- "The death of a Chinese girl with flu-like symptoms
in a village where a bird flu outbreak had been reported was caused by
pneumonia acute respiratory difficulty, local health authority cited initial
blood tests result as saying on Thursday.
- Latest tests on the girl's blood sample have turned out
negative for the avian influenza virus, and doctors said she had died of
severe pneumonia with acute respiratory difficulty, according to the provincial
center for disease prevention and control.
- The 12-year-old He Yin died recently after eating a dead
chicken in Wantang Village, in Xiangtan County of central China's Hunan
Province, where the latest outbreak of H5N1 avian influenza was reported
several days ago."
- The above description provides additional evidence that
the cause of the girl's death was H5N1. On Tuesday, China filed an OIE
report indicating that H5N1 had been detected at Wantang Village and was
killing chickens and ducks. The death and/or bird flu symptoms in two
children that had eaten a dead chicken in the village strongly suggests
the severe pneumonia was due to H5N1. Negative data means little if there
is no positive data identifying the micro-organism that caused the pneumonia.
- The outbreak in Wangtang follows reports of outbreaks
in AnHui, Inner Mongolia, and Mongolia and strongly suggests that the H5N1
detected at each location was the H5N1 wild bird flu closely related to
H5N1 from Qinghai Lake. This homology was subsequently found in Russia,
Kazakhstan, Romania, Turkey, Croatia, and Moldova. Although human cases
have not been confirmed. Boxun reports on the Qinghai outbreak described
human cases and pneumonia cases in Russia and Kazakhstan have been described.
Like the Hunan cases, the victims had pneumonia, H5N1 exposure, but tested
negative for H5N1. Since these additional cases also cited pneumonia but
offered no positive data on the etiological agent of the pneumonia, H5N1
remains highly suspect in all three countries.
- Human infection by wild bird H5N1 is cause for concern.
As the number of H5N1 versions that cause human infections increase, the
likelihood that H5N1 in wild birds does not cause human infections descreases.
In 2004, the only reported human H5n1 cases were in Vietnam and Thailand
and isolates from the two countries were similar as were case fatality
rates. However, in 2005 a milder version of H5N1 emerged in northern Vietnam,
while a more lethal version was found in southern Vietnam and Cambodia.
This there were two versions of H5N1 co-circulating in Vietnam.
- Similarly, the first human cases in Indonesia were reported
in 2005 and there may be milder version there also. Some reports have
described two distinct versions of H5N1 in Indonesia. Therefore the number
of H5N1's that are variations of the Z genotype continue to increase, which
increases the likelihood that the Z genotypes in wild birds can infect
humans. Indeed, the dramatic increase in human cases in Indonesia, including
those linked to the Ragunan Zoo were blamed on H5n1 from wild birds and
Thailand has Laos suggested that the sudden increase in human and poultry
infections in Thailand are linked to wild birds.
- This increase in versions of H5N1 raises serious questions
about a pandemic vaccine effort that targets a 2004 version of H5N1 and
ignores the emerging human versions that are linked to wild birds. The
current strategy is to wait for a reassortment event, and there is little
data to support such a prediction.
- All 8 genes from the 1918 pandemic strain are now public,
and there is no reassortment with a human gene. Similarly, the new versions
of the Z genotype iof H5N1 do not involve reassortment. Rather the H5N1
is recombining to produce drifts that evade the earlier immune response
on organisms infected with H5N1
- Thus it is time to reconsider a pandemic vaccine effort
that waits for a event of low probability and ignores the diversity in
H5N1 infecting humans in 2005.
- © 2005 Recombinomics. All rights reserved.