Human Swine Flu Infection - California & Texas First Report April 21, 2009

[ironorehopper]

The Canadian Press: Unrelated cases of swine flu in Calif. children have U.S. officials on alert

Unrelated cases of swine flu in Calif. children have U.S. officials on alert

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.


Discovery of the two cases, in children who apparently had no contact with pigs or with each other, suggests there probably has been some person-to-person spread of swine flu viruses, officials of the U.S. Centers for Disease Control said Tuesday.

Whether the viruses continue to spread isn't currently known.

"The investigation is not finished. It's ongoing. But of course not having that direct swine link does raise additional questions and does suggest that there may have been human-to-human transmission. And so it basically ratchets it (concern) up a bit," said Dr. Nancy Cox, head of the CDC's influenza division.

"I think this is one of those situations where everyone will want to stay tuned."

U.S. officials notified the World Health Organization of the cases last Friday, as required under the International Health Regulations. That treaty stipulates that countries must notify the WHO when they see cases of infectious diseases that pose an international threat, such as novel subtypes of influenza with pandemic potential.

Dr. Keiji Fukuda, a senior official of the WHO, said there is no need at this point to raise the global pandemic alert level.

The world is currently in phase 3 of a six phase alert scale because of ongoing sporadic cases of H5N1 avian influenza. Phase 3 means there are occasional human cases of influenza with a subtype with pandemic potential, but that there is no ongoing transmission.

"All things considered, based on what we already know about H1 (swine) infections and that they occur, I'm pretty comfortable that the right steps are being taken," said Fukuda, an influenza expert who is the WHO's acting assistant director general for health security and the environment.

Canada became aware of the situation when WHO was notified, said Dr. Arlene King, director general of the Public Health Agency of Canada's centre for immunization and respiratory infectious diseases.

King said no cases of infection with this particular swine flu virus have been spotted in Canada, but the public health network across the country has been put on the lookout.

"The labs are on alert and have been asked to send any non-subtypable influenza viruses ... to the National Microbiology Laboratory for testing and review," King said, adding they have also been asked to report if they can't identify a pathogen found in samples taken from a patient with flu-like symptoms, or have surveillance information indicating unexpected increases in illness.

The cases involved a boy, 10, from San Diego County and a nine-year-old girl from Imperial County, both of whom have recovered from their illnesses.

The two, who live over 150 kilometres apart, became ill at the end of March and sought care from clinics involved in an influenza surveillance program. Those clinics tested for flu; when they found viruses that didn't match known human viruses, they alerted authorities.

Given that most people with flu aren't tested, the CDC's Dr. Lyn Finella called the discovery of the swine flu infections "a very fortunate lightning strike."

Human infections with swine flu viruses are not unprecedented. A scientific paper published in 2007 recorded 50 known cases of human swine flu infections, in the U.S., Canada, the Netherlands and several other countries.

And most famously, a cluster of swine flu cases at Fort Dix, N.J., in 1976 triggered concerns a pandemic might be emerging. Vaccine was made and 47 million people were vaccinated against a pandemic that did not materialize.

Canada sees about one human case of swine flu a year, King said. And the CDC officials said until a couple of years ago, the U.S. averaged one case every year or two. But since December 2005, there have been 14 cases, including these children.In most of the recent cases, direct exposure to pigs could be established. And when cases were caused by H1N1 viruses, those viruses were relatively closely related. Not so in the viruses responsible for the infection in these children.

The viruses, which were described as very similar to one another, have unusual properties never seen before in swine flu viruses, the CDC said.

Two of the genes of the viruses were from swine viruses that normally circulate in Eurasia, a finding that has added to the level of interest and concern. And the hemagglutinin - the H in a flu virus's name - has a lot of mutations when compared to other swine H1N1 viruses, Cox said.

"It's different enough so that we're going to be looking very carefully at properties like receptor binding properties, growth kinetics. We'll be doing some animal model experiments and so on," she noted.

In California, health officials are investigating with help from the CDC, checking the children's contacts and looking for others who may have also been infected.

The CDC said in both cases, two family members were also sick around the time of the confirmed infections, but none of those four people was tested at the time for influenza.

Blood samples have been taken from those four and other people who have been in contact with the children; the blood samples will be tested for antibodies to these swine flu viruses, though results may not be available for some time, Finelli said.

The investigation has also spread to Texas, because the 10-year-old boy travelled by plane on April 3, while he was still ill. He and a brother who travelled with him remain in Texas, the CDC said.

Experts say it is not clear whether a swine flu virus of the H1N1 subtype could trigger a human pandemic at this point in time.

Human H1N1 viruses have been circulating around the world for decades, so there is a lot of immunity to those viruses in the population. But it's not yet known how much protection previous exposure to human H1N1 viruses - or to vaccine made to protect against them - would offer against these novel swine viruses.

"I think that the 100 per cent accurate answer is that nobody knows," Fukuda said from Geneva.

"But I think the other part of that answer is that if there's great enough antigenic distance between the current circulating H1 (human) viruses and for example a swine H1 virus, then there's no reason why it wouldn't behave in a pandemic fashion."

The term "antigenic distance" means how closely related viruses are to each other from the point of view of whether antibodies to one offer cross protection to another. If viruses are antigenically similar, there should be good cross protection.

But if there is great antigenic distance between human H1N1s and these swine flu viruses, the swine viruses would have greater potential to cause human illness.

Cox said that the CDC will be testing blood samples from people of a variety of age groups to try to get a sense of how much of the population might be vulnerable to these viruses. That work, which will take some time, should give a clearer picture of how much of a threat the viruses might pose if they are still circulating.
-

The Canadian Press: Unrelated cases of swine flu in Calif. children have U.S. officials on alert

[vinny]

could this be a major problem if it spreads further..........?

[ironorehopper]

Originally Posted by vinny

could this be a major problem if it spreads further..........?

Everytime a novel influenza virus subtype infects humans, health authorities has the obligation to perform several activities in order to evaluate the risk for the general population.

This incident sees the isolation of a novel swine influenza virus subtype (namely A/H1N1), with the two surface proteins (hemagglutinin (HA) and neurmminidase (NA)) from different origins: the HA is from classical north America swine influenza virus known isolates, whereas NA is from European-like swine isolates; further, M protein is also from European-like lineages.

Human populations have a large immune protection against A/H1N1 seasonal human influenza viruses, but it is unclear whether these antibodies react with this novel subtype, and if yes, the strenght of the response.

In other words, human populations could be susceptible to this novel subtype, paving the way for an outbreak, localized, or more widespread, sparking a possible pandemic.

Until now, no data is available to state that this novel A/H1N1 swine influenza virus will start a pandemic.

For this purpose, US health agencies are testing people for antibodies and tracing contacts for localizing possible clusters of cases and the ''index case''.

At the end of this process, we will be able to know if the virus is readily transmissible and if a pandemic could start at brief or not.

The World Health Organization has been alerted by US authorities according the International Health Regulations rules.

[HenryN]

Originally Posted by vinny

could this be a major problem if it spreads further..........?

I don't think there is any doubt that it has spread further. The two confirmed cases were 100 miles apart and each cluster had multiple symptomatic family members. How far and wide is not known, but spread is virtually guaranteed.
Updated map

http://maps.google.com/maps/ms?ie=UT...2,2.856445&z=8

[HenryN]

2 swine flu cases seen in region

New strain infects children in S.D., Imperial counties

By Keith Darcé (Contact) Union-Tribune Staff Writer
2:00 a.m. April 22, 2009

SWINE FLU

The respiratory disease regularly causes outbreaks among pigs.
Sporadic human infections of swine flu have occurred, mostly through direct exposure to pigs.
About one human case is reported every one to two years in the United States, but the count has risen to 14 cases since December 2005.
Symptoms resemble those of regular human influenza, including fever, lethargy, coughing and nausea.
There is no human vaccine for swine flu.
Source: Centers for Disease Control and Prevention

Federal health officials are asking doctors in San Diego and Imperial counties to take specimens from patients with flulike symptoms after one child in each county recently contracted a new strain of swine flu.
Both children recovered from the illness without hospitalization and no other cases have been identified, but medical experts are concerned because it remains unclear how the children contracted the disease.
Public health officials said the San Diego County case appears to be the first instance of swine flu ever reported in this region. The virus regularly causes outbreaks in pigs but rarely affects humans.
While the federal Centers for Disease Control and Prevention issued a special alert yesterday detailing the latest infections, it said the two cases didn't appear to pose a danger to the public.
“We are not making the assumption that there are widespread infections out there, and there is not any action that the public should take right now,” said Dr. Lyn Finelli, chief of influenza surveillance at the CDC.
The new cases also don't appear to be linked.
“The information we have so far is that (the children) are not related, don't know each other and had no direct association with pigs,” said Dr. Wilma Wooten, San Diego County's public health officer.
Like other types of influenza, swine flu typically creates a mild infection. But its rarity among humans and the lack of a vaccine to protect people from the disease mean that few individuals have antibodies in their blood to fight off the virus.
The strain found in the two children from San Diego and Imperial counties belongs to the same family as one of the seasonal flu viruses that affect humans, but it is genetically similar to a type found in pigs, the CDC said.
Most swine flu cases can be traced to contact between humans and pigs, usually at livestock events or on farms. Of the 14 cases reported in the United States since December 2005, including the two new patients, 11 involved contact with pigs.
In the first new case, a 10-year-old boy in San Diego County started running a fever, coughing and vomiting on March 30, according to the CDC alert. He was taken to a local outpatient clinic where a nasal swab was taken. His symptoms persisted for about a week.
On April 3, the boy flew to Texas with a sibling to visit relatives, CDC spokesman Tom Skinner said. He hasn't returned from the trip.
Federal health officials are monitoring two youngsters who sat near the infected boy on the flight for flu symptoms, and they are tracking down airline crew members who had close contact with the sick child.
The 9-year-old girl in Imperial County became sick March 28 and was taken to an outpatient clinic with a cough and 104-degree fever.
Specimens from both children were forwarded to the CDC last week after local laboratories were unable to match them with common strains of human influenza.
San Diego County's Health and Human Services Agency has deployed a team of epidemiologists, public health nurses and communicable-disease specialists to investigate the source of the infections.
In some cases, the virus is traced to indirect contact with pigs through other people. In other instances, the source is never identified.
“We want to do everything we can to make sure there isn't any person-to-person spread,” Wooten said. “We want to know if there is more virus.”
The Associated Press contributed to this report.

Keith Darce: (619) 293-1020; keith.darce@uniontrib.com
Keith Darcé: (619) 293-1020; (Contact)


http://www3.signonsandiego.com/stori...s-seen-region/

[HenryN]

Swine Flu Detected in 2 Children; Human-to-Human Spread Possible

Emma Hitt, PhD
Authors and Disclosures


April 22, 2009 — H1N1 swine influenza A infection has been reported in 2 children living in southern California. No direct contact with swine was reported in either case, suggesting that the virus may have spread directly among humans.
The cases were reported online April 21 in a special dispatch of the Morbidity and Mortality Weekly Report (MMWR), issued by the US Centers for Disease Control and Prevention (CDC). The swine viruses detected contain combinations of DNA segments not previously observed in influenza virus, and the seasonal influenza vaccine H1N1 strain is unlikely to provide protection, according to the report. The viruses also demonstrated antiviral resistance to amantadine and rimantadine.
According to CDC spokesperson Tom Skinner, it is not yet known whether this swine flu is susceptible to zanamivir (Relenza, GlaxoSmithKline) or oseltamivir (Tamiflu, Roche). "Results of testing should be available within a day or 2," he told Medscape Infectious Diseases in a telephone interview. He added that interim recommendations from the CDC suggest that clinicians should use either oseltamivir or zanamivir if they suspect that a patient has swine flu.
Two Patients Infected
The MMWR report describes 2 patients with swine influenza. One patient was a 10-year-old boy living in San Diego County, California, who traveled by airplane from San Diego to Dallas while sick with flu-like symptoms. These symptoms resolved uneventfully within a week. The patient, who continues to reside in Dallas, tested positive for influ¬enza A virus, but the test was negative for human influenza subtypes H1N1, H3N2, and H5N1. The CDC subsequently determined that the virus was swine influenza A (H1N1).
The second patient was a 9-year-old girl who lives in Imperial County, California, which is adjacent to San Diego County. She had a cough and fever, was treated with amoxicillin/clavulanate potassium and an antihistamine, and made a full recovery.
"Two is a very small sample size, but I think it is unlikely that this swine flu is associated with severe flu symptoms," Stephen Munday, MD, MPH, the public health officer for Imperial County, told Medscape Infectious Diseases. "Both of these cases would have completely recovered without medical intervention, and at least so far, there seems to be no propensity for severe influenza."
Dr. Munday added that of the 50 severe cases of pediatric influenza in California this flu season that would have been thoroughly evaluated because of their severity, no cases of swine influenza were detected.
"Other cases of swine flu may have occurred but remained undetected because they were mild and/or were not evaluated," he said and added that several close contacts of the patients with influenza-like symptoms are currently being evaluated to determine any relationship with the case patient viruses.
Need for Influenza Surveillance
These cases highlight the need for proper testing for suspected influenza virus, "not just in California, but around the country," Dr. Munday said.
The MMWR report advises clinicians who suspect swine influenza virus infection in humans to obtain a "nasopharyngeal swab from the patient, place the swab in a viral transport medium, and contact their state or local health department to facilitate transport and timely diagnosis at a state public health laboratory."
The CDC also requests that state public health laboratories send all influenza A specimens that cannot be subtyped to the CDC, Influenza Division, Virus Surveillance and Diagnostics Branch Laboratory.
Swine Flu on the Rise
According to the editorial note in the MMWR report, a total of 14 cases of swine influenza in humans, including the 2 current cases, have been reported since December 2005. This number represents an increase compared with previous years. This may be partly a result of an increase in influenza testing capabilities in public health labo¬ratories, although "genetic changes in swine influenza viruses and other factors also might be a factor," the authors note.
"The lack of known exposure to pigs in the two cases described in this report increases the possibility that human-to-human transmission of this new influenza virus has occurred," they add.
According to the CDC's Tom Skinner, with the increased level of influenza surveillance now taking place in Southern California, "it would not be a surprise to detect more suspected cases that warrant further investigation. As the CDC learns more about these cases we will update information regarding these cases," he said.
Morb Mortal Wkly Rep. Published online April 21, 2009.

http://www.medscape.com/viewarticle/701738

[HenryN]

Local Child Infected With Rare Swine Flu

April 21, 2009 Two cases of human infection with swine influenza A (H1N1) have been detected in Imperial and San Diego Counties, according to the Imperial County Public Health Department and San Diego County Health & Human Services Agency. In Imperial County, the case is a 9-year-old while the case in San Diego County is a 10-year-old. Confirmation for the San Diego case was received from the Centers for Disease Control and Prevention (CDC) on April 15th and Imperial County received confirmation on April 17th. Neither of the patients were hospitalized and both have recovered. Although swine influenza viruses normally infect and cause illness in pigs, sporadic human infections with swine flu do occasionally occur. Both the Imperial County Public Health Department and San Diego County Health & Human Services Agency are working closely with state and federal officials on the investigation. Preliminary study of the virus indicates that this particular genetic combination of swine influenza is novel and has not been seen before in the United States. Neither of the two patients reported being near pigs and both cases were detected through seasonal influenza surveillance with local providers. Health officials in both counties are investigating the source and transmission of the two infections by speaking with family members and others who had close contact with the cases. The first human swine influenza virus, H1N1, was reported in the United States in 1930. Swine flu is a cause of respiratory disease in pigs throughout the world and can occasionally cause human disease. In the past, CDC received reports of approximately one human swine influenza virus infection every one to two years in the United States, but since 2005, 12 cases of human infection with swine influenza have been reported. The increase could be a result of increased influenza testing capabilities and capacities in public health laboratories. Most commonly, human cases of swine influenza happen when people are in close proximity to infected pigs, such as in pig production barns and livestock exhibits at fairs. The symptoms of swine influenza in people are similar to the symptoms of regular seasonal influenza infection and include fever, lethargy, coughing and lack of appetite. To diagnose swine influenza A infection, a respiratory specimen is collected within the first 4 to 5 days of infection. The seasonal influenza vaccine (i.e., flu shot) does not protect against swine H1N1 viruses. Although the current influenza season has been mild in both counties, individuals are encouraged to take the following steps to stop the spread of influenza and other respiratory illnesses: · Stay home when you are sick to avoid spreading illness to friends and co-workers or students. · Cough or sneeze into your elbow or a tissue and properly dispose of used tissues. · Wash your hands thoroughly with soap and warm water or use an alcohol-based hand sanitizer to get rid of most germs and avoid touching your eyes, nose and mouth. · Stay healthy by eating a balanced diet, drinking plenty of water and getting adequate rest and exercise. For further information about swine influenza, visit the CDC Web site. http://www.sdcounty.ca.gov/Portal/Ne...9swineflu.html

[HenryN]

For Immediate Release: Tuesday April 21, 2009
Two Individuals in Imperial and San Diego Counties have
Been Confirmed with Swine Flu
An investigation is being conducted with State and Federal officials.
IMPERIAL / SAN DIEGO COUNTIES – The Imperial County Public Health Department
and San Diego County Health & Human Services Agency announced today that two cases of
human infection with swine influenza A (H1N1) have been detected in Imperial and San Diego
Counties. In Imperial County the human case is a nine-year old while the case in San Diego
County is a 10-year-old. Confirmation for the San Diego case was received from the Centers
for Disease Control and Prevention (CDC) on April 14th and Imperial County received
confirmation on April 17th. Neither of the patients were hospitalized and both have recovered.
Although swine influenza viruses normally infect and cause illness in pigs, sporadic human
infections with swine flu do occasionally occur. Both the Imperial County Public Health
Department and San Diego County Health & Human Services Agency are working very closely
with state and federal officials on the case investigation.
Preliminary study of the virus indicates that this particular genetic combination of swine
influenza is novel and has not been seen before in the United States. Neither of the two
patients reported being near pigs and both cases were detected through seasonal influenza
surveillance with local providers. Health officials in both counties are investigating the source
and transmission of the two infections by speaking with family members and others
that had close contact with the cases.
The first swine influenza virus, H1N1, was reported in the United States in 1930. Swine flu
-- more --
is a cause of respiratory disease in pigs throughout the world and can occasionally cause human disease. In the past, CDC received reports of approximately one human swine influenza virus infection every one to two years in the United States, but since 2005, 12 cases of human infection with swine influenza have been reported. The increase could be a result of increased influenza testing capabilities and capacities in public health laboratories.
Most commonly, human cases of swine influenza happen when people are in close proximity to infected pigs, such as in pig production barns and livestock exhibits at fairs. The symptoms of swine influenza in people are similar to the symptoms of regular seasonal influenza infection and include fever, lethargy, coughing and lack of appetite. To diagnose swine influenza A infection, a respiratory specimen is collected within the first 4 to 5 days of infection. The seasonal influenza vaccine (i.e., flu shot) does not protect against swine H1N1 viruses. Although the current influenza season has been mild in both counties, individuals are encouraged to take the following steps to stop the spread of influenza and other respiratory illnesses: Stay home when you are sick to avoid spreading illness to co-workers and friends. Children with flu-like symptoms should stay home to avoid spreading illness to classmates and staff. Cough or sneeze into your elbow or a tissue and properly dispose of used tissues. Wash your hands thoroughly with soap and warm water or use an alcohol-based hand sanitizer to get rid of most germs and avoid touching your eyes, nose and mouth. Stay healthy by eating a balanced diet, drinking plenty of water and getting adequate rest and exercise.
For further information about swine influenza, visit www.cdc.gov/flu/swine/index.htm.
If you are a member of the media seeking further information, please contact any of the following contacts: Imperial County Public Health Department, Public Health Information Officer
(760) 482-4461; mariapeinado@co.imperial.ca.us
San Diego County Health & Human Services Agency, Media and Public Relations Specialist: (619) 515-6535; thomas.christensen@sdcounty.ca.gov

http://www.icphd.org/menu_file/Human...009.pdf?u_id=1

[ironorehopper]

[From ProMedMail.org, commentary by moderator dr Craig Pringle. msIOH]

(...)

[Infection with swine influenza virus has been detected sporadically in humans since the 1950s and the human disease is usually clinically similar to disease caused by infections with human influenza viruses. However, complications that include pneumonia and death have occasionally been reported in the literature in otherwise healthy adults without underlying
disease. On the whole, human infections with swine influenza virus, to date, have been different and much milder than those seen with avian influenza A (H5N1) and more similar to infections with low pathogenic avian influenza viruses (see Eurosurveillance edition 2009; 14(7) at <http://www.eurosurveillance.org/View...rticleId=19124>).

The significant features of this report are that although this is not a new subtype of influenza A in humans, concerns exist that this new strain of swine influenza A (H1N1) is substantially different from human influenza A (H1N1) viruses, that a large proportion of the population might be susceptible to infection, and that the seasonal influenza vaccine H1N1 strain might not provide protection. The lack of known exposure to pigs in the 2 cases increases the possibility that human-to-human transmission of this new influenza virus has occurred.

The viruses isolated from the 2 children are similar and carry a unique combination of genes not previously encountered. No information currently is available regarding the efficiency of their transmission in swine or in humans - Mod.CP

San Diego and Imperial are the southernmost counties in California and can be located on the map at <http://www.californiacountymaps.com/>. The state of California can be seen on the HealthMap/ProMED-mail interactive map at <http://healthmap.org/r/009X>. - CopyEd.MJ]
(...)
-
[Full text: http://apex.oracle.com/pls/otn/f?p=2..._ID:1000,77148 ]
-----

[HenryN]

Commentary

[HenryN]

I talked to public health in Imperial Valley. Additional suspect cases (unrelated to confirmined case) are being tested and results are expected by noon tomorrow.

This raises questions on travel of San Diego cluster to Imperial (Valley).

[HenryN]

Updated map

http://maps.google.com/maps/ms?ie=UT...11,3.99353&z=8

[AlaskaDenise]

Originally Posted by niman

Commentary

Commentary

Silent Human Spread of Swine H1N1 in Southern California

Recombinomics Commentary 20:42
April 22, 2009

The viruses isolated from the 2 children are similar and carry a unique combination of genes not previously encountered. No information currently is available regarding the efficiency of their transmission in swine or in humans - Mod.CP

The above ProMED comments on the two swine flu isolates from children in southern California may be accurate for transmission in swine, but the symptomatic family members described in the MMWR dispatch provides information that transmission in humans is efficient, which is also supported by the fact that these two clusters are 100 miles apart (see updated map).

The family members had even milder courses than the two confirmed cases, so no samples were collected and the spread was both efficient and silent. There is no indication that the four symptomatic family members sought treatment, and in most instances medical assistance would have just led to an influenza A diagnosis and treatment.

The two cases were identified because they were linked to surveillance program that sero-typed the virus. The sero-typing failure led to further testing which identified the H1N1 serotype as swine. A more routine visit would have just determined that the patient had influenza A.

The lack of any connection between the two confirmed cases, other than age (9F and 10M) and location in southern California suggests that there are many undetected cases in the area, which likely includes Mexico, where some contacts were located. Therefore, an international survey would gain additional information on the spread of the H1N1.

These two clusters differ from prior swine detections because the two outbreaks are separated by a large distance and involve the same virus with the unusual constellation of swine flu genes that has not previously been reported in swine.

The CDC has promptly released the HA (EPI176470), NA(EPI176472), and M(EPI176471) gene sequences of A/California/04/2009 from 10M (at GISAID). These sequences confirm that the NA and M gene have a Eurasian swine origin, while the HA sequences is North American swine. The presence of S31N in the M gene, which is common in European swine, confers resistance to amantadine and rimantadine. Release of the sequences from the other isolate would be useful to determine how long these viruses have been in human populations.

The efficient transmission of swine H1N1 in a human population raises concerns of further evolution and adaptation through the exchange of genetic information with human seasonal flu via reassortment and recombination (including H274Y).

Recombination between swine H1N1 and seasonal H1N1 generated the 1918 pandemic strain, which is cause for concern.

.

[Shiloh]

Source: http://www.google.com/hostednews/can...-85kj2dwDUoYsg

Swine flu cases 'deja vu all over again' for scientist who studied 1976 outbreak

TORONTO — News that public health authorities are investigating human cases of swine flu was, to borrow from a phrase from the inimitable Yogi Berra, like deja vu all over again for Dr. Harvey Fineberg.

Fineberg is one of two academics commissioned by the U.S. government to investigate what became known as "the Swine Flu Affair" of 1976 - the premature pulling of the trigger in the U.S. government's response to the discovery of a cluster of human cases of swine flu among soldiers at Fort Dix in New Jersey.

"It is sort of eerily reminiscent," Fineberg, now president of the U.S. Institute of Medicine, says of hearing that the Centers for Disease Control and California public health officials are investigating human infections with swine flu viruses in two unrelated children who had had no contact with each other or with pigs.

Others involved in the 1976 episode share the sense that history is being replayed before their eyes.

"In fact, I got exactly that email from Dave Sencer - just this morning he said: 'Deja vu all over again,"' says Dr. Walter Dowdle.

Dowdle, retired from the CDC and now with the Atlanta-based non-profit Task Force for Global Health, was the agency's chief of virology during the swine flu incident. Sencer - Dr. David Sencer - was head of the CDC at the time. He was fired in the fallout from the episode.

Both men were in the thick of the response to what was thought to be the start of a flu pandemic with a virus feared to be similar to the 1918 Spanish flu, which killed upwards of 50 million people worldwide.

This time, authorities are being cautious in interpreting the significance of the swine flu cases, saying much more investigation is needed to see if more people have been sick, if some are still falling ill and whether the virus - a swine version of the H1N1 subtype - poses a threat to the population at large or only selected age groups such as children.

"While we have a low index of suspicion that this is a pandemic, we're being very careful in our investigation to rule out every possibility," Dr. Lyn Finelli, of the CDC's influenza division, explained when revealing the existence of the cases on Tuesday.

The caution likely stems from lessons learned from the 1976 response to a pandemic that didn't materialize.

Early that year an explosive outbreak of a respiratory illness swept through recruits at Fort Dix. While samples taken from sick soldiers were being tested, one man died of his illness.

In mid-February, it was discovered several of the men had been infected with swine influenza viruses - viruses similar to that responsible for the 1918 Spanish flu pandemic.

U.S. officials ordered the manufacture of swine flu virus vaccine and the country proceeded to launch a mass immunization program that saw upwards of 40 million people injected with the vaccine.

The feared pandemic never occurred. But the vaccine appeared to trigger a high level of cases of Guillain-Barre syndrome, a type of paralysis that is often, though not always, time limited. The immunization program was scrapped and thousands or recipients filed injury claims.

Fineberg and Richard Neustadt wrote "The Swine Flu Affair: Decision-Making on a Slippery Disease" at the request of then secretary of health Joseph Califano. Looking back on the event, Fineberg says it offers clear lessons on what not to do for officials leading today's investigation.

"One of the big lessons from the last experience that I think does apply is to be careful not to decide more than you need to decide at any particular time," he said in an interview from Washington.

"So the investigation in an intensive way is critical. But you don't start out by declaring or deciding that you're going to embark on whatever immunization or protection program or something at this stage."

Still, Fineberg thinks the swine flu episode may be a double-edged sword in the current context.

"The experience of the swine flu episode itself could be a handicap because it could lead in a way to misplaced expectations that this will be just like the last one," he says.

"And we don't know enough scientifically to be able to say that with confidence."

Dowdle also served as head of the World Health Organization collaborating centre for influenza at the CDC while he was with the agency, so he has had a lot of experience with the famously unpredictable virus.

He says if the swine virus responsible for the California cases continues to spread among people, "I think that would be a new chapter in influenza and we have to see what happens."

"Nothing's surprising with flu. Nothing at all." Dowdle say.

[alert]

The Oaxaca case(s) could now be swine flu. Mexico has been reporting severe even fatal respiratory illnesses in Oaxaca nd Mexico City and elsewhere for over a month. I actually hope this is a H1N1 swine flu pandemic, as we have drugs from flu, and H1N1 is at least kind of similar to other circulating flu. The CFR for this one wouldn't be too bad relatively speaking (lower than an H5N1 pandemic, or a SARS pandemic, or something novel).

[HenryN]

CDC: Swine flu seen in 2 California children

• Story Highlights
• Rare swine flu diagnosed in 2 kids near San Diego, California, CDC reports
• In U.S., an average one person gets the disease every two years
• Infected kids have had no known contact with swine, each other
• Both kids recovered on their own

By Theresa Tamkins






The Centers for Disease Control and Prevention is investigating two cases of swine flu detected in children in the San Diego, California, area last week.

Swine flu is usually diagnosed only in pigs or people in regular contact with them.


Swine flu is caused by a virus similar to the regular flu virus that circulates in people every year, but is a strain that is typically found only in pigs or in people who have direct contact with pigs.
The children were infected with a virus known as swine influenza A H1N1, which has a unique combination of genes not previously seen in flu viruses in either humans or swine - although it shares similarities with a virus that has been circulating in pigs since 1999.
Typically one person in the United States is infected with swine flu every one to two years, although there have been 12 cases in the three-year period between December 2005 and January 2009. Most of the time, people who get sick from swine flu have been in contact with pigs, and the virus doesn't spread from person to person.
Since neither of the two children, a 10-year-old boy and a 9-year-old girl, had contact with pigs, it "increases the possibility that human-to-human transmission of this new influenza virus has occurred," according to a CDC report. The girl did attend an agricultural fair four weeks before becoming sick, she said, but did not have any contact with pigs or other livestock. Family members of both children also had flu-like symptoms, but it's not clear whether they were infected with the same virus since samples weren't taken when they were ill.
Both children had a fever and cough in late March, and one child vomited. The children, who live in the adjacent San Diego and Imperial counties in Southern California but had no known contact with one another, have since recovered.
"We've only got the two cases to go on and both kids recovered on their own, so that's certainly good news," says Tom Skinner, a CDC spokesman.
The boy did travel from California to Dallas, Texas, on a trip to visit family members and the CDC is reaching out to crew members on that flight to see whether any other people experienced flu-like symptoms, says Skinner.
"He was probably at the tail end of his illness, but yes, he was symptomatic," he says. "We're just reaching out to crew members at this point. Based on what we learn from that initial outreach, if we feel like we need to reach out to other passengers on the plane, we will."
Health Library

• MayoClinic.com: Health A-Z

These types of investigations are designed to "get a better handle on just how transmissible this virus might be," says Skinner. "When we see the introduction of a new flu virus from animal into humans that's one of things we're interested in: understanding how efficiently is the virus transmitted and how sustainable is the virus transmission from person to person."
The virus seems to be resistant to treatment with the antiviral drugs amantadine and rimantadine. It's not clear yet whether the virus is resistant to other drugs, such as oseltamivir and zanamivir.
Skinner says "we're still early in the course of learning about it, but as far as the general public goes there's nothing they need to be doing differently today than what they were doing yesterday when it comes to their knowledge and behavior about preventing flu."
The most famous outbreak of swine flu in the United States occurred in 1976 in recruits at Fort Dix, New Jersey. The cases triggered fear of a pandemic - largely because the lethal 1918 flu pandemic was thought at the time to be a result of a swine flu mutation - that resulted in more than 40 million people being vaccinated. The program was later criticized when a swine flu pandemic did not materialize and a number of cases of vaccine-related side effects were reported

[Shiloh]

Source: http://www.cidrap.umn.edu/cidrap/con...2209swine.html


Swine flu cases recall 1976 episode

Robert Roos and Lisa Schnirring * Staff Writers

Apr 22, 2009 (CIDRAP News) – Swine influenza viruses have never been documented as the cause of a human influenza pandemic, but in 1976 they generated pandemic fears strong enough to trigger a nationwide vaccination campaign.

The reporting of swine flu cases in two California children this week stirred memories of the 1976 episode, which caused major embarrassment for public health authorities when the pandemic never materialized.

The Centers for Disease Control and Prevention (CDC) announced yesterday that two children in southern California fell ill in late March with what turned out to be swine flu infections. Both of the children recovered, and neither was hospitalized.

But the cases raised concern because neither child had any known exposure to pigs, suggesting that human-to-human transmission might have occurred. Further, the virus was found to be a new strain of swine influenza A/H1N1 that differs substantially from human H1N1 strains. That suggested that much of the population could be susceptible to it and that the H1N1 antigen in seasonal flu vaccines probably would not protect people, the CDC said.

CDC and California officials offered little new information on the cases and investigation today. Officials are testing contacts of the two children, including four family members who also were recently sick, to see if they have antibodies indicating they were infected with the H1N1 virus. CDC spokesman Tom Skinner said it would be several days or possibly weeks before the results are available.

Human swine flu infections are rare but have become slightly more frequent in recent years, with 14 cases (including the two in California) since December 2005, according to the CDC. Almost always the infection has been associated with exposure to pigs, which are very commonly infected. Ken August, a spokesman for the California Department of Public Health, said today that until the two latest cases, no human cases of swine flu had been identified in California in several years.

Very rarely have people with swine flu infections been known to pass the infection to someone else. One such case occurred in Wisconsin in 1988, when a pregnant woman fell ill after visiting a swine exhibition, according to a CDC question-and-answer article on swine flu. She was hospitalized with pneumonia and died 8 days later. Follow-up studies suggested that "one to three" healthcare workers who had contact with her had mild flu-like illnesses and antibody evidence of swine flu infection.

Far better known is the swine flu episode of 1976. About 200 soldiers in basic training at Fort Dix in New Jersey fell ill in Jnauary and February, according to a 2006 article by Richard Krause, who was director of the National Institute of Allergy and Infectious Diseases at the time. At least four soldiers had pneumonia, and one died, according to the CDC article.

The virus was identified as an H1N1 swine flu virus, "thought to be a direct descendant of the virus that caused the pandemic of 1918," wrote Krause. "This conclusion was based on antibodies to H1N1 antigens found in survivors of the 1918 pandemic and the belief that the 1918 virus was eventually transmitted to pigs in the Midwest, where it persisted and caused sporadic human cases."

Public health experts, fearing a possible replay of the 1918 pandemic, engaged in an intense debate about how to respond. Eventually they launched a nationwide vaccination campaign, which was announced by President Gerald ford in March. By the end of the year, 48 million people had been vaccinated, according to an account in Arthur Allen's book Vaccine: The Controversial Story of Medicine's Greatest Lifesaver.

But the feared pandemic never materialized. "The virus is thought to have circulated for a month and disappeared," the CDC article says. "The Fort Dix outbreak may have been an animal anomaly caused by introduction of an animal virus into a stressed human population in close contact in crowded facilities during the winter."

Not only did the pandemic fail to appear, but the vaccine apparently harmed some people. Health officials suspended the vaccination campaign on Dec 16, 1976, after receiving numerous reports of Guillian-Barre syndrome (GBS), a paralyzing neurologic illness, after vaccination, according to an August 1979 report in the American Journal of Epidemiology. Nationwide surveillance detected 1,098 patients with GBS onset from October 1976 through January 1977. Epidemiologic evidence suggested that many cases were related to vaccination, with an estimated risk of 1 case for every 100,000 vaccinations.

Studies of influenza vaccines used after 1976 showed no increased risk for GBS in adults except for borderline statistically significant increases in the 1992-93 and 1993-94 flu seasons, according a report in the Jul 15, 2008, issue of Journal of Infectious Diseases. However, experts still don't know what caused the GBS cases after the swine flu vaccination. One theory was that bacterial antigens from contaminated eggs used in vaccine production could have elicited GBS.

In any case, the episode left the public health establishment demoralized. "The debacle opened public health authorities to the kind of criticism and even ridicule that they had never had to countenance before," wrote Allen.

The concern stirred by this week's report of the two swine flu cases in California readily recalled the 1976 episode. But Marie Gramer, DVM, PhD, a University of Minnesota veterinarian who has studied swine flu, cautioned against drawing many parallels as yet.

"It's kind of too early for that," she said. "Certainly in 1976 what got people riled up was that it was adults getting sick. That was outside the norm. This [the California cases] affected children, and children get a lot of influenza."

She said she personally is not overly concerned about the latest cases. "But I think it's important to get this information out there and that people be aware that flu can be shared between humans and pigs," she added.

While influenza is notoriously unpredictable, there is no firm evidence of a swine flu virus having triggered a human flu pandemic, according to multiple reports. The virus that swept around the world in 1918 is believed to have been an avian strain that somehow adapted to humans. The two pandemics since then, in 1957-58 and 1968-69, resulted from genetic reassortment of avian and human strains, though the reassortment could have occurred in an intermediate host such as pigs. No good evidence is available for the many pandemics before 1918.

If by any chance the virus in the California proves capable of spreading from person to person, the existing seasonal flu vaccine will not be likely to protect people, even though the vaccine contains an H1N1 component, according to the CDC. "The H1N1 swine flu viruses are antigenically very different from human H1N1 viruses," the CDC article states.

Most of the flu viruses recently found in pigs have been H1N1 and H3N2 strains, the CDC says. Current swine flu H3N2 viruses are closely related to human H3N2 viruses, because they were introduced into pigs from humans in the late 1990s. But H1N1 swine viruses have been known to circulate in pigs at least since the 1930s.

The seasonal flu vaccine also includes an H3N2 component. Since the human and swine H3N2 strains are closely related, "the seasonal influenza vaccine will likely help provide partial protection against swine H3N2, but not swine H1N1 viruses," according to the CDC.

See also:

CDC questions and answers about swine flu
http://www.cdc.gov/flu/swine/key_facts.htm

Richard Krause EID article on the 1976 swine flu episode
http://www.cdc.gov/ncidod/EID/vol12no01/05-1132.htm

Aug 1979 Am J Epidemiol study abstract

Jul 15, 2008, J Infect Dis study abstract
http://www.journals.uchicago.edu/doi/abs/10.1086/589624

CDC guidance on infection control and antiviral treatment for patients with suspected swine flu infections
http://www.cdc.gov/flu/swine/recommendations.htm

[HenryN]

Video from Imperial County outbreak

http://www.kswt.com/Global/category....av=menu613_2_3

(which is likely just across the border from Mexicali)

[gsgs]

latest H1N1 swine-flu genome from USA which I have is
A/swine/Ohio/24366/2007(H1N1)
with 1,4,5,6,7,8 from 1918 and
2 from Alb.-teal/92 , 3 from Canadian swine

I'm updating...

---------edit----------
OK, I have it now.
All public American swine H1N1 since 2005 seem to be similar to that Ohio virus above
with new segments 2,3 and the rest from <1918

--------edit--------
segment 1 is also avian and not from <1918

so

----------------
http://www.pubmedcentral.nih.gov/art...?artid=2603093
http://www.newfluwiki2.com/diary/2018/


----------------

so the 8 segments are since 10,40,10,95,30,30,95,95 years in mammals

[HenryN]

Unrelated cases of swine flu in Calif. children have U.S. officials on alert

Provided by: Canadian Press
Written by: Helen Branswell, Medical Reporter, THE CANADIAN PRESS
Apr. 21, 2009

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.
Discovery of the two cases, in children who apparently had no contact with pigs or with each other, suggests there probably has been some person-to-person spread of swine flu viruses, officials of the U.S. Centers for Disease Control said Tuesday.
Whether the viruses continue to spread isn't currently known.
"The investigation is not finished. It's ongoing. But of course not having that direct swine link does raise additional questions and does suggest that there may have been human-to-human transmission. And so it basically ratchets it (concern) up a bit," said Dr. Nancy Cox, head of the CDC's influenza division.

"I think this is one of those situations where everyone will want to stay tuned." U.S. officials notified the World Health Organization of the cases last Friday, as required under the International Health Regulations. That treaty stipulates that countries must notify the WHO when they see cases of infectious diseases that pose an international threat, such as novel subtypes of influenza with pandemic potential.
Dr. Keiji Fukuda, a senior official of the WHO, said there is no need at this point to raise the global pandemic alert level.
The world is currently in phase 3 of a six phase alert scale because of ongoing sporadic cases of H5N1 avian influenza. Phase 3 means there are occasional human cases of influenza with a subtype with pandemic potential, but that there is no ongoing transmission.
"All things considered, based on what we already know about H1 (swine) infections and that they occur, I'm pretty comfortable that the right steps are being taken," said Fukuda, an influenza expert who is the WHO's acting assistant director general for health security and the environment.
Canada became aware of the situation when WHO was notified, said Dr. Arlene King, director general of the Public Health Agency of Canada's centre for immunization and respiratory infectious diseases.
King said no cases of infection with this particular swine flu virus have been spotted in Canada, but the public health network across the country has been put on the lookout.
"The labs are on alert and have been asked to send any non-subtypable influenza viruses ... to the National Microbiology Laboratory for testing and review," King said, adding they have also been asked to report if they can't identify a pathogen found in samples taken from a patient with flu-like symptoms, or have surveillance information indicating unexpected increases in illness.
The cases involved a boy, 10, from San Diego County and a nine-year-old girl from Imperial County, both of whom have recovered from their illnesses.
The two, who live over 150 kilometres apart, became ill at the end of March and sought care from clinics involved in an influenza surveillance program. Those clinics tested for flu; when they found viruses that didn't match known human viruses, they alerted authorities.
Given that most people with flu aren't tested, the CDC's Dr. Lyn Finella called the discovery of the swine flu infections "a very fortunate lightning strike."
Human infections with swine flu viruses are not unprecedented. A scientific paper published in 2007 recorded 50 known cases of human swine flu infections, in the U.S., Canada, the Netherlands and several other countries.
And most famously, a cluster of swine flu cases at Fort Dix, N.J., in 1976 triggered concerns a pandemic might be emerging. Vaccine was made and 47 million people were vaccinated against a pandemic that did not materialize.
Canada sees about one human case of swine flu a year, King said. And the CDC officials said until a couple of years ago, the U.S. averaged one case every year or two. But since December 2005, there have been 14 cases, including these children.
In most of the recent cases, direct exposure to pigs could be established. And when cases were caused by H1N1 viruses, those viruses were relatively closely related. Not so in the viruses responsible for the infection in these children.
The viruses, which were described as very similar to one another, have unusual properties never seen before in swine flu viruses, the CDC said.
Two of the genes of the viruses were from swine viruses that normally circulate in Eurasia, a finding that has added to the level of interest and concern. And the hemagglutinin - the H in a flu virus's name - has a lot of mutations when compared to other swine H1N1 viruses, Cox said.
"It's different enough so that we're going to be looking very carefully at properties like receptor binding properties, growth kinetics. We'll be doing some animal model experiments and so on," she noted.
In California, health officials are investigating with help from the CDC, checking the children's contacts and looking for others who may have also been infected.
The CDC said in both cases, two family members were also sick around the time of the confirmed infections, but none of those four people was tested at the time for influenza.
Blood samples have been taken from those four and other people who have been in contact with the children; the blood samples will be tested for antibodies to these swine flu viruses, though results may not be available for some time, Finelli said.
The investigation has also spread to Texas, because the 10-year-old boy travelled by plane on April 3, while he was still ill. He and a brother who travelled with him remain in Texas, the CDC said.
Experts say it is not clear whether a swine flu virus of the H1N1 subtype could trigger a human pandemic at this point in time.
Human H1N1 viruses have been circulating around the world for decades, so there is a lot of immunity to those viruses in the population. But it's not yet known how much protection previous exposure to human H1N1 viruses - or to vaccine made to protect against them - would offer against these novel swine viruses.
"I think that the 100 per cent accurate answer is that nobody knows," Fukuda said from Geneva.
"But I think the other part of that answer is that if there's great enough antigenic distance between the current circulating H1 (human) viruses and for example a swine H1 virus, then there's no reason why it wouldn't behave in a pandemic fashion."
The term "antigenic distance" means how closely related viruses are to each other from the point of view of whether antibodies to one offer cross protection to another. If viruses are antigenically similar, there should be good cross protection.
But if there is great antigenic distance between human H1N1s and these swine flu viruses, the swine viruses would have greater potential to cause human illness.
Cox said that the CDC will be testing blood samples from people of a variety of age groups to try to get a sense of how much of the population might be vulnerable to these viruses. That work, which will take some time, should give a clearer picture of how much of a threat the viruses might pose if they are still circulating.



http://chealth.canoe.ca/channel_heal...hannel_id=1020

[ironorehopper]

ECDC Health Content: Swine Influenza A(H1N1) Infection in Two Children in Southern California, March-April 2009.

Swine Influenza A(H1N1) Infection in Two Children in Southern California, March-April 2009


On April 17th, 2009, the US Centers for Disease Control and Prevention (CDC) reported that two cases of febrile respiratory illness occurring in children who resided in adjacent counties in Southern California were caused by infection with a novel swine influenza A (H1N1) virus.


CDC reported on its Morbidity and Mortality Weekly Report (MMWR) that the viruses from the two cases are closely related genetically, likely to be resistant to amantadine and rimantadine (but probably sensitive to oseltamivir and zanamivir) and contained a unique genetic combination not previously reported among swine or human influenza viruses in US or elsewhere. Neither child had history of contact with pigs and the source of infection is not known.

Intensive epidemiological and virological investigations are ongoing around the cases.

This new strain of swine influenza A(H1N1) virus is substantially different from currently circulating human influenza A(H1N1) viruses. Hence CDC points out that much of the population would be susceptible to infection and that the seasonal influenza vaccine H1N1 strain would not provide protection should the infection start to transmit efficiently.

The history of the cases is that CDC was notified on April 13th of a 10 year-old boy from San Diego County, California who had developed fever, cough and vomiting on March 30th, 2009. A nasopharyngeal swab was collected in an outpatient clinic, symptomatic treatment was given and all symptoms resolved within a week. The child had not received influenza vaccine during this season. Initial testing identified an influenza virus type A, but that was negative for human influenza subtypes H1N1 and H3N2 and hence the sample was considered unsubtypable influenza A.

The WHO Collaborating Centre at CDC received clinical specimens and determined that the virus was a swine influenza of type A(H1N1). No exposure to pigs was reported and though the mother and brother of the case had respiratory illness episodes a few weeks before the case no specimens had been collected from them.

The second case, took place at about the same time but 200 km away in a 9 year-old girl in Imperial County, California, which is adjoins San Diego county. On March 28th, 2009, she developed cough and fever and was taken to an outpatient facility that was participating in an influenza surveillance project. She had not been immunised and was treated with antibiotics and symptomatically and she also recovered uneventfully. Again neither the case nor her family had had recent exposure to pigs. A brother and a cousin of the case had episodes of respiratory illness sometime before the case but no samples were submitted for testing.

CDC reports intensive investigations (enhanced surveillance) are underway but as of April 21st no link between the two cases has been identified, and no additional cases have been reported


ECDC comment (09-04-22):

The infection of humans with a novel influenza A virus infection of animal origins as has happened here is of concern because of the risk, albeit small, that this could represent the appearance of viruses with pandemic potential. That is an Influenza A viruses able to infect humans, cause significant disease and spread efficiently from human to humans. These two cases just about meet the first two criteria, though it is noticeable that both the children’s illnesses were mild and essentially self-limiting, neither required specific therapy or hospitalisation. Indeed the viruses only came to light because the children were taken to clinics taking part in a clinical study and a surveillance exercise.(1)

There are therefore some similarities with the 2008 case in an adult pig handler reported earlier this year from Spain that was also mild and only were detected through a sample being taken for surveillance.(2, 3)

However there are also important differences in the American child cases, namely that in neither case was there any history of recent contact with pigs, the cases were broadly in the same locality, adjoining countries in California (though they live 200km apart) and the viruses were novel ones, not previously seen in the USA.(1)

There is a steady trickle of human infections with swine influenza in the United States. The US CDC in their Editorial Comment on the cases describes how even without a formal surveillance system the USA generally sees one or two human infections with Swine Flu every year, with around 12 known cases in the 3 calendar years 2006 to end 2008.

However almost all of these cases had some kind of direct or indirect link with pigs, which these cases do not.(1) This makes the possibility of limited human to human transmission of swine flu much more likely.

What is essential now is to answer questions over the extent of human infections around the cases and the potential for spread?

It is too early to answer those questions but it is reassuring that international reporting has been rapid, there vigorous case finding is underway and that apart from some history of possible upper respiratory infections there is no indication of sustained human-to-human transmission or widespread infection of contacts of the two ill patients.(1)

Further information will be eagerly awaited from the US. If as seems likely the appearance of these cases are explained by an element of chance entry into clinical studies or surveillance systems with such intense activity it is quite likely that more isolated cases counl emerge.

However it seems highly unlikely that these two cases represent the emergence of a pandemic strain.

As was noted in the earlier editorial in Eurosurveillance and by the US CDC not much is known about the circulation of swine influenza in animals and considerably less about their infections of humans.(1,3-7)

Infection in pigs is regarded as especially problematic because of the risk of “reassortment” to produce a novel virus, even a pandemic strain either in the pig “mixing vessel” or in a human dually infected with a human and pig strain. Triple recombinant swine influenza viruses with avian, human and swine genes have been seen in the United States and these have then transmitted to humans.(8,9)

The actual risk can only become clear if epidemiological investigations are combined with experimental research as is now being done in the USA and it’s the case that because of the relative lack of surveillance in Europe its not clear how to interpret there being no reports of triple recombinants.

There is also a challenge to Europe in having a need for centralised systems for being able to rapidly upgrade influenza reference diagnostic systems in Europe to cope with new viruses such as these.

So in conclusion these mild US cases infected with a novel influenza are not reflecting the emergence of a pandemic strain but they at least raise the possibility that there has been limited human to human transmission.


The enhanced surveillance may result in more isolated mild human infections being detected and reported as a consequence. If this happens it should not be misinterpreted as a change in that conclusion.

Finally this does highlight another area where closer and coordinated human and animal surveillance in Europe is needed around a poorly understood zoonosis.


References:

1. CDC Swine Influenza A (H1N1) Infection in Two Children --- Southern California, March--April 2009 MMWR April 21 2009 / 58 (Dispatch); 1-3.
2. Adiego Sancho B, Omeñaca Terés M, S Martínez Cuenca S et al Human case of swine influenza A (H1N1), Aragon, Spain, November 2008 Eurosurveillance 2009 14, Issue 7, 19 February
3. Van Reeth K, Nicoll A, A human case of swine influenza virus infection in Europe – implications for human health and research Eurosurveillance 2009 14, Issue 7, 19 February
4. Olsen CW, Brown I, Easterday BC, Van Reeth K. Swine influenza. In: Straw B.E., Zimmerman J.J., D’ Allaire S., Taylor D.J., eds. Diseases of Swine, 9th edition, Iowa State University Press, Ames, Iowa, 2006: 469-82.
5. Van Reeth K. Avian and swine influenza viruses: our current understanding of the zoonotic risk. Veterinary Research 2007; 38: 243-60.
6. Van Reeth K, Brown IH, Dürrwald R, et al. Seroprevalence of H1N1, H3N2 and H1N2 influenza viruses in pigs in seven European countries in 2002-2003. Influenza and other respiratory viruses 2008; 2: 99-105.
7. Myers KP, Olsen CW, Gray GC. Cases of swine influenza in humans: a review of the literature. Clin Infect Dis. 2007; 44: 1084-
8. 8. Olsen, C.W., et al., Triple reassortant H3N2 influenza A viruses, Canada, 2005. Emerg Infect Dis, 2006. 12(7): p. 1132-5.
9. Newman, A.P., et al., Human case of swine influenza A (H1N1) triple reassortant virus infection, Wisconsin. Emerg Infect Dis, 2008. 14(9): p. 1470-2.
-

ECDC Health Content

[Shiloh]

Source: http://www.google.com/hostednews/ap/...MM_EQD97OCAA80

Swine flu cases up to 7, probe expanding

By MIKE STOBBE –

ATLANTA (AP) — Health officials say a unique type of swine flu has now been diagnosed in seven people in California and Texas, up from the two reported earlier this week. The five new cases in the two states have all recovered, and testing indicates some mainstream antiviral medications work against the virus.

But it's a growing medical mystery: Only a few of the seven people were in contact with each other, and none were in contact with pigs.

U.S. Centers for Disease Control and Prevention officials said Thursday they are expanding their investigation.

[sharon sanders]

CDC Media Briefing Regarding Swine Influenza, A H1N1, Found in People in California and Texas -

3:30 pm EDT Today

Anne Schuchat, M.D. - Acting Interim Deputy Director for Science & Public Health Program (Vaccines)

Nancy Cox, M.D. - Chief, Influenza Division

The CDC held a media conference today regarding the cases of human swine flu in the states of California (San Diego and Imperial Counties) and Texas (San Antonio), USA:

1. There are 7 confirmed cases and is human to human transmission.

2. 5 in California that include a father and daughter.

3. 2 in Texas that include 2 sixteen year old boys that attended the same school.

4. All confirmed cases have recovered.

5. Symptoms include respiratory involvement, diarrhea, and vomiting.

6. Age range is 9 years to 54 years.

7. 3 females, 4 males.

8. This swine influenza has 4 components: North American Swine influenza virus, North American Avian influenza virus, Human influenza virus, Swine influenza virus usually seen in Asia and Europe.

9. CDC does not know the extent of the spread and is continuing investigation. Expects more cases due to scrutiny.

10. Pilot vaccine program has begun, which is standard operating procedure when a new viral strain is discovered.

11. This strain is resistant to amantadine and rimantadine but sensitive to oseltamivir and zanamivir.

12. Swine flu is NOT caused from eating pork.

13. CDC is working with the states involved and Pan American Health Organization, Canada, and Mexico.

14. The CDC does not have any confirmation that the illness that has recently caused several deaths in Mexico is swine influenza.

15. Wash hands, stay home if you are sick. Adopt healthy lifestyle.

16. There will be an update everyday at 3 pm EDT on www.cdc.gov for Swine influenza data.


Sharon Sanders for
FluTrackers.com

[Laidback Al]

Location of the two states with human swine flu infections.

[HenryN]

Commentary

[vinny]

http://www.cidrap.umn.edu/cidrap/con...2209swine.html

[HenryN]

Seven people in U.S. hit by strange new swine flu

Thu Apr 23, 2009 9:54pm BST

*Five new cases found in addition to two people on Tuesday

*CDC says no reason for concern yet

*Flu is unusual mixture but no deaths seen

(Updates throughout with quotes, details)

By Maggie Fox, Health and Science Editor

WASHINGTON, April 23 (Reuters) - Seven people have been diagnosed with a strange and unusual new kind of swine flu in California and Texas, the U.S. Centers for Disease Control and Prevention reported on Thursday.

All seven people have recovered but the virus itself is a never-before-seen mixture of viruses typical among pigs, birds and humans, the CDC said.

"We are likely to find more cases," the CDC's Dr. Anne Schuchat told a telephone briefing. "We don't think this is time for major concern around the country."

The CDC reported the new strain of swine flu on Tuesday in two boys from California's two southernmost counties.

Now, five more cases have been seen -- all found via normal surveillance for seasonal influenza. None of the patients, whose symptoms closely resembled seasonal flu, had any direct contact with pigs.

"We believe at this point that human-to-human spread is occurring," Schuchat said. "That's unusual. We don't know yet how widely it is spreading ... We are also working with international partners to understand what is occurring in other parts of the world."

Two of the new cases were among 16-year-olds at the same school in San Antonio "and there's a father-daughter pair in California," Schuchat said. One of the boys whose cases was reported on Tuesday had flown to Dallas but the CDC has found no links to the other Texas cases.

STRANGE MIXTURE

Unusually, said the CDC's Nancy Cox, the viruses all appear to carry genes from swine flu, avian flu and human flu viruses from North America, Europe and Asia.

"We haven't seen this strain before, but we hadn't been looking as intensively as we have," Schuchat said. "It's very possible that this is something new that hasn't been happening before."

Surveillance for and scrutiny of influenza has been stepped up since 2003, when highly pathogenic H5N1 avian influenza reappeared in Asia. Experts fear this strain, or another strain, could spark a pandemic that could kill millions.

H5N1 currently only rarely infects people but has killed 257 out of 421 infected in 15 countries since 2003, according to the World Health Organization.

The influenza strain is an H1N1, the same family as one of the seasonal flu viruses now circulating. Now that the normal influenza season is waning, it may be easier to spot cases of the new swine flu, Schuchat said.

Only one of the seven cases was sick enough to be hospitalized and all have recovered, Schuchat said.

"This isn't something that a person could detect at home," she said. The new cases appear to have somewhat more vomiting and diarrhea than is usually seen in flu, which mostly causes coughing, fever, sore throat and muscle aches.

The CDC is asking doctors to think about the possibility of swine flu when patients appear with these symptoms, to take a sample and send it to state health officials or the CDC for testing.

Cox said the CDC is already preparing a vaccine against the new strain, just in case. "This is standard operating procedure," Cox said. The agency will issue daily updates here

Seasonal flu kills between 250,000 and 500,000 people globally in an average year. And every few decades, a completely new strain pops up and it can cause a pandemic, a global epidemic that kills many more than usual. (Editing by Eric Walsh)

http://uk.reuters.com/article/latest.../idUKN23355101

[HenryN]

Updated map

http://maps.google.com/maps/ms?ie=UT...,25.488281&z=5

[HenryN]

Commentary

[HenryN]

Human Swine Influenza Investigation

Human cases of swine influenza A (H1N1) virus infection have been identified in San Diego County and Imperial County, California as well as in San Antonio, Texas.

Human Cases of Swine Flu Infection
State	# of laboratory confirmed cases
California	5 cases
Texas	2 cases
Cases will be updated daily at 3 p.m. EST

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 closely with state and local officials in California and Texas and other health and animal officials on investigations into these cases.
CDC has provided the following interim guidance for this investigation.
Residents of California and Texas
Clinicians
State Public Health Laboratories
Public Health/Animal Health
Related Links

Swine Influenza A (H1N1) Infection in Two Children – Southern California, March—April 2009
Morbidity and Mortality Weekly Report (MMWR) April 21, 2009 / Vol. 58 / Dispatch
Interim Guidance on Infection Control and Antiviral Recommendations for Patients with Confirmed or Suspected Swine Influenza A Virus Infection, April 20, 2009
Guidance for health care workers and public health personnel…
Key Facts about Swine Influenza (Swine Flu)
Questions and Answers about swine flu, what it is and how it spreads…
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Residents of California and Texas
CDC has identified human cases of swine influenza A (H1N1) virus infection in people in these areas. CDC is working with local and state health agencies to investigate these cases. We have determined that this virus is contagious and is spreading from human to human. However, at this time, we have not determined how easily the virus spreads between people. As with any infectious disease, we are recommending precautionary measures for people residing in these areas.

• 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.
• Try to avoid close contact with sick 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.
• Avoid touching your eyes, nose or mouth. Germs spread that way.

There is no vaccine available at this time, so it is important for people living in these areas to take steps to prevent spreading the virus to others. If people are ill, they should attempt to stay at home and limit contact with others. Healthy residents living in these areas should take everyday preventive actions.
People who live in these areas who develop an illness with fever and respiratory symptoms, such as cough and runny nose, and possibly other symptoms, such as body aches, nausea, or vomiting or diarrhea, should contact their health care provider. Their health care provider will determine whether influenza testing is needed.
Clinicians

Clinicians should consider the possibility of swine influenza virus infections in patients presenting with febrile respiratory illness who:

1. Live in San Diego County or Imperial County, California or San Antonio, Texas or
2. Have traveled to San Diego and/or Imperial County, California or San Antonio, Texas or
3. Have been in contact with ill persons from these areas in the 7 days prior to their illness onset, or
4. Have been in contact with ill persons from these areas in the 7 days prior to their illness onset, or

If swine flu is suspected, clinicians should obtain a respiratory swab for swine influenza testing and place it in a refrigerator (not a freezer). Once collected, the clinician should contact their state or local health department to facilitate transport and timely diagnosis at a state public health laboratory.
State Public Health Laboratories
Laboratories should send all unsubtypable influenza A specimens as soon as possible to the Viral Surveillance and Diagnostic Branch of the CDC’s Influenza Division for further diagnostic testing.
Public Health /Animal Health Officials
Officials should conduct thorough case and contact investigations to determine the source of the swine influenza virus, extent of community illness and the need for timely control measures.
More information about swine flu can be found on the CDC website at http://www.cdc.gov/flu/swine/index.htm.

• Page last updated April 23, 2009
• Content Source: Coordinating Center for Infectious Diseases (CCID)
• National Center for Immunization and Respiratory Diseases (NCIRD)