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Sep 25

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Avian Influenza and the new SARS

I’ve just returned from a conference at Oxford entitled “Influenza 2012: One Influenza, One World.” The reference to “One World” in the

Avian influenza virus courtesy of dream designs at freedigitalphotos.net

title makes the point that human and animal health are intimately interlinked. While at the conference there was discussion of the current avian influenza outbreak in Jalisco, Mexico, and since returning there is now news about the discovery of a new corona virus in Saudi Arabia (this family of viruses covers a diversity of diseases from the common cold to SARS), which has killed one person and gravely sickened another. In this context, it makes sense to talk about the global ethical and scientific problems raised at the conference.

As Professor Hans-Dieter Klenk told the younger members of the audience, upon achieving a life-time achievement award, “Influenza will outlive you all.” There is a form of influenza (H17) in bats, and another form (H13) that is found in whales. There can be few diseases that infect as broad a spectrum of living beings on this planet as influenza. H5N1 (highly pathogenic avian influenza, or HPAI) is currently circulating in Egypt, Pakistan, and South East Asia. But there also outbreaks of HPAI that are not caused by H5N1, such as happened in the Fraser River Valley in Canada in 2004. While H5N1 gathers extensive attention, there is always the possibility that a pandemic form will emerge which is not from this clade of the virus. So there is a pressing need for new approaches.

One presenter argued that given the failure to create a universal vaccine, or adequately stamp out outbreaks amongst domestic waterfowl, the answer to avian influenza might be to genetically modify chickens so as to be resistant to the virus. He reported his team’s efforts to do this, although they did not have success. In order to be certain that the gene had been successfully introduced they accompanied it with a jellyfish gene that caused the chickens to glow neon green in the dark. For some reason –don’t ask me why- the effect was concentrated in the chicken’s gonads. From the attendees’ reaction when they saw the picture of the glowing chickens, I am not certain that people are ready to eat genetically modified poultry. The presenter noted some surveys about peoples’ attitudes and beliefs about genetically modified organisms in different European countries. These polls showed, for example, that people think that eating a genetically modified tomato might change their genes. Their point was that people reject GMOs in part out of ignorance. One attendee, who works with the pathogenicity of influenza, asked the presenter why his team didn’t just breed chickens to be resistant to influenza. That way, he suggested, you wouldn’t have to know how to prevent influenza in the chickens, and “even the Germans would eat them,” a reference to the deep distrust of GMOs in Germany. I couldn’t help but wonder, if this succeeds with chickens, what would you do next? Genetically modify pigs? Ducks are key vectors too. And what about all the other wild birds that carry the virus?

John Oxford, a key figure in influenza research, also talked about how we lack basic information about influenza’s transmission. For example, what percentage of people who are exposed to the virus become infected? How close do people have to be before they infected? How many people who are infected are asymptomatic? In order to answer these questions you would almost have to deliberately infect people with influenza, which is obviously impossible. But that’s exactly what Human Viral Challenge studies entail. Amazingly, volunteers come forward, who agree not only to be infected with the virus, but also to endure quarantine during the ten to fifteen days that they are observed. In fact, far more people volunteer than can possibly make it through an intensive screening process. The result is not only key information on influenza transmission –perhaps 25% of people develop a symptomatic infection after exposure, but a substantial number also have a subclinical infection- but also on the correlates of immunity that reflect recovery. In other words, by tracking peoples’ immune response from infection through recovery, it is possible to trace in detail how the immune system defeats the virus. To me, this seemed to be essential research, which I suspected would be impossible to do in the United States.

Another key issue discussed at the conference was the work of Ron Fouchier (Netherlands) and Kawaoka (U.S.), which showed how the HPAI could become readily transmissible through aerosols in mammals through passaging in ferrets. These studies have been bitterly controversial, because of fears that 1) the virus could escape and threaten others and 2) more importantly, that releasing this information could be dangerous, as terrorists could use it. After an extensive discussion, both studies have now been published. I had the good fortune to be able to hear Dr.  Fouchier discuss the issue. He made a powerful argument for the benefits of this work, and that many of the suggested risks were based on misinformation. Not being a scientist, it was difficult for me to judge the merits of the case, however, so afterwards I trend to get a sense of how other attendees perceived the issue. One person that I spoke with said that Fouchier had a point, but he had to slow down and wait for the guidelines and rules to catch up with this issue, but that they doubted that he would. My sense was that the people at the conference were divided themselves over the risks versus benefits of this line of research, even amongst those who did work with the pathogenicity of influenza. In the end, I thought –as a non-specialist in the field- that Fouchier’s work was valuable and merited publication, but that guidelines regarding this research were desperately needed for both researchers and journals, as my colleague had suggested.

There was also discussion at the conference of the avian flu outbreak (H3N7) that began in Jalisco, Mexico in June, 2012. One strongly voiced comment from a senior figure in the field was that the Mexican authorities had not moved quickly enough. There was a window of opportunity to contain the virus by culling infected flocks, and they had to “stamp it out.” The fact that the outbreak of HPAI was not H5N1 also emphasized the importance of not focusing on that threat in isolation.

I’ll talk in a future post about my own presentation on the World Health Organization’s Pandemic Influenza Plan. But I want to thank the conference organizers for the careful work that made for an outstanding event, and all my colleagues who patiently explained science to a social scientist. My only regret was that we did not have a chance to discuss the reemergence of a corona virus as a major health threat, as a man from Quatar was moved to London by air ambulance. For all of us with memories of the 2003 SARS outbreak this raised the question of what the future might hold, although it is quite possible that this virus will fade from view as quickly as it appeared. But I wish that I’d had the chance to talk about this with the virologists present. For anyone wanting to follow news in the area of avian influenza, and related topics, the best site is the CIDRAP website at the University of Minnesota. And if you would like to learn more about how international factors can shape the expression of an epidemic see my own book, The AIDS Pandemic in Latin America.

Shawn Smallman, Portland State University

Permanent link to this article: https://www.introtoglobalstudies.com/2012/09/avian-influenza-and-the-new-sars/