Bioscope ‘06

by  Dr. Barbara Price

Two Clades of H5N1
           In November 2003, a Chinese man died in Beijing from the flu. Originally it was thought he died from SARS, but recently (NEJM, 354:2731-273), the Chinese reported that it was H5N1 (A/Beijing/01/2003). The Chinese report this virus is a mixed strain and is different from the strain currently proposed for vaccine development (A/Vietnam/1203/2004). The authors suggest that perhaps effective vaccines will need to be developed from different regions to match the virus strains circulating there as is currently done in influenza vaccines. (A clade is a group of organisms with a common ancestor.)

           It is certain that researchers and medical doctors need to cooperate. To that end, many leading avian influenza scientists have tentatively agreed to share data as part of the Global Initiative on Sharing Avian Influenza Data (GISAID), announced in Nature on August 24.

          Novavax of Novartis reported on August 1, 2006 that it had designed a vaccine to protect against the H5N1 clade 2 influenza virus, the virus circulating in Indonesia.

          On August 11, WHO classified the H5N1 as follows:
Clade 1 Vietnam, Cambodia and Thailand 2003 and 2004;
Clade 2 Indonesia 2005 and 2006, which is further divided into six subclades, of which three have been involved in human disease:
Subclade 1, Indonesia;
Subclade 2, Middle East, Europe, and Africa; and,
Subclade 3, China.

          Based on this WHO is now offering three prototype strains to those wishing to try to make a vaccine: A/Indonesia/2/2005-like virus, A/Bar headed goose/Quinghai/1A/2005-like virus, and A/Anhui/1/2005-like virus. Of course, a question is will vaccines against these strains be effective against future mutations of H5N1.

Cooperation
How will the drug companies work together to find a vaccine or vaccines? An example may be seen in the cooperation for HIV drugs. This cooperation, the Doha agreement, has been hammered out over several years. If the avian flu evolves into a pandemic strain, we may not have the time to reach a similar agreement. We need to get our agreements in place now, at least in prinicipal. Recommended reading: How Do Intellectual Property Law and International Trade Agreements Affect Access to Antiretroviral Therapy?" by Michael Westerhaus and Arachu Castro and published online August 8, 2006.