the disease.

(Sources: Texas Department of State Health Services, Houston Department of Health and Human Services, Texas Children's Hospital) 

... and here's history according to Nature...
http://www.nature.com/news/2009/090...s.2009.416.html


30 April 2009: Austria, Switzerland and the Netherlands join the WHO list of countries with confirmed cases. The agency also announces it will refer to the virus not as swine flu but as influenza A(H1N1).

29 April 2009: The WHO raises pandemic level alert to phase 5, "a strong signal that a pandemic is imminent". First swine-flu death outside Mexico reported as a baby dies in Texas. Germany joins European countries with H1N1 and confirms three swine flu cases. The WHO confirms 7 more cases in Canada, bringing the total number there to 13.

28 April 2009: Seven countries are now reporting confirmed cases of H1N1 swine flu: the United States, Mexico, Canada, New Zealand, the United Kingdom, Israel and Spain.

27 April 2009: Canada reports six cases of swine flu and Spain reports one. In the United States 40 people have flu confirmed. In Mexico 26 cases are confirmed, with 7 deaths resulting. Estimates for the true number of deaths hover around 80.

The WHO raises pandemic alert level to 4 having confirmed human-to-human transmission able to cause 'community-level outbreaks'. "Phase 4 indicates a significant increase in risk of a pandemic but does not necessarily mean that a pandemic is a forgone conclusion," says the organisation.

25 April 2009: WHO director-general, Margaret Chan calls the flu problem "a public health emergency of international concern ".

21 April 2009: CDC laboratories confirm two cases in California. Three additional cases confirmed the next day, with two more in Texas added the day after.

28 March 2009: Earliest onset date of swine flu reaching the United States, according to the CDC.

18 March 2009 : Federal District of Mexico begins to pick up cases of swine flu. 

I posted this in another forum but might as well share my thoughts here too.


Think about the following time line and the evidence for how many cases are not in the official count. When this is over there is going to be an incredible amount of epidemiological data to analyze. The public is so expecting instant doom or there must be no threat. They seem to have little clue about the implications of how fast this strain has spread or about what such a pandemic should look like through observation tools never before seen in history.

I've posted links to this data or other people have in past posts so I'm not going to put cites for all the facts here.

The first inkling of this new strain entering the population occurred in early March when a town in Mexico, La Gloria, experienced widespread serious upper respiratory infections and 3 kids died. A small number of samples were recovered after the number of cases subsided and were positive for the new flu strain.

A woman with a job going door to door in the vicinity of La Gloria developed pneumonia with the onset of illness around the first week in April. She eventually died in Mexico City on April 13th.

An amplifying event occurred with a Mexican holiday, Semana Santa, the week of April 5th to the 12th when many people in Mexico travel in Mexico.

A second amplifying event probably took place during Spring breaks for US colleges when lots of students travel to Mexico and return to mix with large clusters of fellow students. This year's breaks began the week of February 16-20. The largest number of colleges were off March 16-20, the second biggest group, March 9-13 and the last break was April 6-10, 2009. Perhaps only the last week or two of travelers were affected.

There is continual travel between Mexico and the US because we have such a large overlapping population.

Swine-Origin Influenza A (H1N1) Virus Infections in a School --- New York City, April 2009

Per WHO's last update, "30 April 2009 -- The situation continues to evolve rapidly. As of 17:00 GMT, 30 April 2009, 11 countries have officially reported 257 cases of influenza A (H1N1) infection."

Now there are a couple important things to point out here. One is the short time span. In 2 months or maybe 2.5 or so this infection went from the first patient to world wide early phase pandemic. That's really really fast.

Compare that to SARS which festered in Guangdong China for 4 months (Nov, 2002 to Feb, 2003), broke out into Hong Kong in March and spread from Hong Kong to 18 countries in April but only Canada and the US had clusters of cases outside SE Asia. The other countries merely had citizens who were infected elsewhere and became ill after arriving home.

In addition, with SARS, most cases outside of China could be connected.

The second important thing to consider is how many people are really infected here. The NY school came to the attention of health authorities because so many kids were ill at the same time, ("222 students visited the school nursing office and left school because of illness"). Only 7 were tested, ("DOHMH staff members collected nasopharyngeal swabs from five newly symptomatic students identified by the school nurse and four newly symptomatic students identified at a nearby physician's office") That doesn't mean only 44 of the 222 kids had swine flu. By case definition, most if not all of them met the definition of a probable case.

So on April 20th there were 10 sick kids and by 3 days later the total had reached 222 out of a population of 3,000.


To anyone who looks carefully at this evidence and understands the epidemiology we are seeing here, this organism is incredibly contagious. The absence of known exposure sources in many cases suggests many undetected infections. The speed of spread is unusual even for influenza.


We still don't have much of a clue how many serious illnesses we are going to see. It could be that because we have never tracked seasonal flu in this much detail, that there are many more mild cases of influenza during flu season than are typically recognized. To conclude nothing is going to come of this in the way of serious illness is naive.

At a minimum staffing shortages and closed businesses are going to affect lots of people. I wrote a sick leave policy yesterday and I started adding it up and the hospital I was writing it for is going to have some serious issues. If you are exposed to sick family members, you have to stay home. If the schools close some workers will have child care issues. If workers are ill, they can't return for 7 days even if they feel better. This is going to be a mess even if only a few serious cases occur.

There is already a local shortage of both Relenza and Tamiflu if you want to buy some to dispense from your office practice. I'm not sure how the supply is for filling individual prescriptions. Public health is triaging prophylaxis and treatment. If you are seriously ill or have a high risk condition, you get treated. If it's mild or you've been exposed but you don't have specific risks, no prophy for you. I think health care workers can get prophylaxis, but not if there is none to be had. The Feds are being quite stingy. I say they didn't stockpile enough. Hopefully this pandemic will be a nice dry run to see what problems we might encounter when a more lethal phase or strain comes around. 

I'm actually quite glad that they aren't treating everyone with Tamiflu. Don't know if it is too smart to put huge evolutionary pressure to this thing now that we do know that it has relatively mild characteristics in most cases, at least for now.

I've read some studies suggesting that up to 1-1.5 % infected rate, people should be treated with secondary drug of choice (in this case, Relenza) or shouldn't be treated at all (or as minimal as possible). So that when virus strikes the most, the strain that is dominant isn't resistant to primary medicine (in this case, Tamiflu) 

Agree about it being best not to throw too much Tamiflu around too early, both to minimize pressure towards resistance and to preserve supplies for high-risk folks (though of course we don't yet know enough to be sure who's most at risk).

Also agree that there's little doubt that this bug is highly contagious AND it seems able to dominate over seasonal strains. Here's an insider's view on that (snip from another thread)...
 

CIDRAP's latest update contained one date I don't think we've heard before...

March 17 -- The first {recorded} person with swine flu in Mexico falls ill {per an MMWR Dispatch from the Centers for Disease Control and Prevention (CDC).}


Nothing more was said about where this case was located.

It is interesting that this is only 10 days before disease onset of the first recorded US case on March 28 (per Post #6 above).

My bet is there were earlier cases.


MomCares 

Outbreak of Swine-Origin Influenza A (H1N1) Virus Infection --- Mexico,
March--April 2009
http://www.cdc.gov/mmwr/preview/mmw...mm58d0430a2.htm


In March and early April 2009, Mexico experienced outbreaks of respiratory illness and increased reports of patients with influenza-like illness (ILI) in several areas of the country. On April 12, the General Directorate of Epidemiology (DGE) reported an outbreak of ILI in a small community in the state of Veracruz to the Pan American Health Organization (PAHO) in accordance with International Health Regulations. On April 17, a case of atypical pneumonia in Oaxaca State prompted enhanced surveillance throughout Mexico. On April 23, several cases of severe respiratory illness laboratory confirmed as swine-origin influenza A (H1N1) virus (S-OIV) infection were communicated to the PAHO. Sequence analysis revealed that the patients were infected with the same S-OIV strain detected in two children residing in California (1). This report describes the initial and ongoing investigation of the S-OIV outbreak in Mexico.

Enhanced Surveillance

On April 17, in response to the increase in reports of respiratory illness, DGE issued a national epidemiologic alert to all influenza-monitoring units and hospitals (Table 1). The alert asked hospitals to report all patients with severe respiratory illness and recommended collection of diagnostic respiratory specimens from these patients within 72 hours of illness onset. On April 18, DGE staff visited 21 hospitals throughout the country to confirm the apparent increase in illness incidence.

After laboratory confirmation of S-OIV infection on April 23, DGE developed case definitions. A suspected case was defined as severe respiratory illness with fever, cough, and difficulty breathing. A probable case was defined as a suspected case in a patient from whom a specimen had been collected and tested positive for influenza A. A confirmed case was defined as a probable case that tested positive for S-OIV by real-time reverse--transcription polymerase chain reaction (RT-PCR). Health-care officials were contacted and asked to provide retrospective and ongoing data for persons having illness consistent with these case definitions and seeking care on or after March 1.

During March 1--April 30, a total of 1,918 suspected* cases were reported, including 286 probable and 97 confirmed cases (Figure). A total of 84 deaths were reported. A majority of case-reports were for hospitalized patients, reflecting the concentration of surveillance efforts within hospitals. However, DGE also received reports from sites conducting routine seasonal influenza surveillance of patients with ILI. Of 1,069 patients with suspected and probable cases for whom information was available, 755 were hospitalized, and the remaining 314 were examined in outpatient settings or emergency departments. Suspected or probable cases were reported from all 31 states and from the Federal District of Mexico. The four areas with the most cases were Federal District (213 cases), Guanajuato (141), Aguascalientes (93), and Durango (77). In other states, the number of suspected or probable cases ranged from two to 46. Suspected and probable cases were identified in all age groups. Mexico routinely monitors seasonal influenza in a network of outpatient facilities throughout the country. Fifty-one influenza A positive specimens from six states were collected during January 4--March 11 in this surveillance network. All of these specimens tested negative for S-OIV at CDC.

... snip

As of April 30, DGE surveillance activities, focusing on patients with severe respiratory disease, had identified 97 patients with laboratory-confirmed S-OIV infection, including seven persons who had died. The first of the 97 patients reported onset of illness (any symptom) on March 17, and the most recent patients reported onset on April 26. 

I just found a snip of interesting info about Ms. Gutierrez...

MomCares 

About the students in Queens:

This confused me, because I thought they went to Cancun.
From WCBSTV we learn:

Question remains why there are not more people ill in the US. 

It was already obvious that Edgar Hernandez was not patient zero, because he couldn't have infected the March 28 California confirmed case. Also infecting the toddler from Mexico City would have been somewhat difficult. 

Agreed, it was obvious.

I think it's equally unlikely that whoever became ill on March 17 was patient zero, but we may never know since the earlier pediatric deaths in La Gloria will not be exhumed and I don't think there are any earlier samples.


MomCares 

... snip from another thread

Alpuche: In the last part of the outbreak in La Gloria, children started having symptoms April 1. They took the samples April 3. They sent the samples to the public health state lab, and they were processed April 4. These arrived at my lab on April 8.

Science: What were the positive ones?

Alpuche: They only identified three influenza strains at the end of the period. One turned out be H3N2. The other was A, but it was not heartening. Here at our lab, we were considering that it could be H1, but it looked indeterminate. To be honest, we were not able to type it. And then we had a B.

Science: The one that you weren't able to type, did you send that anywhere else? Were you concerned that you couldn't type it?

Alpuche: At that moment, we didn't have any information about the untypeable A's that they saw in the California children. 

From TimesDispatch :

Above Veratect claims that on April 16:

Next day April 17 the CDC informed the WHO on their swine flu find. Above it is mentioned: "and the WHO alerts member states". The question is: what else did they do in the week that followed.

More on this issue here . 

Pablo Kuri, an epidemiologist advising Cordova, told The Associated Press on Sunday that tests have confirmed a swine flu death in Mexico City on April 11, two days earlier than what had been believed to be the first death. 

Interesting rundown of some events on the timeline...

http://www.washingtonpost.com/wp-dy...ST2009050202398

... snip

A Fortuitous Test

The medical detective work that unearthed the 2009 outbreak of swine-origin influenza A (H1N1) -- more commonly known as swine flu -- began with a bit of happenstance.

On March 30, a 10-year-old boy in Southern California developed a cough and fever. Normally, doctors wouldn't have bothered testing for the flu; they would have given him medicine and sent him home.

But the Naval Health Research Center in San Diego was participating in a clinical trial of new, 30-minute flu tests, so they took a nasal swab and tested it the next day.

The boy had a flu strain that the virologists, skilled at identifying the seasonal flu, didn't recognize. Following the study protocols, they shipped the specimen to a research lab at the Marshfield Clinic in Wisconsin, which also concluded that the boy, who would become known as Patient A, was infected with an unrecognizable influenza virus. Next it was sent to the state health lab.

Since the 2003 bird flu outbreak, the public health community has been on the lookout for problematic new viruses. When the boy's nasal swab reached the Wisconsin state lab shortly after 3 p.m. on April 10, just as the office was closing for the Easter weekend, lab chief Peter Shult asked whether it was a high-risk case.

"The concern always is, could this be avian?" he said. "You are always worried that one of those might sneak in."

Once Shult learned that the specimen was from a child who hadn't been out of the country and had recovered from the mild illness, he decided the test could wait. He suspected the youngster had contracted swine flu, rare but not unheard of, he said later.

Swine flu in pigs is common, but only rarely does it spread to humans. Nationwide, health officials see a few cases each year, with the last major public health crisis occurring in 1976, when 40 million people were vaccinated after an Army recruit died of the illness in New Jersey. People cannot be infected by eating pork. Twice on April 13, Shult ran the lab tests, confirming that what he had on his hands was an influenza strain he could not pinpoint. "We sent it immediately to CDC," he said.

As that first San Diego sample made its way to Atlanta, the naval lab got its second curious case, a 9-year-old girl. Again, the scientists diagnosed influenza but couldn't be more specific. The only thing they knew: The child's flu was not the normal variety.
ad_icon

This time, the specimen was shipped to Atlanta, and Patrick Blair, the director of the Navy lab, alerted the CDC that something was amiss. CDC officials paid attention because Blair was known in the medical detective world, having spent much of his career as a virus hunter in Indonesia.

"That's the trick with catching something early," said Michael Shaw, the CDC's associate director for laboratory science. "You need a person in the field with a good eye and a bit of paranoid suspicion to send it along."

Unidentifiable Samples

As Shult ran tests in Wisconsin and Blair puzzled over the second atypical virus to pass through his lab in less than a week, Mexican authorities grappled with a late-season wave of flulike illness.

At the White House, President Obama prepared for his first trip to Mexico, on April 16, with advance teams already on the ground.

CDC analysts scour daily for early warning signs of a disease outbreak or natural disaster. With computer search tools, they scan news reports, online blogs and the data that pours into the operations center.

"We're picking up thousands of signals every day," said Scott F. Dowell, head of global disease detection at the CDC. "The challenge is in interpreting them."

On April 13, the Mexican Health Ministry sent the CDC an e-mail describing a cluster of "unexplained respiratory illness," Dowell said. But the reports were contradictory, and because the majority of respiratory illnesses are unexplained, Dowell said it was difficult to assess what was happening thousands of miles away.

The next day, the CDC lab got the specimen from Patient A, the 10-year-old boy, and a day later identified it as the new H1N1 virus.

Interesting but not stunning, thought Daniel B. Jernigan, Cox's deputy in the flu division. As the person overseeing the rapid-flu-test project in San Diego and other sites, Jernigan makes his living tracking influenza cases. He had seen a dozen swine flu cases in recent years, most often a child who had visited a petting zoo or a farmer who had come in contact with a sick pig.

"The kid gets a fever, mom doesn't feel too good, they take some medicine, and it's all over," Jernigan said. The swine influenza, in other words, typically dies out quickly.

When the second San Diego specimen arrived and it, too, was determined to be swine influenza, Jernigan's team started digging. In the lab, "we blast-sequenced it against our entire pig laboratory," he said, describing the hundreds of swine virus samples the CDC has collected over the years. "There was no match."

Despite their confidence in Blair, they wondered whether a contaminant had landed in the Navy lab.

Then came the call from Texas -- two teenage boys in Guadalupe County with an unrecognizable flu virus.
ad_icon

Then San Diego. Another influenza virus they couldn't identify.

By Thursday, April 16, as Obama's Air Force One landed at Benito Juarez International Airport in Mexico City, CDC officials were struggling to "connect the dots," as Cox put it. She called Mexico, requesting specimens.

"We thought there might be a possibility but not necessarily be a connection between the situation in California and what was unfolding in Mexico," she said.

Unbeknownst at the time, a member of Obama's advance team -- dispatched to Mexico on April 13 -- had contracted the swine flu and brought it home to the Washington area.

Making the Connection

Over the weekend of April 18, CDC officials began drafting an urgent public health dispatch describing a pair of novel swine flu cases in the San Diego area. In a Saturday night conference call with California health officials, they launched a gumshoe-style investigation. Although they now knew what the virus looked like, its origins remained a mystery.

With guidance from the CDC, state health investigators visited the children, their families, and their schools and friends. They took blood samples and interviewed more than 90 people.

"We were thinking there had to be some contact with pigs," said state epidemiologist Gil Chavez. They came close; the boy had visited the zoo; the little girl had been to a county fair. But no luck.

"We absolutely couldn't establish any links with swine whatsoever," Chavez said. Furthermore, the children lived 120 miles apart and had never met.

On Monday, April 20, Veratect, a private firm based in Kirkland, Wash., that conducts disease surveillance, contacted the CDC, concerned about the respiratory illness in Mexico. But in an e-mail, medical director James Wilson acknowledged, "I suspect this is probably a false alarm."

North of the border, Canada also was picking up nervous chatter. After its devastating experience with severe acute respiratory syndrome, or SARS, in 2003, Canada's public health apparatus is highly attuned to potential outbreaks. Through the international laboratory grapevine, U.S. public health workers heard that Mexico was shipping samples to Canada.

But it wasn't adding up, Jernigan said. The situation in California -- children with mild cases of swine flu who had fully recovered -- didn't match the dire picture in Mexico.

By the time Richard E. Besser, acting director of the CDC, convened the weekly pandemic flu meeting at 8:30 a.m. on April 22, CDC lab technicians had confirmed that the viruses that infected two teenagers in Texas identically matched the California bugs.

"The first case of swine flu, you think: No big deal," Besser said in an interview. "The second is a little less common. But then when the Texas cases came in, the epidemiologist in me knew the probability of those being unrelated events has gone way down."

From a polished wood conference table next to the CDC's 24-hour Emergency Operations Center, Besser said the agency would step up its pandemic preparations, increasing the center's staffing from 10 to 70.

The next day, the CDC convened a teleconference with the 50 state public health labs in the United States and urged extra vigilance.

By evening, as the rain began to fall, Cox's team was completing its analysis of the specimens from Mexico. The genes were identical to the H1N1 swine variation found in California and Texas. Finally, she recalled, "we were really putting together a couple of major pieces of the puzzle."

One mystery had been solved. But for Cox, whose house would be torn down to the studs, the marathon was just beginning. 

... and history from yet another perspective...

Canada's 'flu hunters' track a wily new virus
ANDRÉ PICARD
From Tuesday's Globe and Mail
May 5, 2009 at 4:13 AM EDT
http://www.theglobeandmail.com/serv...y/National/home


Canada's response to the potential swine flu pandemic of 2009 began, fittingly enough, with the late-night buzz of a BlackBerry.

Frank Plummer, scientific director of the National Microbiology Laboratory, was relaxing in his Winnipeg home, half-watching a hockey game, when an e-mail arrived from Celia Alpuche Aranda, head of the Mexican national microbiology lab. She was concerned about an ever-worsening outbreak of atypical pneumonia that scientists there were unable to identify.

Earlier that day - Friday, April 17 - the U.S. Centers for Disease Control and Prevention had alerted the World Health Organization to a seemingly unconnected occurrence: two unrelated children diagnosed with swine flu in California.

Dr. Aranda packed up samples from 51 seriously ill people in Mexico and shipped them to Winnipeg. She sent a similar package to the CDC in Atlanta.

Meanwhile, the flu hunters - the nickname given the epidemiologists and laboratory scientists who obsessively track the permutations of wily influenza viruses - were already at work.

While they usually toil invisibly, doing everything from mucking about farms in China wringing the necks of ducks to pulling all-nighters with genetic sequencers, their most powerful tool remains the gathering of information, pieced together like a puzzle.

Epidemiological information-gathering has become much easier with instant communication tools like e-mail. But cyberspace also poses the greatest challenge, because information - and fear - spreads a lot more quickly than a virus ever could, even one with pandemic potential.

Before Dr. Aranda's samples arrived in Winnipeg, the blogosphere was aflame.

On April 21, ProMed-mail, the blog of choice for flu hunters, posted a long item about swine influenza A H1N1, the virus identified in the California children, ominously noting the "possibility that human transmission of this new influenza virus has occurred."

Public health officials were also watching, with increased concern, an outbreak of flu in Mexico, a favourite vacation destination of Canadians. The Global Public Health Intelligence Network, an initiative of the Public Health Agency of Canada, sent out its first dispatch about an acute respiratory syndrome in Veracruz, Mexico, on April 10 and within days it was abuzz.

While there was no increase in flu activity in Canada, both the Ontario Agency for Health Protection and Promotion and the B.C. Centre for Disease Control sent alerts to public health units on April 21 telling them to watch for respiratory symptoms in Canadian travellers returning from Mexico.

Journalistic antennae went up too. Helen Branswell, the medical reporter at The Canadian Press, posted one of the first stories. "U.S. public health authorities are investigating two cases of swine flu in unrelated children in California, a development that has officials in Canada and elsewhere on alert," she wrote presciently.

On April 22, the CDC announced three more swine flu cases in the United States, and the Canadian Public Health Agency began investigating reports of Canadians returning from Mexico with a strange respiratory ailment. The initial fear was that SARS had returned.

But on the morning of April 23, Dr. Plummer, whose team had worked around the clock to analyze the samples it had received the day before, held a conference call with top Mexican health officials to reveal his findings: 17 of the 51 samples contained a completely new type of virus, one that had originated in pigs - swine influenza A H1N1.

In Canada, provincial health officials sent out a far more detailed alert, this time to physicians, about travellers returning from Mexico.

The arrival of a new flu virus, one that had eerie similarities to the killer Spanish flu of 90 years ago, told David Butler-Jones, Canada's Chief Public Health Officer, that it was time to activate the Canadian Pandemic Influenza Plan.

The World Health Organization also kicked it up a notch. A mere 22 minutes after receiving the results of the Canadian testing, the WHO opened its emergency operations centre. It also made the first explicit connection between the "influenza-like illness in the U.S. and Mexico" and convened a panel of international experts to determine the threat that swine influenza A H1N1 posed.

The pandemic alert level was already set at three on the six-rung ladder (representing none or very limited human-to-human transmission) because of the ever-present risk posed by avian influenza A H5N1, which continues to flare up sporadically around the world. That scale, which is a barometer of future risk of a pandemic (it does not reflect current severity), soon jumped to level four, then five.

Travellers carried the swine flu from Mexico to the far reaches of the world - by last Sunday, cases had been reported in 17 countries on five continents - but fear travelled far more quickly and widely.

While the news moved through cyberspace on a 24/7 news cycle, the public was able to follow the steady spread and rise in swine flu numbers. The genome of the influenza A H1N1 virus was decoded in record time, revealing that it consists of a strange hybrid of North American swine influenza, North American avian influenza, human influenza and swine influenza typically found in Asia and Europe.

One of the first things scientists at the CDC in Atlanta and the NML in Winnipeg did was start growing seed stock from the virus, the fundamental element needed for a vaccine. Production of the vaccine could begin in mid-May; a final product could be on the market within four months, and about two billion doses produced within a year.

While not many of the swine-flu hunters are getting their hands dirty on hog farms, there is no shortage of grunt work.

A group of North American scientists - including four lab workers from the National Microbiology Laboratory - essentially built a new lab from scratch in Mexico City so they no longer have to send samples to Canada and the United States for testing. It was up and running on April 26. That has greatly speeded up testing, but has also given the impression that the virus continues to spread quickly in Mexico, which is not necessarily the case.

The laboratory work is also providing important clues on the epidemiology of the disease. It revealed that the first case of influenza A H1N1 occurred in Mexico on March 17, and the first case in the United States on March 28. The first death from swine flu was a 39-year-old woman who died on April 12 in Oaxaca, a popular tourist area. On that same day, a farm worker who had just returned from holidays in Mexico is believed to have infected pigs on a farm in Alberta.

This data is a comfort to flu hunters because it reveals that the virus has actually been circulating for about six weeks, meaning that many more people in Mexico (as well as travellers to the country) have been exposed to the virus than previously believed, without falling ill.

In coming days, information will be published on the fatality rate and severity of the flu to date, which will provide hard data for modelers and risk assessors to better determine where the pandemic may or may not be going.

Still, in our impatient world, there is not always a willingness to give the flu hunters the time to do their painstaking work. Nor is there, in the BlackBerry age, a recognition that influenza, an ancient disease, moves at its own pace, more often than not slowly and relentlessly. 

http://www.npr.org/templates/story/...oryId=103858702

Health & Science
Inside The New Flu Virus
by Richard Knox

Morning Edition, May 7, 2009 · A crash effort to analyze the genes of the swine flu virus has revealed that it first emerged in humans last year — most likely last fall.

"The consistent range we're getting out is the second half of last year — between June and December," says Oliver Pybus of Oxford University. "The best estimate is the middle of that range, kind of September."

That means the newly recognized virus has been hiding in plain sight for the past eight months or so. Researchers say it probably had been circulating in Mexico and causing disease there, but its presence was masked by cases of regular flu and the absence of lab tests to identify the newcomer.

A Dizzyingly Complex Virus

Genetic analysis of the swine flu virus is proceeding at a furious pace, abetted by the Internet. The research is not only yielding early insights about the virus's lineage and age, but scientists say the work will also be crucial in tracking how the virus is evolving and what sort of threat it may represent over the coming months.

Pybus is one of 11 scientists around the world who've been digging through genetic data on thousands of animal and human flu viruses and sharing it with each other on a new swine flu wiki. This is the fastest a new flu virus has ever been identified and placed on a family tree that's dizzyingly complex.

"This has got to be the way this happens from this point forward," says Michael Worobey of the University of Arizona, another member of the spontaneous new collaboration, which includes groups from Hong Kong to Edinburgh and Tucson, Ariz., to Gainesville, Fla.

Where Did The Virus Come From?

The effort has already shed considerable light on where the new-found virus came from and over what period it evolved. Its great-grand-daddy was what flu scientists call a "triple reassortant" — a three-fer virus made up of genes from a seasonal human flu virus of the H3N2 family, a North American bird virus and a classic swine virus.

The three separate viruses got together in a pig somewhere. When all three ancestor viruses infected the same pig cell, that enabled them to swap genes, a trick flu viruses specialize in.

"Pigs are special because they are easily infected with swine viruses, avian viruses and human viruses," says Joan Nichols of the University of Texas in Galveston. "That makes pigs a mixing pot." The pot keeps boiling, genetically speaking, because flu viruses are notoriously mistake-prone as they replicate within a bird or mammalian "host."

"This virus doesn't have a proof-reading mechanism, so it makes a lot of sloppy little mistakes along the way," Nichols says. Some viruses with those "mistakes" survive and thrive because the mutations allow them to spread more efficiently or infect another species. Other mutations cause more severe disease in the virus's hosts.

A Flu Stew

Scientists say the swap meet that gave rise to the newly discovered swine flu virus happened 10 or 20 years ago. That "triple reassortant" spread among swine for years, but it wasn't yet able to spread among people. It acquired that ability only last year, when the old "triple reassortant" combined again with two other pig viruses that circulated in North American and Eurasian swine.

That created the virus that's currently bedeviling the world. The new collaborative group calls it A/California/04/2009 because it was first identified near San Diego in April 2009. It is, in fact, mostly a swine virus with human and bird elements.

Pybus says it really should be called the "gallimaufry" virus. That's a 16th century French word that means "stew" or "hodgepodge."

Finding Clues For Next Flu Season

Scientists will track genetic changes and correlate them with the kinds of disease it causes in the Southern Hemisphere, where the flu season begins this month. So far the swine flu virus has begun to turn up in Costa Rica, Colombia, El Salvador and Guatemala.

"We're going to be actively monitoring what it does as it moves through the population," says Joan Nichols. "As it turns around and comes back to us in the fall, we'll know much more about it."

If it starts causing severe and fatal disease at a high rate in the Southern Hemisphere, that will be obvious enough. Scientists will quickly analyze viruses from such cases to see if they can identify the genetic changes that correlate with increase virulence.

But unfortunately, the absence of such an obvious signal this summer may not mean the virus won't evolve into a pandemic killer in the fall. That's because researchers know relatively little about the genes that confer virulence.

Jeffrey Taubenberger of the National Institute of Allergy and Infectious Diseases knows as much about virulence in flu viruses as anyone. He led an effort to reconstruct the killer virus of 1918, which has enabled scientists to probe what made it so dangerous.

Taubenberger says virulence doesn't appear to reside in a particular gene mutation. Instead it comes from the interaction of still-unknown genetic elements, which he calls "a constellation effect."

"Virulence and other behaviors are totally dependent on the overall makeup of the virus," Taubenberger says.

Nichols says the only solution is to watch the newly discovered virus obsessively in the coming months. "Remember," she says, "this virus hasn't stopped. It's just begun." 

Taubenberger's (et al) work (which is Noble Prize caliber work, in my opinion) firmly established that the 1918 H1N1 was a pristine avian virus; this virus did not pass through an intermediary host, before it began to inhabit human hosts. So, it would necessarily follow, from what he articulates with regard to a "constellation" of factors, that the factors that combine to ensure an extreme level of virulence were not present in the original iteration of the virus; this suggests that they were "acquired" through a mutational process of some sort, or through another combinatorial method, such as that already achieved by the current swine H1N1 variant. Something materialized in the course of its travels that resulted in the 1918 H1N1 going utterly berserk. That strain that was completely recapitulated by Taubenberger was the berserker; as far as I know, there is no extant copy of the original virus, anywhere.

An experiment was done in Britain (I believe that it was in 1930) that involved the H1N1 strain that was, by that time, the common seasonal strain; this virus was passed through a succession of experimental animal hosts (I believe it was successive generations of ferrets and mice) until a level of virulence was arrived at, in mice, that would have more or less duplicated that of Taubenberger's specimen. I can't recall the name of the primary researcher, at this point, but I'll look around later today and see if I can find it. It was a very interesting experiment. 

In 11 days (April 26 - May 7) we have gone from 20 confirmed cases to 896.
There are more probable cases than confirmed.
Even though there have been only 2 deaths and 35+ hospitalized, healthcare is readily available for now.
But going from 11 to 896 cases in 11 days is a factor of 44.8! and we know it in actuallity is much larger.
In slightly over a month from now, the healthcare system will be unable to handle the cases.
Remember the typical seasonal flu is spread out over a 5 month period.
This (at the current rate of confirmed only) will exceed the normal flu season in less than 1.5 months. 

That increase in the number of cases is very misleading. Prior to 2 weeks (?) ago they werent even looking for it, and when they did start, I believe there was only the CDC lab in Atlanta who could confirm cases. Increases of case numbers is more likely a reflection of the increase in testing locations, and getting caught up with the backlog of tests and is misleading.

There is also a strong likihood that the virus has been in the US for much longer than 2 weeks.

Of course there will be more cases to come. Probably lots more. Perhaps up to 1/3 the entire population if this pandemic is as widespread as some past ones. But all indications thus far suggest they also will be mild cases, or we can hope.

I doubt the healthcare system will be overwhelmed if the cases continue to be mild. There are thus far only about 35 hospitilized cases in the entire US out of likely thousands of cases. That is less than one/state. And when most of these people recover, they will go home to make room for other severe cases.

This of course could go any way, but I think it's a bit premature from what we've seen thus far to conclude that the healthcare system will be overwhelmed in a month from now. 

__________________
.

Living well is the best revenge. 

[QUOTE=Mosaic]That increase in the number of cases is very misleading. Prior to 2 weeks (?) ago they werent even looking for it, and when they did start, I believe there was only the CDC lab in Atlanta who could confirm cases. Increases of case numbers is more likely a reflection of the increase in testing locations, and getting caught up with the backlog of tests and is misleading.QUOTE]

At 20 cases on April 26 there was no backlog.
There is a backlog now, so the actual cases are at a minimum of 896 now.
My numbers are minimum. I am not overstating. I am understating.
Volume in a short period can overload the healthcare system.
Picture the ER waiting rooms.
Picture sick healthcare workers.
Picture no available ICU rooms or ventilators.
The numbers are what the numbers are.
Have you put pencil to paper and looked at the calculations? 

Statistics are like bikinis. They show a lot, but hide the essentials.

I'm sure there always have been more cases than the official numbers indicate. Just like the numbers out of Mexico, the CDC numbers have been questionable from the beginning for any number of reasons. They are not a good reflection of what swine flu is doing in the US. In my opinion, making predictions based on inaccurate numbers also can lead to inaccurate conclusions.

From watching the past couple weeks, even with a great increase in cases, if the virus does not change (it could), most future cases likely also will be relatively mild, treated at home, and wont overwhelm the system. I hope that is correct. We'll know a month from now. 

__________________
.

Living well is the best revenge. 

IMHO, as Mosaic says, even with the first 20 Confirmations on April 26 the CDC case numbers were grossly understated... not due to a CDC backlog, but due to a shortage of collected samples to test.

I don't think any of the experts believe that Swine Flu arrived in the US on April 26. I'm guessing it was seeded in parts of the country at least a month prior to that.

What else would explain the facts that, for example, only 10% of the current cases had a travel history to Mexico and few of the ~45 cases in the Seattle area have any apparent connection to each other. Both of these things indicate a virus that is endemic in at least parts of the country, and IMHO that didn't happen in just the past couple weeks.

But I could be wrong.


MomCares 

The first "sticky" is tracking the day-to-day cases.

Why?

Is it to see the trend and magnitude, and try to determine the threat level?

Make a chart with the left verticle scale starting at 20 cases and double for each unit up the scale. I.E. 20, 40, 80, 160 etc.
do the horizontal scale as dates.
Track the trend and rate of change.
The trend is valid until it changes.

The CDC confirmed data is just that, "Data"
It's not perfect data, but it's what we have.
If you're not going to use it for anything, why post it?

Again I ask, "What's the purpose of tracking the cases?" 

We've had numerous discussions about this, and I think it's somewhat useful for tracking the trend (at this point primarily only for tracking the spread into newer countries), but NOT the magnitude.

As we've said before, we track those numbers because they're all we have (and it keeps us off the streets), but we understand they're wrong (as indicated by numerous notes on the lists).

I think NYC Mayor Bloomberg nailed it when he said "You want 200 more cases? Test 200 more people."

Lately when I update the US numbers the phrase "It's everywhere... it's everywhere" runs through my head.


MomCares 

People interpret data all the time. But not everyone will use or interpret the same data in the same way, especially when the basic data may be flawed.

If one reaches a conclusion or makes a prediction based on such data, there is no reason to assume everyone else will agree with it.

You (y2kmisfit) made a prediction, I disagree with it and stated why. And you stand by what you have said. Nothing wrong with that. We each have an opinion. Who doesnt with pandemic flu?

That is why we are here - to discuss such things.  

__________________
.

Living well is the best revenge. 

Btw... Helen Branswell just posted an interesting article on this topic...

http://www.curevents.com/vb/showthr...4534#post944534 

Swine Flu Outbreak From Mexico to New Zealand: Timeline
By Simeon Bennett and Kanoko Matsuyama
http://www.bloomberg.com/apps/news?...TBnY&refer=home


May 11 (Bloomberg) -- The following is a timeline of the outbreak of swine flu, a virus that normally infects pigs and causes seasonal flu-like symptoms such as fever and coughing.

The virus has been detected in people in Argentina, Australia, Austria, Brazil, Canada, China (Hong Kong), Costa Rica, Colombia, Denmark, El Salvador, France, Germany, Guatemala, Ireland, Israel, Italy, Japan, Mexico, Norway, the Netherlands, New Zealand, Panama, Poland, Portugal, South Korea, Spain, Sweden, Switzerland, the U.K. and the U.S.

The spread of the pathogen, formally known as H1N1, has prompted health officials worldwide to screen travelers and stockpile medicines such as Roche Holding AG’s Tamiflu.

May 10: Swine flu killed a man in Washington state, the third U.S. death from the virus. American scientists said the pathogen lacks the lethal genetic traits of the virus responsible for the 1918 pandemic or the H5N1 bird flu virus that’s killed more than half of those infected. Norway reported its first case as the World Health Organization said 4,379 cases were confirmed in 29 nations, not including Norway.

May 9: Costa Rica became the fourth nation to report a swine flu-related death, as Japan and Australia confirmed their first cases, all in people who had traveled to Canada or the U.S. The WHO said the virus spread to 3,440 people in 29 countries worldwide. Mexico confirmed 48 deaths among 1,626 cases, as confirmed cases in the U.S. rose to 1,639, with two deaths.

May 8: Canada reported its first death linked to swine flu in a 30-year-old woman with “pre-existing medical conditions.” Hong Kong released 351 people after a week-long quarantine, including 286 from the downtown Metropark Hotel. The WHO said 2,500 infections had been confirmed worldwide, as Panama reported its first case and nine other nations added new cases. Brazil reported its first case of human-to-human transmission. Health ministers from the Association of Southeast Asian Nations said the WHO should review its criteria for declaring influenza pandemics to include the severity of illness a virus causes as well as its transmissibility. China said it aims to stockpile antivirals for 1 percent of its population.

May 7: The WHO said swine flu may affect at least one-third of the world’s 6 billion people within the next year. Israel confirmed the country’s sixth case and South Korea confirmed its third. Brazil confirmed four cases and Argentina one, both their first cases. Spain’s cases rose to 88 from 81. Total swine-flu cases in the U.S. reached 896, with the number in Illinois growing to 204. Mexico confirmed 1,204 cases including 44 deaths. The Netherlands reported its second case. Hong Kong released 34 people, mostly passengers on the same flight from Mexico as an infected man, after seven days of quarantine.

May 6: Guatemala, Poland and Sweden confirmed their first cases, bringing the number of countries infected to 24. Mexico confirmed 42 deaths and 1,112 swine flu illnesses. The number of confirmed cases in the U.S. jumped to 642; Illinois had the most cases with 122, followed by New York with 97. The U.K. reported a total of 32 cases with an additional four cases associated with travel to Mexico. Brazil reported 26 suspected cases. Indonesia reported its first suspected case.

May 5: Swine flu killed its first U.S. resident, a 33-year- old school teacher from Texas, and new infections in Europe brought the WHO to the verge of declaring a pandemic. Mexico raised its death toll to 29 from 26, and said the outbreak may cut gross domestic product by 0.3 percent to 0.5 percent this year. Canada confirmed 140 infections, up from 101, including its first “severe” case. South Korea, New Zealand and Italy added new cases, though no nations were added to the list of those where the virus has been detected. Health authorities in the U.S. said schools shouldn’t close unless so many students or teachers get sick that the institutions can’t function, reversing earlier advice.

May 4: The WHO said swine flu spread to more than 1,000 people in 21 nations worldwide, as El Salvador and Portugal confirmed their first cases. Mexico raised its death toll to 26, even as it lowered its health alert one level to orange from red and Health Minister Jose Cordova said the nation will start reopening government offices, businesses, universities and schools from May 6. The nation also sent a plane to China to pick up citizens who had been quarantined there because of swine flu concerns.

May 3: Mexico raised its death toll to 22 and said 590 people have been infected. Cordova said the nation’s outbreak had peaked and was in decline. In the U.S., the virus spread to 226 people in 30 states. Colombia, Ireland and Italy confirmed their first cases and South Korea added a second “probable” case.

May 2: South Korea confirmed its first cases, bringing the number of countries with definite infections to 15. Six other nations reported more cases to the WHO, including among people who hadn’t traveled to Mexico. Canada reported the world’s first case of the virus jumping to pigs from a human, probably after a farm worker in Alberta province became ill during a trip to Mexico. Mexico said citizens had been quarantined in “unacceptable conditions” in China without having shown flu symptoms. China said the measures were necessary.

May 1: Hong Kong confirmed its first case, prompting the government to declare a public health emergency and cordon off the hotel where he was staying. France and Denmark also confirmed their first cases. Japan and South Korea both found suspected cases.

April 30: California had 16 confirmed cases and 41 suspects. New Jersey confirmed five cases. One case confirmed in Washington D.C. A possible case was found each at New York’s Pace University and Harvard School of Dental Medicine. Spain confirmed 13 people had swine flu. The U.K. confirmed three more cases, making a total of eight. The Netherlands found the first case. Brazil reported 4 suspected cases. Israel tested two more suspected cases. An infected man possibly passed the flu to two people in Germany. Two suspected cases proved negative in South Africa. France found a possible case. Japan found a suspected case that was later found to be negative.

April 29: The World Health Organization raised its six-tier alert to five, the second-highest rating, and said the first influenza pandemic since 1968 is imminent. President Barack Obama said the world faces a “very serious situation.” Cases in the U.S. reached 91, including the nation’s first death, a toddler in a Houston hospital. California confirmed 14 cases and a further 29 probable cases. New York State confirmed 51 cases, including 49 in New York City. Two cases were confirmed in Massachusetts, with three in Maine. Texas had 16 cases, with one each in Nevada, Indiana and Arizona, and two cases in Michigan. The University of Delaware reported four suspected cases. Mexico reported eight confirmed deaths, with 99 confirmed cases. Canada confirmed three additional cases in Ontario. Peru confirmed the nation’s first case. Costa Rica found a second case. A total of 10 people in Spain tested positive. Switzerland had 21 suspected cases. The U.K. reported three additional confirmed cases, bringing its total to five. Germany confirmed two cases. Two suspected cases were reported by South Africa. Austria confirmed that country’s first case. New Zealand confirmed 14 cases. Australia was testing 112 people. Two suspected cases were found in Brazil. Malaysia said one case is under observation. Singapore referred 17 people for medical assessment, finding four negative.

April 28: The confirmed cases of swine flu in the U.S. jumped to 64 and New York City had 45 cases confirmed. Indiana reported a case in addition to the 64 total cases in four other states and New York City. Two probably cases were reported by South Carolina. Canada confirmed 7 new cases, making a total of 13. Nine people were suspected cases in Switzerland. Poland was checking 2 suspected cases. Spain confirmed a second case. Germany reported 3 suspected cases. One case was confirmed in Israel. One case was found in Costa Rica. Five cases in Austria were found to be suspected. The U.K. was testing 9 cases in contact with 2 confirmed people. Initial test result of a case in Thailand was found negative. New Zealand confirmed 11 people had swine flu, the first cases in the Asia-Pacific region. One suspected case was found in South Korea, possibly the nation’s first case. Thailand said one is under observation for possible swine flu.

April 27: New Zealand said 10 students confirmed to have Type-A influenza are “highly likely” to have swine flu. A further three students were being tested. Australia said it’s examining five potential cases. Spain confirmed Europe’s first case of swine flu and said it’s testing an additional 16 people for the virus. A second Israeli is suspected of having swine flu. The confirmed cases grow to 40 in the U.S., including 28 in New York. New York also said at least 100 additional people may have been infected. Flu-related deaths reached as many as 149 in Mexico. The U.K. confirmed two people contracted the disease. Five people in the Australian state of New South Wales will be tested for swine flu.

April 26: Eight cases are reported in New York City and one in Ohio. Four cases were reported in Nova Scotia and two in British Columbia, Canada. Mexico said its flu outbreak has killed 103 people, of whom 20 are confirmed to have died from swine flu. One Israeli is hospitalized with suspected swine flu.

April 25: Two cases are reported in Kansas; one is reported in California.

April 24: Mexico said 20 people died from swine flu, another 48 deaths may have been caused by the virus and more than 1,000 people became sick with flu-like symptoms. One case is reported in San Diego County.

April 23: Two cases are reported in San Diego County, one in Imperial County, California, and two in Guadalupe County, Texas.

April 21: Two cases are reported in San Diego County, California. 

Swine Flu Origin > Fort Leonard Wood (FLW), Missouri

- snip -

Starting in January of 2009 Fort Leonard Wood (FLW) in central Missouri experienced a dramatic increase of pneumonia cases among soldiers stationed at the base.

The rate of pneumonia in February hit 658 / 100,000 p-yrs base wide and over 3,500 / 100,000 p-yrs within two isolated barracks which housed soldiers from the A and H companies, 554th Engineer Battalion.

Base wide the rate was double the 2 year base line average and 10 times the baseline within the A and H companies.[1]

read article:

http://www.opencube.com/h1n1/origin_missouri.htm


credits pflu 

No , can´t be true :

http://www.cdc.gov/mmwr/preview/mmw...mm58d0421a1.htm 

From a Canadian perspective...

How the swine flu outbreak is unfolding: a timeline
Last Updated: Thursday, June 4, 2009 | 6:10 PM ET
CBC News
http://www.cbc.ca/health/story/2009...u-timeline.html


June 4

The number of reported cases of swine flu in Ontario jumps 25 per cent in the first few days of June, with most of the new cases in the Greater Toronto Area.

Two residents of the remote Manitoba community of St. Theresa Point First Nation are diagnosed with swine flu.

June 3

Two Winnipeg paramedics who transported northern Manitoba patients suspected of having swine flu might have contracted the disease from them.

June 2

Keiji Fukuda, acting assistant director general of the World Health Organization, says the spread of swine flu in Australia, Europe and Asia has nudged WHO closer to considering declaring a pandemic.

A 60-year-old Toronto man dies after contracting swine flu. He is the third Canadian believed to have had swine flu at the time of his death, though medical officials are unsure of how large a role the H1N1 virus played.

June 1

More swine flu cases are reported in the Canadian North, with people in Nunavut and the Northwest Territories diagnosed with the disease.

May 22

Research published in the journal Science suggests that genes in the new H1N1 strain have been circulating undetected in the animals for at least 10 years. Rebecca Garten of the U.S. Centers for Disease Control and Prevention and her colleagues said pig populations need to be closely monitored for emerging influenza.

May 21

Mexico City lowers its swine flu alert level from yellow to green after no new infections are reported for a week.

May 19

The World Health Organization says it will take longer than expected to produce a vaccine for the swine flu virus. Flu experts are having a tougher time than expected growing the virus in the lab making it difficult for scientists to retrieve a seed stock necessary to make the vaccine. The organization says drug manufacturers won't be able to start making a vaccine until mid-July at the earliest.

May 18

Canada lifts a travel advisory for Mexico, as cases of swine flu wane. Canada's chief medical officer of health — Dr. David Butler-Jones — says it appears "we're over the worst of it in Canada for this season."

May 11

China reports its first confirmed case of swine flu — a student who had returned from the United States. Health officials searched for about 150 people who shared the same flight with the student, who is reported to be suffering from mild flu symptoms.

The World Health Organization says there are no signs of community transmission of the virus outside of North America.

A Windsor, N.S., clinic closes after being set up to test for swine flu following an outbreak at a local school.

May 8

An electron microscope image shows a swine flu virus culture obtained from a California patient, in an image obtained from the U.S. Centers for Disease Control (CDC) in Atlanta. Health officials in Alberta say swine flu played a role in the death of a woman in northern Alberta on April 28. They note that the woman — who was in her 30s — had chronic pre-existing medical conditions, and it is still not clear to what extent swine flu was a factor in her death. The cause of death was initially linked to her pre-existing medical conditions.

On May 5, health officials confirmed that another member of the woman's family had contracted a mild form of swine flu. After that confirmation, officials ordered further testing on the dead woman. Those tests showed that she also had a mild form of the virus.

The other family member is recovering at home.

May 7

The World Health Organization repeats a previous declaration that pork is safe to eat. The health body stresses that existing sanitary and animal health checks are sufficient to safeguard the food supply against the swine flu virus. As many as 20 countries had restricted pork imports from countries that had recorded swine flu cases.

May 6

The World Health Organization says it will convene a meeting of experts on May 14 to consider whether vaccine manufacturers should shift from seasonal to pandemic flu production, in response to the swine flu outbreak. At least 20 companies make flu vaccines.

Researchers at the National Microbiology Laboratory in Winnipeg say the swine flu that's spreading in Mexico and Canada is the same strain. The researchers rule out a mutation to explain why the strain has killed 42 people in Mexico while all cases in Canadian except for one have been relatively mild.

China lifts a quarantine order on 25 students and a professor from the University of Montreal. The group — which was in China to learn Chinese — were placed in a lakeside hotel after being pulled aside by officials in Changchun after their plane landed in the northeastern city five days earlier.

May 4

The number of cases worldwide surpasses 1,000 in 20 countries. In Edmonton, a young girl comes down with serious enough symptoms that she is treated in hospital. Health officials say she is responding well.

World Health Organization director general Margaret Chan tells the UN General Assembly there is "no indication" that the outbreak is similar to a pandemic in 1918 that killed tens of millions of people around the world.

May 3

China quarantines 70 Mexicans and 25 Canadian students amid concerns of swine flu. It also bans imports of pork from Alberta, after the virus is found on a central Alberta pig farm.

May 1

The World Health Organization says efforts are being stepped up to develop a vaccine against the current swine flu virus. Dr. Marie-Paule Kieny, WHO director of the Initiative for Vaccine Research, tells reporters that the U.S. Centers for Disease Control and Prevention is working to produce a "seed stock" to form the basis for a swine flu vaccine. That step is expected to be completed within four weeks and samples would be sent to vaccine manufacturers immediately.

The number of confirmed cases in Canada rises to 51, including New Brunswick's first case — a woman, in her 20s who recently returned from Mexico. She did not require hospital treatment.

April 30

The World Health Organization WHO begins distributing a stockpile of antiviral drugs to a number of countries, including Mexico, as confirmed human cases of swine flu rise to 236 worldwide.

The number of confirmed cases of swine flu in Canada rises to 34 as 15 new mild cases are identified: five in B.C., four at King's-Edgehill School in Windsor, N.S., four in Calgary, one in Montreal and one in Toronto.

The number of countries reporting cases rises to 12 as the Netherlands, Switzerland and Peru report their first cases. The WHO recommends that all countries track any suspect cases and ensure medical workers dealing with them wear protective masks and gloves. But it stops short of recommending travel restrictions, border closures or any limitation on the movement of people, goods or services.

The organization also says it will stop referring to the illness as "swine flu." It will use the technical scientific name "H1N1 influenza A." A spokesman says it wants to make it clear that there's no danger posed to people by pigs.

April 29

The World Health Organization raises the pandemic alert level to phase five, which is characterized by human-to-human spread of the virus into at least two countries in one region. The move is a strong signal that a pandemic is imminent and that countries should make sure they are ready to cope with it.

"All countries should immediately activate their pandemic plans," WHO director-general Dr. Margaret Chan told a news briefing.

In Canada, health officials confirmed three new cases in the Toronto area and three more in B.C. bringing number of total Canadian cases to 19.

In the United States, the Centers for Disease Control and Prevention confirms the first swine flu death outside Mexico.

A 23-month-old child died of the illness in Texas. The toddler had traveled from Mexico to Brownsville with his family to visit relatives earlier in the month. When he showed symptoms of the flu he was taken to Houston for treatment.

The CDC points out that the death is one of 53 seasonal flu-related deaths of children in the United States during the current flu season.

April 28

Alberta confirms two mild cases — one in Calgary, the other in northern Alberta. Ontario confirms four cases. The number of confirmed cases in Canada hits 13 — all are mild.

British tourists line up to check in at the airport in Cancun, Mexico. Several holiday tour operators suspended trips to Mexico for at least a week in response to the flu outbreak. Ontario health officials say anyone who shows up at a hospital with respiratory symptoms will be required to wear a mask.

Several tour companies announce they are suspending travel to Mexico.

Cuba suspends flights to and from Mexico for 48 hours.

Ecuador bans the import of pigs and pork from Mexico and the U.S.

Restaurants in Mexico City are ordered to serve take-out food only. Gyms, sports clubs, swimming pools and pool halls are ordered closed.

California Gov. Arnold Schwarzenegger declares a state of emergency, a move that gives his administration easier access to more money.

The World Health Organization says the number of confirmed cases has hit 79. The organization also says the swine flu outbreak could be a mild pandemic. But it cautions that the 1918 Spanish flu pandemic started out mild but wound up killing more than 20 million people.

April 27

King's-Edgehill School headmaster Joseph Seagram, right, chats with headgirl Ashley Snow, and headboy Omer Mullick at the Hants Community Hospital in Windsor, N.S. Four students from the school have had mild cases of swine flu after visiting the Yucatan Peninsula. The World Health Organization upgrades its pandemic alert level to four, indicating that a pandemic is possible, but not a foregone conclusion. It's the first time the organization has upped its pandemic meter.

The Public Health Agency of Canada issues a travel advisory, recommending that Canadians postpone non-essential travel to Mexico.

The federal government says it will monitor but not bar Mexican migrant farm workers coming to Canada to work on local farms.

Canada's chief medical officer of health, Dr. David Butler-Jones, says Canada will likely see severe cases of swine flu and "we will likely, unfortunately, see some deaths as well. We hope not, but it is a normal part of an influenza outbreak."

April 26

Soccer players leave the field at halftime in an empty stadium in Mexico City. Authorities closed the stadium to the public in response to the swine flu outbreak. Nova Scotia health officials confirm four cases of swine flu. B.C. officials confirm two cases. In the U.S., the Centers for Disease Control confirms 20 cases.

As well, health officials in the U.K., Spain, Israel, Australia, New Zealand and Brazil say they are investigating suspected cases of swine flu.

None of the cases outside Mexico is reported as serious.

April 25

A committee convened by the World Health Organization to assess the flu outbreak declares a public health emergency of international concern.

April 24

Health Minister Leona Aglukkaq speaks to the media about the outbreak of swine flu. Further Public Health Agency of Canada results confirm that the outbreak in Mexico is swine flu.

Health Minister Leona Aglukkaq and Canada's chief medical officer Dr. David Butler-Jones hold their first news conference.

Officials close schools, museums and libraries in Mexico City in an attempt to limit the spread of the virus.

The Centers for Disease Control says the two California cases are linked to the flu outbreak in Mexico — even though neither of the children had been to the affected area.

April 23

Preliminary tests show signs of swine flu in the Mexican samples. The Centers for Disease Control and Prevention in the United States holds its first media briefing on swine flu.

April 22

The Public Health Agency of Canada receives the Mexican samples.

April 21

The Centers for Disease Control publicly reports two cases of swine flu in California.

April 17

Wearing protective face masks a woman holding her child waits at the emergency area where people with swine flu-like symptoms are checked at the Naval hospital in Mexico City. The Mexican government asks Canada's National Microbiology Lab in Winnipeg for help in testing samples from sick people.

The California girl's sample arrives at the Centers for Disease Control and is tested. It shows swine flu. The CDC is now dealing with two unrelated cases of a new flu strain never before seen in people.

April 14

The California boy's sample arrives at the Centers for Disease Control. Tests show he had swine flu. The boy had not been in contact with pigs.

April 6

Pigs are seen on a farm run by Granjas Carroll de Mexico on the outskirts of Xicaltepec in Mexico's Veracruz state. Mexico's Agriculture Department said its inspectors found no sign of swine flu among the pigs and that no infected pigs have been found anywhere in Mexico. A Kirkland, Wash., company — Veratect — notices a sudden uptick in respiratory disease and concerns at clinics in the Veracruz area and changes in patterns of behaviour in the local populace.

The company sends out an alert to its clients, including the World Health Organization and the U.S. Centers for Disease Control.

Local health officials declare a health alert in the town of La Gloria in Veracruz state. More than a thousand people in the town of 3,000 had sought medical treatment for a flu-like illness in the previous week.

March 30

A little boy in San Diego County is taken to a clinic complaining of a fever, vomiting and a cough. The doctor was working on a special disease surveillance program. He sent the boy's sample off for testing.

March 28

A little girl is taken to a clinic in California for treatment of flu-like symptoms. The clinic happened to be involved in a flu study, so instead of just treating her and sending her home, they send a sample off for testing.

March 18

The Mexican government starts tracking an increase in cases of a flu-like respiratory illness in the state of Veracruz.