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of stamping out or eliminating the disease, which is preferred in developed countries and by the World Organisation for Animal Health , is not feasible. The United States alone spent US$14.2 million on the first HPAI outbreak in 1925-1926. That figure ballooned to US$1.7 billion in 2022-2023 . “It’s really not sustainable with the increased outbreaks in poultry we’re seeing today and the reoccurrence of these outbreaks even in developed countries. This has become a huge economic burden just thinking of the US$1.7 billion that the US Government has paid and the losses that farmers and companies have had. It has also threatened food security. Just as an example, in the United States, a dozen table eggs which normally sell for about US$1 is now upwards of US$5, and the supply is quite short.” To prevent the introduction and spread of the pathogen, Dr. Swayne said the focus has been on implementing structural barriers to safeguard poultry raised inside barns and preventing the movement of the virus from the outside contaminated environment into the facility. However, as outbreaks continue across continents, there is now discussion on whether the vaccination should be used as a control tool. So far, 15 countries in which the virus has become endemic have undertaken the vaccination of birds for food security reasons. Dr. Swayne continued, “I think a question each country, including those in the Caribbean, will have to ask themselves is ‘Can we continue with just a stamping out programme or do we need to examine vaccination as an additional tool?’ “If you do use vaccination, you need to make sure that you match vaccines antigenically close to the outbreak virus so that you’ll have predictable protection, because poorly matched vaccines do not provide predictable protection.” u
Professor Thijs Kuiken Erasmus University Medical Center Netherlands
Dr. Richard Webby Director, World Health Organization (WHO) Collaborating Center
D irector of the WHO Collaborating Center for Studies on the Ecology of Influenza in Animals and Birds at St. Jude Children’s Research Hospital , Dr. Richard Webby , said the United Nations agency has been preparing for any eventuality. “What are the WHO and other entities doing about this? Regarding pandemic vaccine production, we’re not at a point yet where we need to go into full-blown vaccine manufacturing. We’re not seeing evidence that this virus is adapting to the human host yet. But what we do know is that it takes six months to make a matching strain should that change tomorrow,” he said. “The first part of the production system
is to make seed viruses [ viruses used to produce a batch of vaccines] that are manipulated in various ways before they can be sent to manufacturers. This occurs within WHO laboratories and takes a six- week period. So what the WHO is doing is trying to get a head start on this. As we see variants of the H5N1 emerging, we make that seed virus against some of the emerging strains just to have on the shelves so that if they change their minds from being a bird virus to being a human virus, we’ve shaved six months off the response.” The current strain of the avian influenza virus has become more widespread in the Eastern Hemisphere and the Western Hemisphere. But eradication programmes are expensive, said former director of the Southeast Poultry Research Laboratory in Georgia Dr. David Swayne. That facility operates as an international reference laboratory for avian influenza and Collaborating Center for Research on Emerging Avian Diseases. The avian pathologist concurred that the virus has become endemic in some wild bird populations that migrate across Asia, Africa, Europe, and North and South America. However, he said the process
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