- Petersen said that a genetic sequence analysis of the
virus from the dead woman, a 37-year-old worker at Jakarta's airport, had
just been completed in Hong Kong.
-
- The sequence showed that the virus was essentially the
same A(H5N1) avian influenza virus that had already been circulating in
poultry in Indonesia, he said.
-
- Malik Peiris, the Hong Kong University expert who did
the genetic sequence, cautioned that not all the virus had been analyzed
yet, but the segments analyzed so far match avian versions of the virus.
-
- This suggests that the virus has not mixed with human
flu viruses and thereby acquired the genetic material that would allow
it to pass more easily among people.
-
- The above comments indicate that the H5N1 in Indonesia
has not reassorted and is similar to H5N1 in poultry from Indonesia. The
same conclusion was reached for sequences from the earlier cluster in Indonesia.
-
- However, H5N1 has been found in several forms in human
since 1997 and none of these forms how evidence for reassortment with human
genes. Instead, H5N1 evolves via recombination, and most of the recombination
has generated small changes scattered through all eight genes. In many
instances the pieces of genes acquired have match mammalian sequences.
-
- Thus, the above data indicates the dramatic change in
H5N1's ability to infect humans is due to additional recombination. It
would be useful to make such sequence data public. There have been no
2005 sequences from Indonesia released, even though H5N1 is endemic in
poultry in Indonesia and was recently isolated from swine and people.
-
- The behavior of H5N1 clearly shows more efficient transmission
to humans. Release of the sequences will allow the determination of the
recombination that has led to this change. This is no evidence that reassortment
with human gene will be required. Indeed, H5N1 has achieved increased
transmission in humans and maintained a case fatality rate of 100%.
-
- Release of the sequence data of the virulent H5N1 would
be useful
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