Avian influenza information sharing and stockpiling solution
World Health Organization (WHO) member countries continue to try to resolve the dispute over avian influenza virus sharing that threatens global influenza surveillance and vaccine development.
There is an increasing reluctance among developing nations to share the virus samples they have collected based on what they believe is an unfair distribution of the resulting vaccine between developed nations and themselves. Most of the 250–300 million vaccine doses developed each year from these virus samples reach the residents of developed countries, despite the fact that up to 70% of human influenza A(H5N1) infections resulting in mortality occur in Asia.
Amid the discussions, Laurie Garrett, Senior Fellow for Global Health at the Council on Foreign Relations, New York, and David Fidler, Professor of Law and Director of the Center on American and Global Security at Indiana University, have offered a novel proposal whereby supplies of over 500 million doses of influenza vaccine, plus antiviral medicines, protective masks and gloves, and germicide washes will be stockpiled in Hong Kong. The Asia-Pacific Economic Cooperation forum (APEC) would manage the required funding and stockpiled materials and, in conjunction with the WHO, decide when and how to distribute the materials. In addition, APEC may also have the political influence necessary to persuade hesitant nations to share new viral samples with the WHO on an urgent, timely, and consistent basis.
For now, Indonesia’s willingness to resume virus sharing may depend on the outcome of intergovernmental negotiations in Geneva this month (November 2007).
[Garrett L, Fidler DP. Sharing H5N viruses to stop a global influenza pandemic. PLoS Med 2007; 4: e330.]
Avian influenza claims another victim
The Indonesian Ministry of Health announced that a 31-year-old Indonesian man has died of a human influenza A(H5N1) infection.
The man, from the Bengkalis District of Riau Province in Sumatra Island, developed symptoms on 31 October, sought treatment and was hospitalised on 3 November. He died 3 days later just after he was admitted to Pekanbaru’s Arifin Achmad Hospital, an avian influenza referral hospital, on 6 November.
The source of infection is yet to be determined with further investigation pending. However, the primary investigation will include the examination of a large swallow farm in close proximity to the deceased’s home.
Of the 113 human cases of H5N1 avian influenza infection confirmed to date in Indonesia, this death marks Indonesia’s 91st fatality – the world’s highest number of fatal cases. Worldwide, there have been 335 cases and 206 mortalities from human H5N1 infections since 2003.
[World Health Organization. Epidemic and Pandemic Alert and Response (EPR). Disease Outbreak News. Avian influenza – situation in Indonesia – update 24. 12 November 2007. Available at: www.who.int/csr/don/2007_11_12/en/index.html. Accessed 26 November 2007.]
Children more susceptible to bird flu
A new study suggests that influenza A(H5N1) virus binds more easily to the cells in the respiratory tract of children than to those in adults. This may explain why avian influenza infects children more readily than it does adults.
A team of researchers from the University of Hong Kong and the Adelaide Women and Children’s Hospital in Australia have used molecules called MAA (Maackia amurensis agglutinin) to identify the receptors for avian viruses, including H5N1, in tissue specimens of the human respiratory tract. They found that MAA displayed widespread binding throughout the respiratory tract, but was particularly good at binding to children’s cells in the lower respiratory tract as well as cells in the upper respiratory tract of adults.
Lead researcher Dr John Nicholls said, “Understanding the how and why of avian virus infection of humans is a very complex process involving research into properties of H5N1 virus, the host receptor and the cellular response.”
“We believe that the studies we have done investigating where the receptors are located and their distribution with age is a small step towards unravelling this process and [will] help in finding ways to diminish the potential treat from this emerging infection.”
[BioMed Central. Bird Flu Finds Children’s Lungs Faster. ScienceDaily, 27 October 2007. Available at www.sciencedaily.com/releases/2007/10/071025080905.htm. Accessed 9 November 2007.]
Rural kids show weaker immune response to flu vaccine
Influenza vaccination induces weaker immune responses in a rural population than those found in a semi-urban population of schoolchildren in Gabon, Africa. This is the finding of a recent study to be published in the 1 December issue of the Journal of Infectious Diseases.
The study was performed as little is known about influenza in Africa. The researchers analysed the seroprevalence of antibodies to influenza viruses prior to vaccination and found that influenza A viruses of the H1N1 and H3N2 subtypes and influenza B virus had already been circulating in Gabon. They also found that vaccine-induced antibody responses to H1N1 and influenza B strains were significantly higher in the schoolchildren from the semi-urban area than in the rural children. Although these differences could not be explained, the researchers noted that the two populations differed with respect to the rates of parasitic infections (higher in rural areas) and also nutritional status (poorer in rural areas).
[van Riet E, Adegnika AA, Retra K et al. Cellular and humoral responses to influenza in Gabonese children living in rural and semi-urban areas. J Infect Dis 2007; in press. Available at: www.journals.uchicago.edu/JID/journal/issues/v196n11/38547/38547.html. Accessed on 9 November 2007.]