Becky,
Thanks for the response. I understand that it's not productive to try to prevent one type of viral disease with a vaccine against another virus. However, Tamiflu is believed to work by inhibiting the viral enzyme neuraminidase, which is present in influenza A viruses, and avian flu is an influenza A virus. Why wouldn't Tamiflu have an effect on the avian flu virus, if it's mechanism of action is to inhibit neuraminidase?
That vaccines against other influenza A viruses are not effective against the avian flu virus is a different matter, having to do with the H5 molecule being an antigen that humans do not have previous exposure to and subsequent immunity against.
I think you may be confusing the likely mechanism of action of Tamiflu with the mechanism of action of vaccines. Avian flu virus may be developing resistance to Tamiflu, but it is apparently mostly susceptible at this point in time (or it wouldn't be developing resistance).
cnews.canoe.ca
This is from one of your links:
users.rcn.com
The hemagglutinin of the 1918 flu virus was H1, its neuraminidase was N1, so it is designated as an H1N1 "subtype". Here are some others.
Some strains of influenza A Date Strain Subtype Notes
1918 being studied H1N1 pandemic of "Spanish" flu
1957 A/Singapore/57 H2N2 pandemic of "Asian" flu
1962 A/Japan/62 H2N2 epidemic
1964 A/Taiwan/64 H2N2 epidemic
1968 A/Aichi/68 H3N2 pandemic of "Hong Kong" flu
1976 A/New Jersey/76 H1N1 swine flu in recruits
In October 2003, an epidemic of influenza in chickens began sweeping through several countries in the Pacific Rim (Vietnam, Thailand, Japan, China, South Korea, Cambodia). The virus is H5N1. The H5 molecule is common among bird influenza viruses but has not been seen on flu viruses that cause human epidemics. However, sporadic human cases of H5N1 (with an alarmingly-high fatality rate) have been occurring ever since.
As a glance at the tables above will show, humans have had long experience with infections and vaccines by both H1 and H3 flu viruses. But the human population has absolutely no immunity against any H5 viruses. Has the ground been prepared for another worldwide pandemic?
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