Reassortant H7N2 bird flu in 2003 Westchester, New York case
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And we thought that bird flu news was slow recently. Recently, genetic sequences from a 2004 human case of H7N2 avian flu infection were released. The sequencing was dutifully covered by Dr. Henry Niman, among others.
Why it took a whopping four-plus years for the genetic sequences to be released is a matter of serious conjecture. But what is clear is this: the H7N2 was a reassortant virus that carried several human H3N2 pieces. The reassortant H7N2 virus was a matter of grave concern to the doctors and researchers, who were at a loss to explain how a New York man with zero contact with poultry could have contracted an avian reassortant.
From the New York Times story of April 20, 2004 (almost exactly four years ago):
Dr. Joshua Lipsman, the Westchester County health commissioner, said, "While we can't rule out it being person-to-person transmission, the likelihood is still very small." He added that the patient "had some potential exposures that we're looking into," but declined to elaborate.
http://www.nytimes.com/2004/04/20/nyregion/20flu.html?ei=5070&en=2ae918bf11e66f81&ex=1209528000&pagewanted=print&position
Officials said the man was infected with Type A influenza, Strain H7N2, the same one that hit chicken farms in New Jersey, Maryland and Delaware this year. The H7 viruses are thought to be less virulent in humans than the H5 strain that appeared in Southeast Asia in recent months. Other H7 strains were responsible for outbreaks in Canada this year, and in the Netherlands last year.
The Westchester patient, a Caribbean immigrant, lives in Yonkers with his wife and children, officials said. (Hospitals and health officials do not reveal the names of patients in cases involving public health issues.) He entered the hospital in November suffering from other serious ailments that weakened his immune system and that might have masked the symptoms of avian flu. One official said the patient had symptoms of a respiratory illness, including coughing and an abnormal chest X-ray. Doctors at first suspected tuberculosis.
"We knew it was something weird, but we didn't know what it was," said Claire Palermo Flower, spokeswoman for the hospital. "They did an elaborate culture and asked the lab to do more than the usual tests."
The county's laboratory tentatively identified the virus as a human flu strain, H1N1, and sent sputum samples to C.D.C. in Atlanta, said Ms. Flower and Dr. Cox. The specimen was set aside because few H1N1 cases were reported last winter, and the centers routinely concentrate on testing the most prevalent strains.
It was not until February that C.D.C. tested the sample, when scientists there found that the virus was not from the H1 group, Dr. Cox said. A subsequent test ruled out another family of flu viruses, Type B. Further testing showed that it was Type A, but not the H1, H3 or H5 subtypes.
Finally, on March 17, scientists using other tests identified the virus as H7N2. The next day, Dr. Cox said, C.D.C. notified health officials in New York that they had a suspect human case of avian flu. To be certain that the sample had not been contaminated in a laboratory, they did further tests.
Doctors asked the patient for another blood sample, to compare antibody levels in it with another sample kept from the initial phase of his illness. Last week, the tests confirmed a recent infection with H7N2, and the C.D.C. alerted state and local officials in a conference call on Friday.
Westchester officials and the state Department of Health have also tested the man's family, co-workers and close contacts - none of whom were sick - without finding evidence that any had also been infected.
C.D.C. officials said the federal agency did not believe that the case represented an imminent threat to public health.
Dr. Cox said C.D.C. reported the case Monday to the World Health Organization, which has repeatedly warned about the threat of avian flu. But a W.H.O. spokesman said that as of 5 p.m. in Geneva, where the agency is based, no such report had been received.
As we see, misdiagnosis and a lack of comprehensive testing tools contributed to this situation.
All this goes to show that while we stalk H5N1, another influenza or another disease entirely could sneak up on us and bite us in the surveillance read end. Just a few days ago, that concern was shared to me by Mike Coston (FLA_MEDIC). And he is right. H7, as we have seen repeatedly, is usually benign but is ridiculously easy for humans to catch. And it is not always benign: As we see in the 2003 Westchester case, the patient was quite ill. And in 2003, a Netherlands vet was killed by H7N7 that went from an outbreak in poultry to an outbreak in people.
Now why did it take four years to get this data?
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