13 August 2007
Indonesia Still Not Sharing Virus Samples for Avian Flu Vaccines
U.S. scientists create H5N1 vaccine that could target emerging virus
Washington -- Despite agreeing to share viruses with the World Health Organization (WHO) in March, Indonesia -- the nation with the highest rates of infection and death from highly pathogenic avian influenza -- still has not done so.
All countries except Indonesia are sharing human samples of the H5N1 avian flu virus with the WHO Global Influenza Surveillance Network so experts can assess the risk that a viral strain might mutate to pass easily from person to person and so diagnostic tests and vaccines can be developed. (See related article.)
By not sharing viruses, said Dr. David Heymann, WHO assistant director-general for communicable diseases, during an August 6 press briefing, Indonesia is “putting in danger its own population, because if those viruses are not freely shared with industry, vaccines will not contain the elements of the Indonesia infection.”
This also puts the world’s public health security at risk, he said.
On July 11, Indonesia confirmed its 102nd human case of avian flu in a 6-year-old girl from Banten. So far, WHO has confirmed that 81 people have died there from the virus. Around the world, since 2003, 319 people have fallen ill from H5N1, and 192 have died. (See related article.)
Heymann was reporting on the results of a five-day meeting in Singapore, where representatives of 24 countries met beginning July 31 to discuss issues related to virus sharing and equitable distribution of vaccines among rich and poor nations.
In May, the WHO World Health Assembly passed resolution 60.28, which outlined the flow of activities designed to ensure “that countries received the benefits they felt they would need from virus sharing,” Heymann said.
Singapore was the first meeting in that process; the next meeting will be held in Geneva in early November. The end-point of the process should be the 61st World Health Assembly, to be held in May 2008.
Under the resolution, a new stockpile of H5N1 vaccine has been established, initially containing 50 million doses donated by GlaxoSmithKline. WHO Director-General Margaret Chan was asked to develop a mechanism for benefit sharing among countries, and the stockpile is part of that effort. The director-general also will commission a report on intellectual property relating to virus ownership.
“WHO is now working to determine the mechanism that will govern this vaccine and make sure that it’s equally distributed around the world to countries in need,” Heymann said.
Stockpiling is a short-term benefit-sharing mechanism. In the medium and long term, developing countries have asked for a transfer of technology so they can produce vaccines in their own countries.
WHO has given grants to six developing countries to transfer vaccine production technology using resources provided by the United States, Japan, Canada and the Asian Development Bank.
In the United States, a team of scientists at the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, and a collaborator at Emory University School of Medicine in Georgia are preparing vaccines and drugs that could target predicted H5N1 mutants before the viruses evolve naturally.
“While nobody knows if and when H5N1 will jump from birds to humans, [the team has] come up with a way to anticipate how that jump might occur and ways to respond to it,” said NIH Director Elias Zerhouni, in an August 9 statement.
Making a vaccine against an H5N1 strain or another flu virus is fairly routine. Samples of flu virus strains are isolated and then grown in eggs or cell cultures. The virus then is collected, inactivated, purified and added to the other components of the vaccine.
A flu shot prompts a person’s immune system to detect pieces of the inactivated virus in the vaccine and make neutralizing antibodies against them. Later, if the same person is exposed to a flu virus, the antibodies should help fight the infection.
But flu viruses constantly mutate and vaccines are most effective against the specific strains from which they are made. That makes it difficult to predict how effective a vaccine made today will be against a virus that emerges tomorrow.
BIRD FLU AND PEOPLE
Led by Dr. Gary Nabel, director of NIAID’s Vaccine Research Center, the team focused on mutations that let H5N1 bird viruses more easily recognize and enter human cells.
Bird-adapted H5N1 binds to places on the bird cell called surface receptors. These receptors differ slightly from the receptors on human cells, which is partly why bird-adapted H5N1 can infect but not spread easily among people.
The team found that the mutations change how the immune system recognizes the virus and used this knowledge to create vaccines and isolate new antibodies that might be used against human-adapted virus mutations.
They vaccinated mice with the material from viruses they altered to contain the mutations and discovered one antibody that could neutralize the bird- and the human-adapted forms of an H5N1 virus.
“This research could possibly help to contain a pandemic early on,” said NIAID Director Anthony Fauci.
For more information on U.S. and international efforts to combat avian influenza, see Bird Flu.
(USINFO is produced by the Bureau of International Information Programs, U.S. Department of State. Web site: http://usinfo.state.gov)
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