North America: H1N1 Influenza, Human

[Reasonable Rascal]

INFLUENZA A (H1N1) VIRUS, SWINE, HUMAN - NORTH AMERICA
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A ProMED-mail post

In this update:
[1] USA - MMWR
[2] USA, Mexico - WHO

[1] USA - MMWR
Date: 24 Apr 2009
Source: MMWR Morb Mortal Wkly Rep Dispatch 24 Apr 2009/58 (dispatch);1-3
<http://cdc.gov/mmwr/preview/mmwrhtml/mm58d0424a1.htm>


Update: swine influenza A (H1N1) infections --- California and Texas, April 2009
--------------------
On [21 Apr 2009], CDC reported that 2 recent cases of febrile respiratory illness in children in southern California had been caused by infection with genetically similar swine influenza A (H1N1) viruses. The viruses contained a unique combination of gene segments that had not been reported previously among swine or human influenza viruses in the United States or elsewhere (1). Neither child had known contact with pigs, resulting in concern that human-to-human transmission might have occurred.

The seasonal influenza vaccine H1N1 strain is thought to be unlikely to provide protection. This report updates the status of the ongoing investigation and provides preliminary details about 6 additional persons infected by the same strain of swine influenza A (H1N1) virus identified in the previous cases, as of [24 Apr 2009]. The 6 additional cases were reported in San Diego County, California (3 cases), Imperial County, California (one case), and Guadalupe County, Texas (2 cases). CDC, the California Department of Public Health, and the Texas Department of Health and Human Services are conducting case investigations, monitoring for illness in contacts of the 8 patients, and enhancing surveillance to determine the extent of spread of the virus. CDC continues to recommend that any influenza A viruses that cannot be subtyped be sent promptly for testing to CDC. In addition, swine influenza A (H1N1) viruses of the same strain as those in the US patients have been confirmed by CDC among specimens from patients in Mexico. Clinicians should consider swine influenza as well as seasonal influenza virus infections in the differential diagnosis for patients who have febrile respiratory illness and who 1) live in San Diego and Imperial counties, California, or Guadalupe County, Texas, or traveled to these counties or 2) who traveled recently to Mexico or were in contact with persons who had febrile respiratory illness and were in one of the 3 US counties or Mexico during the 7 days preceding their illness onset.

Case reports
------------
San Diego County, California. On [9 Apr 2009], an adolescent girl aged 16 years and her father aged 54 years went to a San Diego County clinic with acute respiratory illness. The youth had onset of illness on [5 Apr 2009].
Her symptoms included fever, cough, headache, and rhinorrhea. The father had onset of illness on [6 Apr 2009] with symptoms that included fever, cough, and rhinorrhea. Both had self-limited illnesses and have recovered. The father had received seasonal influenza vaccine in October 2008; the daughter was unvaccinated. Respiratory specimens were obtained from both, tested in the San Diego County Health Department Laboratory, and found to be positive for influenza A using reverse transcription--polymerase chain reaction (RT-PCR), but could not be further subtyped. Two household contacts of the patients have reported recent mild acute respiratory illnesses; specimens have been collected from these household members for testing. One additional case, in a child residing in San Diego County, was identified on [24 Apr 2009]; epidemiologic details regarding this case are pending.

Imperial County, California. A woman aged 41 years with an autoimmune
illness who resided in Imperial County developed fever, headache, sore
throat, diarrhea, vomiting, and myalgias on [12 Apr 2009]. She was
hospitalized on [15 Apr 2009]. She recovered and was discharged on [22 Apr 2009]. A respiratory specimen obtained [16 Apr 2009] was found to be influenza A positive by RT-PCR at the San Diego Country Health Department Laboratory, but could not be further subtyped. The woman had not been vaccinated against seasonal influenza viruses during the 2008--09 season. Three household contacts of the woman reported no recent respiratory illness.

Guadalupe County, Texas. Two adolescent boys aged 16 years who resided in Guadalupe County near San Antonio were tested for influenza and found to be positive for influenza A on [15 Apr 2009]. The youths had become ill with acute respiratory symptoms on [10 Apr 2009] and [14 Apr 2009], respectively, and both had gone to an outpatient clinic for evaluation on [15 Apr 2009]. Identification and tracking of the youths' contacts is under way.

Five of the new cases were identified through diagnostic specimens collected by the health care facility in which the patients were examined, based on clinical suspicion of influenza; information regarding the 6th case is pending. The positive specimens were sent to public health laboratories for further evaluation as part of routine influenza surveillance in the 3 counties.

Outbreaks in Mexico
-------------------
Mexican public health authorities have reported increased levels of respiratory disease, including reports of severe pneumonia cases and deaths, in recent weeks. Most reported disease and outbreaks are reported from central Mexico, but outbreaks and severe respiratory disease cases also have been reported from states along the US-Mexico border. Testing of specimens collected from persons with respiratory disease in Mexico by the CDC laboratory has identified the same strain of swine influenza A (H1N1) as identified in the US cases. However, no clear data are available to assess the link between the increased disease reports in Mexico and the confirmation of swine influenza in a small number of specimens. CDC is assisting public health authorities in Mexico in testing additional specimens and providing epidemiologic support. None of the US patients traveled to Mexico within 7 days of the onset of their illness.

Epidemiologic and laboratory investigations
-------------------------------------------
As of April 24, epidemiologic links identified among the new cases included 1) the household of the father and daughter in San Diego County, and 2) the school attended by the 2 youths in Guadalupe County. As of April 24, no epidemiologic link between the Texas cases and the California cases had been identified, nor between the 3 new California cases and the 2 cases previously reported. No recent exposure to pigs has been identified for any of the 7 patients. Close contacts of all patients are being investigated to determine whether person-to-person spread has occurred.

Enhanced surveillance for additional cases is ongoing in California and in Texas. Clinicians have been advised to test patients who visit a clinic or hospital with febrile respiratory illness for influenza. Positive samples should be sent to public health laboratories for further characterization.

Seasonal influenza activity continues to decline in the United States, including in Texas and California, but remains a cause of influenza-like illness in both areas.

Viruses from 6 of the 8 patients have been tested for resistance to antiviral medications. All 6 have been found resistant to amantadine and rimantidine but sensitive to zanamivir and oseltamivir.

Reported by: San Diego County Health and Human Svcs; Imperial County Public Health Dept; California Dept of Public Health. Dallas County Health and Human Svcs; Texas Dept of State Health Svcs. Naval Health Research Center; Navy Medical Center, San Diego, California. Animal and Plant Health Inspection Svc, US Dept of Agriculture. Div of Global Migration and Quarantine, National Center for Preparedness, Detection, and Control of Infectious Diseases; Nationl Center for Zoonotic, Vector-Borne, and Enteric Diseases; Influenza Div, National Center for Infectious and Respiratory Diseases, CDC.

Editorial note
--------------
In the US, novel influenza A virus infections in humans, including swine influenza A (H1N1) infections, have been nationally notifiable conditions since 2007. Recent pandemic influenza preparedness activities have greatly increased the capacity of public health laboratories in the US to perform RT-PCR for influenza and to subtype influenza A viruses they receive from their routine surveillance, enhancing the ability of US laboratories to identify novel influenza A virus infections. Before the cases described in this ongoing investigation, recent cases of swine influenza in humans reported to CDC occurred in persons who either had exposure to pigs or to a family member with exposure to pigs. Transmission of swine influenza viruses between persons with no pig exposure has been described previously, but that transmission has been limited (2,3). The lack of a known history of pig exposure for any of the patients in the current cases indicates that they acquired infection through contact with other infected persons.

The spectrum of illness in the current cases is not yet fully defined. In the 8 cases identified to date, 6 patients had self-limited illnesses and were treated as outpatients. One patient was hospitalized. Previous reports of swine influenza, although in strains different from the one identified in the current cases, mostly included mild upper respiratory illness; but severe lower respiratory illness and death also have been reported (2,3).

The extent of spread of the strain of swine influenza virus in this investigation is not known. Ongoing investigations by California and Texas authorities of the 2 previously reported patients, a boy aged 10 years and a girl aged 9 years, include identification of persons in close contact with the children during the period when they were likely infectious (defined as from 1 day before symptom onset to 7 days after symptom onset). These contacts have included household members, extended family members, clinic staff members who cared for the children, and persons in close contact with the boy during his travel to Texas on April 3. Respiratory specimens are being collected from contacts found to have ongoing illness.

In addition, enhanced surveillance for possible cases is under way in clinics and hospitals in the areas where the patients reside. Similar investigations and enhanced surveillance are now under way in the additional 6 cases.

Clinicians should consider swine influenza infection in the differential diagnosis of patients with febrile respiratory illness and who 1) live in San Diego and Imperial counties, California, or Guadalupe County, Texas, or traveled to these counties or 2) who traveled recently to Mexico or were in contact with persons who had febrile respiratory illness and were in one of the 3 US counties or Mexico during the 7 days preceding their illness onset. Any unusual clusters of febrile respiratory illness elsewhere in the United States also should be investigated.

Patients who meet these criteria should be tested for influenza, and specimens positive for influenza should be sent to public health laboratories for further characterization. Clinicians who suspect swine influenza virus infections in humans should obtain a nasopharyngeal swab from the patient, place the swab in a viral transport medium, refrigerate the specimen, and then contact their state or local health department to facilitate transport and timely diagnosis at a state public health laboratory. CDC requests that state public health laboratories promptly send all influenza A specimens that cannot be subtyped to the CDC, Influenza Division, Virus Surveillance and Diagnostics Branch Laboratory. As a precautionary step, CDC is working with other partners to develop a vaccine seed strain specific to these recent swine influenza viruses in humans.

As always, persons with febrile respiratory illness should stay home from work or school to avoid spreading infections (including influenza and other respiratory illnesses) to others in their communities. In addition, frequent hand washing can lessen the spread of respiratory illness (5). Interim guidance on infection control, treatment, and chemoprophylaxis for swine influenza is available at
<http://www.cdc.gov/flu/swine/recommendations.htm>. Additional information about swine influenza is available at <http://www.cdc.gov/flu/swine/index.htm>.

References
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1. CDC. Swine influenza A (H1N1) infection in two children -- Southern
California, March-April 2009. MMWR 2009; 58: 400-2. [available at
<http://cdc.gov/mmwr/preview/mmwrhtml/mm5815a5.htm>
2. Myers KP, Olsen CW, Gray GC. Cases of swine influenza in humans: a
review of the literature. Clin Infect Dis 2007; 44: 1084-8.
3. Wells DL, Hopfensperger DJ, Arden NH, et al. Swine influenza virus
infections. Transmission from ill pigs to humans at a Wisconsin
agricultural fair and subsequent probable person-to-person transmission. JAMA 1991; 265: 478-81.
4. Newman AP, Reisdorf E, Beinemann J, et al. Human case of swine influenza A (H1N1) triple reassortant virus infection, Wisconsin. Emerg Infect Dis 2008; 14: 1470-2.
5. Ryan MA, Christian RS, Wohlrabe J. Handwashing and respiratory illness among young adults in military training. Am J Prev Med 2001; 21: 79-83.

[Reasonable Rascal]

INFLUENZA A (H1N1) VIRUS, SWINE, HUMAN - NORTH AMERICA (02)
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A ProMED-mail post

Update:
[1] and [2] Strain identity
[3] Pandemic warning
[4] Outbreak in NY ?

******
[1] Strain identity
Date: Fri 24 Apr 2009
Source: CIDRAP News [edited]
<http://www.cidrap.umn.edu/cidrap/content/influenza/panflu/news/apr2409swine.html>

Labs confirm same swine flu in deadly Mexican outbreaks
-------------------------------------------------------
Samples from a deadly respiratory illness outbreak in Mexico match swine influenza isolates from patients in the United States who had milder illnesses, an official from the US Centers for Disease Control and Prevention (CDC) said today [24 Apr 2009], fueling speculation that the World Health Organization (WHO) could be on the verge of raising the global pandemic alert level. Richard Besser, MD, CDC's acting director, told reporters today during a press teleconference that the development is worrisome. "Our concern has grown since yesterday, based on what we've learned," he said. "We do not know if this will lead to the next pandemic, but our scientists are monitoring it and take the threat very seriously."

The swine flu A/H1N1 strain has been confirmed in one more US citizen, a child from San Diego who has recovered, raising the total number of US cases to 8, Besser said. The virus contains gene segments from 4 different influenza types: North American swine, North American avian, human, and Eurasian swine.

WHO said today that Mexican officials have reported 3 separate events. In the Federal District, the number of cases rose steadily through April, and as of yesterday, more than 854 cases of pneumonia, 59 of them fatal, had been reported in Mexico City. The illness outbreak in Mexico City prompted the country's health minister, Jose Cordova, to cancel classes in Mexico City today and advise students and adults to avoid crowded public places and large events, Bloomberg News reported. Mexican officials also reported 24 cases with 3 deaths from an influenza-like illness in San Luis Potosi, in the central part of the country, and 4 cases with no deaths in Mexicali, near the US border, WHO reported.

The virus in Mexico has primarily struck otherwise healthy young adults, WHO said, which is a departure from seasonal influenza, which typically affects the very young and very old. CDC's laboratory analyzed 14 samples from severely ill Mexican patients and found that 7 of them had the same swine flu mix as the virus that infected the US patients. Besser called the analysis preliminary, however, and said that CDC doesn't yet have enough information to draw conclusions. "We still don't have enough information about the extent of the spread or the illness spectrum." WHO said today that Canada's national laboratory has confirmed swine flu A/H1N1 in 18 isolates from Mexican patients, 12 of which were genetically identical to the swine flu viruses from California.

WHO and CDC both said they were sending representatives to Mexico to assist local authorities, and WHO said it has alerted its Global Alert and Response Network. Besser said that WHO will likely convene an expert panel to discuss raising the pandemic alert level from 3 (human infection with new influenza subtype with only rare human-to-human spread) to 4 (small clusters with localized human-to-human transmission). He said the experts will consider 3 factors: the novelty of the virus, disease severity, and how easily transmission of the virus is sustained. Global health officials might consider a containment strategy such as dispatching antiviral medications to affected parts of Mexico in an attempt to stop the spread of the virus, but Besser said that such a measure might not work, because there are signs that the virus has already spread from human to human over long distances. "A focused, well defined area is not something we've seen here," he said. CDC officials have said the swine flu A/H1N1 virus is susceptible to the newer antivirals oseltamivir (Tamiflu) and zanamivir (Relenza), but not the older ones, amantadine and rimantadine. Jeff McLaughlin, a spokesman for GlaxoSmithKline, the maker of Relenza, told CIDRAP News that the company is watching the swine flu developments closely. Terry Hurley, a spokesman for Roche, which produces Tamiflu, said its "rapid response stockpile" is on 24-hour standby, as usual, for deployment to WHO, which has not yet requested it.

The threat from the swine flu virus serves as a reminder for individuals and businesses to think about their own level of preparedness, Besser said.

"This is a time for people to be thinking about that teachable moment." So far, federal officials have not changed their travel recommendations to California, Texas, or Mexico, though they have issued an advisory about the increased health risk in certain parts of Mexico, urging travelers to take standard precautions such hand washing, staying home when sick, and using good coughing and sneezing hygiene.

[byline: Lisa Schnirring]

--
communicated by:
ProMED-mail

[The "swine" influenza A(H1N1) virus associated with current outbreaks of respiratory illness in the southern region of the USA and in Mexico appears to be a complex reassortant containing genome components from avian, human, and swine virus sources. Such a virus is unique and it is too early to conclude that this virus has originated in swine.

According to the CDC website (<http://www.cdc.gov/swineflu/>) swine
influenza (swine flu) is a respiratory disease of pigs caused by type A
influenza viruses that regularly cause outbreaks of influenza among pigs.

Swine flu viruses do not normally infect humans; however, human infections with swine flu do occur, and cases of human-to-human spread of swine flu viruses has been documented. From December 2005 through February 2009, a total of 12 human infections with swine influenza were reported from 10 states in the United States. Since March 2009, a number of confirmed human cases of the new strain of swine influenza A (H1N1) virus infection in California, Texas, and Mexico have been identified.

Whatever the origin of the current outbreak virus it is likely that the
designation swine influenza virus will stick. - Mod.CP]

******
[2] Strain identity
Date: Fri 24 Apr 2009
Source: CBC News [abbreviated and edited]
<http://www.cbc.ca/health/story/2009/04/24/health-flu-mexico090424.html>

Canadian lab confirms human swine flu cases in Mexico
-----------------------------------------------------
"Today we have received results which confirm that the virus is human swine influenza," Leona Aglukkaq told a press conference in Ottawa, Ontario, Canada. A handful of cases of flu-like illness in Canadian residents who recently returned from Mexico are being monitored; however, "there have been no confirmed cases of human swine influenza yet" here, said Dr David Butler-Jones, Canada's chief public health officer.

Mexico sent 51 specimens for testing to Canada's National Microbiology
Laboratory on Wednesday [21 Apr 2009]. 16 positives of swine flu were found among the samples. Mexican health minister Jose Angel Cordova said on Friday that 20 people were killed in the outbreak and 1004 were infected throughout the country, prompting WHO to convene an emergency meeting on Saturday. Officials closed schools, museums and libraries in Mexico City on Friday to limit spread of the virus.

Dr Rich Besser, acting head of the US Centers for Disease Control (CDC), said early analysis of Mexican samples of the virus showed it is very similar to those responsible for 8 American cases, one confirmed on Friday. All the US victims have recovered. Canada is working with Mexican and US health officials to confirm that the virus in both countries is linked and is in fact a new strain of influenza A H1N1 human swine virus, he added.

"This is an interesting virus. It's a brand new virus, not only to humans but to the world," said Dr Frank Plummer, scientific director of the Winnipeg lab. "About 80 per cent of the virus is highly related to a North American body [?] of swine flu that's been around for a number of years, but about 20 per cent of it comes from an Eurasian variety of swine flu 1st seen in Thailand, so it's recombined [re-assorted ?] to create something totally new. How it did that, where it did it, when it did it, I don't think we know yet."

CDC said the current strain of swine flu includes genetic material from 4 sources: North American swine influenza viruses, North American avian
influenza viruses, human influenza virus, and swine influenza viruses found in Asia and Europe -- a new combination that has not been recognized anywhere in the world before. There appears to be human-to-human spread in both the US and Mexico over a wide geographic area at this point, but investigators are still checking for direct contact with swine.

WHO spokesperson Gregory Hartl said the agency needs to determine whether the outbreaks constitute an international public health threat. Hartl also said 12 of 18 samples taken from victims in Mexico showed the virus had a genetic structure identical to that of the virus found in California earlier this week. But he said the agency needs more information before it changes its pandemic alert level, which currently stands at 3 on a scale of one to 6. The virus was 1st reported earlier this week as US health officials scrambled to deal with the diagnoses of 7 people with the never-before-seen strain in Texas and California. The states share a border with Mexico not far from a town where 2 deaths were reported.

Hartl said health officials are dealing with 3 separate events in Mexico, with most of the cases in and around the capital, Mexico City. Most of the cases have occurred in healthy young adults, he added. "Because these cases are not happening in the very old or the very young, which is normal with seasonal influenza, this is an unusual event and a cause for heightened concern," Hartl said in an interview from WHO headquarters in Geneva. It is also rare to see such high flu activity so late in the season, he said. "The end of April, especially in a place like Mexico, you would think that we would see quite a steep decline," said Hartl.

On Thursday [23 Apr 2009], Canadian health officials issued advice warning travellers who have recently returned from Mexico to be on alert for flu-like symptoms that could be connected to the illness.

--
communicated by:
Steven McAuley
Medical student
University of Otago
Dunedin, New Zealand

******
[3] Pandemic warning
Date: Sat 25 Apr 2009
Source: MSNBC [edited]
<http://www.msnbc.msn.com/id/30398682>

Health officials prepare for swine flu "pandemic"
-------------------------------------------------
A new swine flu strain that has killed as many as 68 people and sickened more than 1000 across Mexico has "pandemic potential," the WHO chief said on Saturday [25 Apr 2009], and it may be too late to contain the sudden outbreak. CDC has stepped up surveillance across the United States. "We are worried," said CDC's Dr Anne Schuchat. "We don't think we can contain the spread of this virus," said Schuchat, interim deputy director for the Science and Public Health Program. "We are likely to find it in many other places." Because cases have been detected in California, Texas, and in several sites in Mexico, officials now must work to detect infections and reduce their severity, if possible. "It's time to prepare, time to think ahead and to be prepared for some uncertainty," she told reporters in a telephone briefing on Saturday.

Two dozen new suspected cases were reported Saturday [25 Apr 2009] in
Mexico City alone. Schools were closed and all public events suspended in the capital until further notice -- including more than 500 concerts and other gatherings in the metropolis of 20 million. A hot line fielded 2366 calls in its 1st hours from frightened city residents who suspected they might have the disease. Soldiers and health workers handed out masks at subway stops, and hospitals dealt with crowds of people seeking help.

WHO's director-general, Margaret Chan, said the outbreak of the
never-before-seen virus is a very serious situation and has "pandemic
potential". But she said it is still too early to tell if it would become a pandemic. "The situation is evolving quickly," Chan said in a telephone news conference in Geneva. "A new disease is by definition poorly understood. "This virus is a mix of human, pig, and bird strains that prompted the WHO to meet Saturday to consider declaring an international public health emergency -- a step that could lead to travel advisories, trade restrictions and border closures. Spokesman Gregory Hartl said a decision would not be made on Saturday.

Scientists have warned for years about the potential for a pandemic from viruses that mix genetic material from humans and animals. Another reason to worry is that authorities said the dead so far don't include vulnerable infants and elderly. The Spanish flu pandemic, which killed at least 40 million people worldwide in 1918-19, also 1st struck otherwise healthy young adults. This swine flu and regular flu can have similar symptoms -- mostly fever, cough, and sore throat, though some of the US victims who recovered also experienced vomiting and diarrhea. But unlike with regular flu, humans don't have natural immunity to a virus that includes animal genes -- and new vaccines can take months to bring into use.

But experts at WHO and CDC say the nature of this outbreak may make
containment impossible. Already, more than 1000 people have been infected in as many as 14 of Mexico's 32 states, according to daily newspaper El Universal. Tests show 20 people have died of the swine flu, and 48 other deaths were probably due to the same strain.

CDC and Canadian health officials were studying samples sent from Mexico, and airports around the world were screening passengers from Mexico for symptoms of the new flu strain, saying they may quarantine passengers. But CDC officials dismissed the idea of trying that in the United States. They noted there had been no direct contact between the cases in the San Diego and San Antonio areas, suggesting the virus had already spread from one geographic area through other undiagnosed people. "Anything that would be about containing it right now would purely be a political move," said Michael Osterholm, a University of Minnesota pandemic expert.

Mexican President Felipe Calderon said his government only discovered the nature of the virus late on Thursday, with the help of international laboratories. "We are doing everything necessary," he said in a brief statement. But the government had said for days that its growing flu caseload was nothing unusual, so the sudden turnaround angered many who wonder if Mexico missed an opportunity to contain the outbreak.

Across Mexico's capital, residents reacted with fatalism and confusion, anger, and mounting fear at the idea that their city may be ground zero for a global epidemic. Authorities urged people to stay home if they feel sick and to avoid shaking hands or kissing people on the cheeks.

--
communicated by:
Charles H Calisher, PhD
Professor, Arthropod-borne and Infectious Diseases Laboratory
Department of Microbiology, Immunology and Pathology
3195 Rampart Rd, Delivery Code 1690, Foothills Campus
Fort Collins, CO 80523-1690
College of Veterinary Medicine and Biomedical Sciences
Colorado State University

******
[4] Suspected outbreak in New York
Date: Fri 24 Apr 2009
Source: WCBS TV News [edited]
<http://wcbstv.com/health/swine.flu.nyc.2.994071.html>

Possible swine flu outbreak at NYC prep school
----------------------------------------------
New York City health officials say that about 75 students at a Queens high school have fallen ill with flu-like symptoms and testing is under way to rule out the strain of swine flu that has killed dozens in Mexico. The Health Department's Dr Don Weiss said on Friday [24 Apr 2009] that a team of agency doctors and investigators were dispatched to the private St Francis Preparatory School the previous day after students reported fever, sore throat, cough, aches, and pains. No one has been hospitalized.

The handful of sick students who remained at the school were tested for a variety of flu strains. If they're found to have a known human strain that would rule out swine flu. Results could take several days. In the meantime, the school says it's postponing an evening event and sanitizing the building over the weekend.

Mexican authorities said 60 people may have died from a swine flu virus in Mexico, and world health officials worry it could unleash a global flu epidemic. Mexico City closed schools, museums, libraries, and state-run theaters across the metropolis on Friday in hopes of containing the outbreak that has sickened more than 900. The US Centers for Disease Control and Prevention (CDC) said tests show some of the Mexico victims died from the same new strain of swine flu that sickened 8 people in Texas and California. It's a frightening new strain that combines genetic material from pigs, birds and humans.

WHO was looking closely at the 60 deaths -- most of them in or near
Mexico's capital. It wasn't yet clear what flu they died from, but spokesman Thomas Abraham said "We are very, very concerned. We have what appears to be a novel virus and it has spread from human to human," he said. "It's all hands on deck at the moment."

WHO raised its internal alert system on Friday, preparing to divert more money and personnel to dealing with the outbreak. President Felipe Calderon cancelled a trip and met with his Cabinet to coordinate Mexico's response. The government has 500 000 flu vaccines and planned to administer them to health workers, the highest risk group. There are no vaccines available for the general public in Mexico, and authorities urged people to avoid hospitals unless they had a medical emergency, since hospitals are centers of infection. Some Mexican residents have started wearing blue surgical masks for extra protection, reports CBS News correspondent Adrienne Bard. The federal health minister has warned people not to go near anyone with a respiratory infection and to avoid kissing -- a traditional Mexican greeting.

--
communicated by:
ProMED-mail rapporteur Mary Marshall

[If infection by the novel swine flu virus is confirmed, it will represent a dramatic extension of the range of the outbreak virus from the southern states and Mexico to the north east of the United States. There is no reason to conclude at present, however, that this is anything other than an outbreak of seasonal influenza virus infection (or for that matter another common respiratory virus). - Mod.CP]

[Reasonable Rascal]

INFLUENZA A (H1N1) VIRUS, SWINE, HUMAN - NORTH AMERICA (03)
************************************************** *********
A ProMED-mail post

In this update:
[1] WHO - Public Health Emergency of International Concern
USA
[2] CDC update
[3] New York City
[4] Kansas
Mexico
[5] Mexico
Elsewhere in the news:
[6] UK - flight attendant ex Mexico, suspected

******
[1] WHO - Public Health Emergency of International Concern
Date: 25 Mar 2009
Source: WHO website [edited]
<http://www.who.int/mediacentre/news/statements/2009/h1n1_20090425/en/index.html>

Statement by WHO director-general, Dr Margaret Chan [25 Apr 2009]
Swine influenza
---------------
In response to cases of swine influenza A(H1N1), reported in Mexico and the United States of America, the director-general convened a meeting of the Emergency Committee to assess the situation and advise her on appropriate responses. The establishment of the committee, which is composed of international experts in a variety of disciplines, is in compliance with the International Health Regulations (2005). The 1st meeting of the Emergency Committee was held on Saturday [25 Apr 2009].

After reviewing available data on the current situation, committee members identified a number of gaps in knowledge about the clinical features, epidemiology, and virology of reported cases and the appropriate responses. The committee advised that answers to several specific questions were needed to facilitate its work. The committee nevertheless agreed that the current situation constitutes a public health emergency of international concern.

Based on this advice, the director-general has determined that the current events constitute a public health emergency of international concern, under the regulations. Concerning public health measures, in line with the regulations the director-general is recommending, on the advice of the committee, that all countries intensify surveillance for unusual outbreaks of influenza-like illness and severe pneumonia. The committee further agreed that more information is needed before a decision could be made concerning the appropriateness of the current phase 3.

Related links:
Swine influenza: <http://www.who.int/csr/disease/swineflu/en/index.html>
Current WHO phase of pandemic alert:
<http://www.who.int/csr/disease/avian_influenza/phase/en/index.html>
International Health Regulations (IHR): <http://www.who.int/ihr/en/index.html>

--
communicated by:
Kunihiko Iizuka

******
[2] USA - CDC update
Date: 25 Apr 2009
Source: CDC website [edited]
<http://www.cdc.gov/swineflu/investigation.htm>

Human swine influenza investigation: [25 Apr 2009] 19:30 EDT
------------------------------------------------------------
Human cases of swine influenza A (H1N1) virus infection have been
identified in the US in San Diego County and Imperial County, California as well as in San Antonio, Texas. Internationally, human cases of swine influenza A (H1N1) virus infection have been identified in Mexico.

US human cases of swine flu infection
-------------------------------------
State: No. of laboratory confirmed cases
California: 7 cases
Texas: 2 cases
Kansas: 2 cases
Total count: 11 cases (as of April 25th, 2009 7:30 pm EDT)

Investigations are ongoing to determine the source of the infection and
whether additional people have been infected with similar swine influenza viruses.

CDC is working very closely with state and local officials in California, Texas, as well as with health officials in Mexico, Canada and the World Health Organization. On [24 Apr 2009], CDC deployed 7 epidemiologists to San Diego County, California and Imperial County, California and 1 senior medical officer to Texas to provide guidance and technical support for the ongoing epidemiologic field investigations. CDC has also deployed to Mexico 1 medical officer and 1 senior expert who are part of a global team that is responding to the outbreak of respiratory illnesses in Mexico.

Influenza is thought to spread mainly person-to-person through coughing or sneezing of infected people. There are many things you can to do preventing getting and spreading influenza:

There are everyday actions people can take to stay healthy.
* Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
* Wash your hands often with soap and water, especially after you cough or sneeze. Alcohol-based hands cleaners are also effective.
* Avoid touching your eyes, nose or mouth. Germs spread that way. Try to avoid close contact with sick people.
* Influenza is thought to spread mainly person-to-person through coughing or sneezing of infected people.
* If you get sick, CDC recommends that you stay home from work or school and limit contact with others to keep from infecting them.

--
communicated by:
ProMED-mail

******
[3] USA - New York City
Date: 25 Apr 2009
Source: New York City Department of Health Press Release [edited]
<http://www.nyc.gov/html/doh/html/pr2009/pr015-09.shtml>

Probable cases of swine influenza found in students at school in Queens
-----------------------------------------------------------------------
The Health Department is investigating a cluster of respiratory illness in a non-public school in New York City and has determined that at least 8 students have probable human swine influenza. More than 100 of the school’s students were absent several days this week due to fever, sore throats, and other flu-like symptoms. The Health Department has interviewed more than 100 students or their families, and all students have had mild symptoms; none have been hospitalized. Some family members have developed similar symptoms, suggesting spread in the family.

In response to confirmed cases of swine influenza (swine flu) in Mexico, California and Texas, the New York City Health Department is working closely with the Centers for Disease Control and Prevention (CDC) to assess the possibility of the spread of swine flu. Swine flu is a respiratory infection caused by influenza type A viruses that regularly cause outbreaks of influenza in pigs. People do not normally get swine flu, but human infections can occur. Human cases typically involve people who have had direct contact with pigs, but person-to-person transmission is suspected among recent cases in the south west.

The cases in Mexico have had a high fatality rate, but the 8 recently
confirmed cases from California and Texas have been mild. All of the
non-NYC patients have recovered.

The Health Department’s Public Health Laboratory has completed preliminary viral testing on nose and throat swabs from 9 affected students. Eight of the 9 tests are positive for influenza A. Because they do not match H1 and H3 human subtypes of influenza A by available testing methods, they are considered probable cases of swine flu. The specimens have been sent to the CDC in Atlanta for confirmatory testing. Results of those tests are expected on Sunday [26 Apr 2009]. (The attached chart outlines the steps required for confirmation.)

Patients experiencing severe symptoms, such as difficulty breathing, should seek health care and treatment. Otherwise, the Health Department recommends at-home care. If affected students at the school in question have household contacts at high risk for complications from influenza -- young children, the elderly, and people with chronic illness -- those at risk should receive preventive treatment. The most effective way to lower the risk of transmission is for people with symptoms to stay home. All New Yorkers should cover their mouths when they cough.

Swine influenza cannot be transmitted from eating pork or pork products. The symptoms of swine flu in people appear to be similar to the symptoms of regular human flu and include fever, cough, sore throat, body aches, headache, chills, and fatigue. Some people have reported diarrhea and vomiting associated with swine flu. Like seasonal flu, swine flu may cause a worsening of underlying chronic medical conditions.

For facts about influenza, and more information about swine flu, please
visit the Health Department and CDC websites. Some specific resources:
From New York City Health Department: Facts about flu
<http://www.nyc.gov/html/doh/html/cd/cdinflu.shtml>
From Centers for Disease Control and Prevention:
General information about swine flu
<http://www.cdc.gov/swineflu/general_info.htm>
Swine flu case definitions <http://www.cdc.gov/swineflu/casedef_swineflu.htm>
Swine flu infection control and patient care
<http://www.cdc.gov/swineflu/guidelines_infection_control.htm>
Preventing the flu <http://www.cdc.gov/flu/protect/habits.htm>
Chart: steps required to confirm suspected cases of swine flu
<http://www.nyc.gov/html/doh/html/pr2009/pr015-09.shtml>

Contact: (212) 788-5290
Jessica Scaperotti/Erin Brady: PressOffice@health.nyc.gov

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******
[4] USA - Kansas
Date: 25 Apr 2009
Source: Kansas Department of Health and Environment (KDHE) [edited]
<http://www.kdheks.gov/swineflu/09-060%20Swine%20Flu%20News%20Release.pdf>

KDHE reports 2 cases of swine flu in Kansas
-------------------------------------------
The Kansas Department of Health and Environment (KDHE) announced today that 2 cases of swine flu have been confirmed in Kansas involving 2 adults residing in the same household in Dickinson County. Neither of the patients was hospitalized - one is still ill and being treated, and one is recovering.

One of the patients had recently traveled to Mexico, flying in and out of Wichita. Both persons work in Saline County and became ill with the same unique (H1N1) strain of swine flu that has been identified in Mexico, California, and Texas. "It’s not yet known whether this will become the next flu pandemic," stated Dr Jason Eberhart-Phillips, state health officer and director of the KDHE Division of Health. "We are working closely with health agencies at all levels and are continuing to monitor these cases. We are taking this situation very seriously."

KDHE and the Dickinson County Health Department are investigating the
sources of exposure, and efforts are being coordinated with CDC.
Individuals who have been in contact with the patients are being
interviewed and tested. Local health departments and hospitals in Kansas are being continuously updated and provided with information about the swine flu virus.

In accordance with the Kansas Response Plan, KDHE is also monitoring and instituting recommendations from CDC for any additional influenza disease surveillance activities, reviewing plans to further enhance those activities, and advising health care providers to use rapid detection tests for persons who have symptoms consistent with swine flu, especially if they have recently been in Mexico, and taking other steps under the plan.

The KDHE Office of Surveillance and Epidemiology received a report of
unusual flu-like illness from Dickinson County on Friday [24 Apr 2009]
afternoon. Respiratory specimens were collected from both patients and
received by KDHE later on Friday evening. At about 2 am Saturday, the
Kansas Health and Environmental Laboratories at KDHE reported preliminary results that were positive for influenza A viruses. Between about 2:30 and 3 am, KDHE notified the Dickinson County Health Department of those preliminary results, which notified the attending physician.

Around that same time, KDHE obtained the use of Governor Kathleen Sebelius’ plane to safely and securely transport the samples as rapidly as possible to the CDC labs in Atlanta for confirmatory analysis to determine if the viruses were of the (H1N1) strain. A staff member with the KDHE Center for Public Health Preparedness handed the samples to a CDC representative at about 6:10 am on Saturday, and the samples reached the labs at about 6:30 am KDHE convened staff in its Department Operations Center at 10 am on Saturday, and was notified by CDC of the confirmatory results at 2:30 pm.

Prior to the recent outbreak in Mexico and the US, since 2005 12 cases of human infection with swine influenza had been reported to CDC. Swine flu infections in humans are rare, but are related to close proximity to infected pigs, such as in pig production barns and livestock exhibits at fairs. Neither of the current patients in Kansas reported having contact with pigs.

For more information and updates, please visit the KDHE website at
<www.kdheks.gov>.
Office of Communications
Curtis State Office Building, 1000 SW Jackson
Street, Suite 540, Topeka, KS 66612-1368
Contact: Maggie Thompson
<http://www.kdheks.gov>

--
communicated by:
Philip Henika <philiphe@yahoo.com>
ProMED-mail rapporteur Mary Marshall
ProMED-mail

******
[5] Mexico
Date: 25 Apr 2009 [edited]
Source: Yahoo News / Associated Press
<http://news.yahoo.com/s/ap/20090426/ap_on_re_la_am_ca/med_swine_flu>

Mexico fights swine flu with "pandemic potential"
-------------------------------------------------
Mexico's president assumed new powers Saturday to isolate people infected with a deadly swine flu strain as authorities struggled to contain an outbreak that world health officials warned could become a global epidemic.

New cases of swine flu were confirmed in Kansas and California and
suspected in New York City. But officials said they didn't know whether the New York cases were the strain that now has killed up to 81 people in Mexico and likely sickened 1324 since [13 Apr 2009], according to figures updated late Saturday [25 Apr 2009] by Mexico's health secretary. Tests have confirmed swine flu as the cause of death in 20 of the cases.

Mexican soldiers and health workers patrolled airports and bus stations as they tried to corral people who may be infected with the swine flu, as it became clearer that the government may have been slow to respond to the outbreak in March and early April [2009].

Now, even detaining the ill may not keep the strain -- a combination of
swine, bird and human influenza that people may have no natural immunity to -- from spreading, epidemiologists say. The World Health Organization on Saturday [25 Apr 2009] asked countries around the world to step up reporting and surveillance of the disease and implement a coordinated response to contain it.

Two dozen new suspected cases were reported in Mexico City alone, where
authorities suspended schools and all public events until further notice. More than 500 events, including concerts and sports games, were canceled in the metropolis of 20 million. Mexican authorities ordered schools closed in the capital and the states of Mexico and San Luis Potosi until [6 May 2009], and the Roman Catholic Church announced the cancellation of Sunday masses in the capital.

The Mexican government issued a decree authorizing President Felipe
Calderon to invoke special powers letting the Health Department isolate
patients and inspect homes, incoming travelers and baggage. But officials said it was designed to free health workers from possible legal reprisals and to speed disease control efforts.

A team from the Centers for Disease Control had arrived in Mexico to help set up detection testing for the swine flu strain, something Mexico previously lacked. The US Embassy said the US has not imposed travel constraints to and from Mexico but is suspending the processing of visas and other services through Wednesday [29 Apr 2009] to avoid creating crowds. It issued an earlier message advising US citizens to avoid large crowds, shaking hands, greeting people with a kiss or using the subway.

While suspected swine flu cases have been reported in about 16 Mexican
states, health secretary Jose Cordova said "it has not spread to the entire country."

WHO director-general Margaret Chan said the outbreak of the
never-before-seen virus has "pandemic potential." But she said it is still too early to tell if it would become a pandemic. WHO lays out 3 criteria necessary for a global epidemic: The virus is able to infect people, can readily spread person-to-person, and the global population has no immunity to it.

Early detection and treatment are key to stopping any outbreak. WHO
guidance calls for isolating the sick and blanketing everyone around them with anti-viral drugs such as Tamiflu [oseltamivir]. Now, with patients showing up all across Mexico and its teeming capital, simple math suggests that kind of response is impossible. Mexico appears to have lost valuable days or weeks in detecting the new virus. Health authorities started noticing a threefold spike in flu cases in late March and early April [2009], but they thought it was a late rebound in the December-February flu season. Testing at domestic labs did not alert doctors to the new strain, and Cordova acknowledged Mexican labs lacked the necessary profiling data to detect the previously unknown strain.

The 1st death occurred in southern Oaxaca state on [13 Apr 2009], but
Mexico didn't send the 1st of 14 mucous samples to CDC until [18 Apr 2009], around the same time it dispatched health teams to hospitals looking for patients with severe flu or pnuemonia-like symptoms. Those teams noticed something strange: the flu was killing people aged 20 to 40. Flu victims are usually either infants or the elderly. The Spanish flu pandemic, which killed at least 40 million people worldwide in 1918-19, also 1st struck otherwise healthy young adults.

Even though US labs detected the swine flu in California and Texas before last weekend, Mexican authorities as recently as Wednesday [22 Apr 2009] were referring to it as a late-season flu. But mid-afternoon Thursday [23 Apr 2009], Mexico City health secretary Dr Armando Ahued said, officials got a call "from the United States and Canada, the most important laboratories in the field, telling us this was a new virus."

"That was what led us to realize it wasn't a seasonal virus ... and take more serious preventative measures," Cordova said. Asked why there were so many deaths in Mexico, and none so far among the 11 cases in the United that the US cases involved children -- who haven't been among the fatal cases in Mexico, either. "There are immune factors that are giving children some sort of defense, that is the only explanation we have," he said. Another factor may be that some Mexican patients may have delayed seeking medical help too long, Cordova said. Some Mexicans suspected the government had been less than forthcoming. "They always make a big deal about good things that happen, but they really try to hide anything bad," [a Mexico City paralegal] said.

Airports around the world were screening travelers from Mexico for flu
symptoms. But containing the disease may not be an option. "Anything that would be about containing it right now would purely be a political move," said Michael Osterholm, a University of Minnesota pandemic expert. Scientists have warned for years about the potential for a pandemic from viruses that mix genetic material from humans and animals. This swine flu and regular flu can have similar symptoms -- mostly fever, cough and sore throat, though some of the US victims who recovered also experienced vomiting and diarrhea. But unlike with regular flu, humans don't have natural immunity to a virus that includes animal genes -- and new vaccines can take months to bring into use.

A "seed stock" genetically matched to the new swine flu virus has been
created by CDC, said Dr Richard Besser, the agency's acting director. If the government decides vaccine production is necessary, manufacturers would need that stock to get started.

Mexican authorities did lay to rest one persistent doubt, after Mexican
museum director Felipe Solis died this week, just days after accompanying US President Barack Obama on a tour of National Anthropology Museum on [16 Apr 2009]. Cordova said Solis had a pre-existing illness and died of pneumonia unrelated to influenza.

[bylines: Mark Stevenson. (David Koop in Mexico City; Frank Jordans in
Geneva; Mike Stobbe in Atlanta; Malcolm Ritter in New York; and Maria Cheng in London contributed to this report.)]

--
communicated by:
Sara M Volk, PhD,
Postdoctoral Fellow, Alphavirus Pathogenesis and Evolution
Department of Pathology
Center for Biodefense and Emerging Infectious Diseases:
<http://www.utmb.edu/CBEID/virology.shtml>
University of Texas Medical Branch
Galveston, Texas, USA

******
[6] UK - flight attendant ex Mexico, susp
Date: 26 Apr 2009
Source: BBC [edited]
<http://news.bbc.co.uk/2/hi/uk_news/8018887.stm>

UK monitoring swine flu outbreak
--------------------------------
Health officials in the UK say they are closely monitoring the deadly
outbreak of swine flu in Mexico and the US, amid fears of a potential
pandemic. The Health Protection Agency (HPA) said it was working with the government to assess any threat posed to public health in the UK. It described the outbreak as "unusual" and warranting "further investigation and vigilance" by other countries. However, no cases have so far been identified anywhere in Europe.

At least 81 people in Mexico are now thought to have died from pneumonia after contracting swine flu. Swine flu is a respiratory disease that infects pigs and does not normally infect humans. However, sporadic cases do occur, usually in people who have had close contact with pigs.

Precautionary tests
-------------------
WHO said some of those affected in Mexico had tested positive for a strain -- H1N1 -- that had infected at least 7 people in the south western US. The concern is that because this strain appears to be passing easily from human to human, it has the potential to spread rapidly. WHO director-general Margaret Chan said the strain had "pandemic potential" but that it was too early to say whether one would actually occur. The HPA and the NHS have systems in place which will alert public health authorities of any unusual strain circulating in the UK.

Health Protection Authority statement
-------------------------------------
The HPA said: "More investigation and testing is needed to determine the severity of the disease and the ease with which it can spread. "The HPA is monitoring this situation closely and is working with the UK government to review the current incident and any threat it poses to UK public health."

Meanwhile, a male British Airways cabin crew member is undergoing
precautionary tests in a London hospital after falling ill with "flu-like" symptoms on a flight from Mexico City. He was taken to Northwick Park Hospital, in Harrow after landing at Heathrow airport at 1400 BST (1300 GMT) on Saturday [25 Apr 2009]. A hospital spokesman said: "He has flu-like symptoms and is responding well to treatment."The patient was admitted directly to a side room and the hospital is scrupulously following infection-control procedures to ensure there is no risk to any other individual in the hospital." [BBC Radio News at 0900 BST 26 Apr reported that the tests were negative. - Mod.SH]

Antiviral drugs
---------------
The HPA said there was currently a "very low level" of flu activity in the UK, adding that the H1N1 strain at the centre of the American alert was treatable with antiviral drugs such as Tamiflu [oseltamivir] and Relenza [zanamivir]. "The HPA and the NHS have systems in place which will alert public health authorities of any unusual strain circulating in the UK," it said. Britons are not currently being advised to avoid travelling to affected areas of Mexico and the US.

However, the Foreign Office recommends that anyone visiting those
destinations -- or who has recently returned -- should consult a doctor if they experience flu-like symptoms.

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[To summarize the latest findings since the last update:

WHO is now following the guidelines established in the new International Health Regulations (IHR 2005), having convened a meeting of the Emergency Committee, defining the H1N1 (also known as "swine flu") outbreak a "public health emergency of international concern. The current pandemic alert phase is still at level 3 (see the chart with pandemic alert phases available at
<http://www.who.int/csr/disease/avian_influenza/phase/en/index.html>, with a suggestion that this will be watched closely and may be altered depending upon how the situation progresses.

In the USA, there have been cases identified in 2 additional states, New York City (in New York State) and in Kansas. In New York City, there has been an outbreak in a non-public school, with 8 probable cases out of about 200 children with an influenza like illness (ILI) -- these cases had influenza A viruses identified that did not match H1 and H3 human subtypes of influenza A by available testing methods, so they are considered probable cases of swine flu -- and in Kansas there have been 2 cases confirmed, one of whom recently travelled to Mexico. According to the CDC, as of 7 PM EDT (GMT -4), there have been 7 confirmed cases in California and 2 confirmed cases in Texas. With the addition of the 2 cases from Kansas, there have been 11 cases confirmed thus far by the CDC. All cases in the USA have been self limited with full recovery.

In Mexico, the case count is now 1324 (from about 1000 less than 24 hours ago), with 81 reported deaths (up from 60 reported deaths less than 24 hours ago). Newswires describing the situation in Mexico are communicating panic with the addition of significant political overtones, and "spin doctors" are casting stones, blaming cover-ups and slow responses as responsible for the outbreak "escaping", and rumors of implicated swine production farms as the foci where the outbreak allegedly began -- an unfortunate situation that seems to repeat itself every time there is a major outbreak with many unknowns.

From the information that is becoming available, it does appear as though there is significant human to human transmission ongoing of a novel influenza virus. That translates into a large pool of susceptibles for the virus to potentially infect. In the absence of a vaccine that will protect against this novel strain, it is unclear if any measures could have been effectively implemented that would have interrupted transmission earlier. A situation that appears to be a reminder that mother nature is still the most skilled bioterrorist out there.

The suspected case in an airline cabin crew member in the UK, having just returned from Mexico, has -- it seems -- been discounted by initial tests. According to the Health Protection Agency (HPA) of the United Kingdom, as of 25 Apr 2009 there have not been any confirmed cases of this novel H1N1 virus infection in the UK and Europe (see
<http://www.hpa.org.uk/web/HPAweb&HPAwebStandard/HPAweb_C/1240646410227> for the HPA update.

That being said, there are still many unknowns -- will the transmission
chain "burn out" on its own? Are the more severe cases and fatalities
reported from Mexico an indication of a more pathogenic strain for young otherwise healthy individuals or are the reported deaths in individuals with underlying disease? - Mod.MPP]