HONG KONG - Yi Guan has extensive experience zero of an epidemic. In spring 03, the virologist at Hong Kong University (HKU) isolated the SARS virus in masked palm civets a wild animal market in Guangdong province of China. When the virus erupted again in late 03, the recommendation of his team to shoot down all the civets in captivity in the region may have been the key to stopping SARS in its tracks. The virus has not reappeared since
Although SARS is its claim to fame, Guan has spent most of his career studying the flu after getting a doctorate under the expert swine flu the eminent influenza Robert Webster research Hospital St. Jude children in Memphis, Tennessee. He is currently working with the group of Webster.
Guan has been highly critical of what he sees as the WHO slow response to the H1N1 emergency. He took a break for a few hours of marathon in the laboratory and conference call 3:00 with US colleagues to speak with Science Insider
-Richard Stone
. Q: Where did go wrong WHO
YG: Friday [24 April] night I was at Bombay airport, waiting for a Hong Kong flight home. They [WHO and CDC] already knew the situation in Mexico. Mexico said they had transmission from human to human, and MMWR [ Morbidity and Mortality Weekly Report ] reported three cases in America - these cases were community cases. He was already an epidemic in the United States, although it was not severe, he did not kill people. I was always optimistic that we could contain H1N1. Then nothing happens every weekend
Q :. So, WHO raised the level of alert earlier
Y.G:. Yes! WHO should have gone in level 4 or even at level 5 on Friday. We missed the golden period to contain the virus. Several hours may still be a few hundred cases. Every second was precious in those days. We made a huge mistake. From there, he was the countdown to the pandemic
Q:.? Why is there have been dozens of deaths in Mexico, but the case most of the mild weather in other countries
YG :. We still do not have clues why this virus is more mild outside Mexico
in the initial stage of reassortment [genetic mixing with other viruses], most influenza viruses have low fitness. Their genomes are composed of eight gene segments. The reassortment event forms a new family with eight members. You can say they may have a family conflict. This kind of conflict makes reassortant behavior very strange virus
Q:.? Is it surprising how quickly H1N1 adapted
YG: All viruses, after interspecies transmission, will evolve rapidly. But why this H1N1 could succeed efficient human to human transmission is still unknown. We have a lack of knowledge of how influenza A viruses build their pandemicity humans. As swine H1N1 has being circulating in pigs since 1918, it has accumulated [many] differences of H1N1 human virus. So for humans, it looks like a new subtype, like most human individuals lack immunity to this H1N1 swinelike. This is one of the most important conditions for pandemic emergence. The new virus will develop into a more virulent strain - like the Spanish flu in the fall of 1918, killing more people - we do not yet have an idea
. Q: It depends other mutations
YG: This depends on if the mutations and other viruses restocking with other virus - like H5N1 ?. This could be a super nightmare for the whole world
Q:.? You speak of Armageddon virus
YG: The chance is very, very low that these two viruses mix, but we can not rule out the possibility. Now, the H5N1 virus is in more than 60 countries. It is a panzootic, everywhere except in North America
Q :. If the nightmare becomes reality
YG: If this happens, I will withdraw immediately and lock myself in the P3 laboratory. H5N1 kills half the people it infects. Even if you inject with a vaccine, it may be too late. Maybe in a few hours, it takes your life
Q:.? What have you learned from your work on H1N1 thus far
YG: We almost understand how the H1N1 virus has been generated - its evolutionary path. The virus has all the genetic markers that allow us to track how and where it comes from. We have a huge tree [a family tree of influenza variants], a long history. My former supervisor here at HKU, Ken Shortridge, started the surveillance of influenza in 1976. At each point where the changes of the influenza virus, we made a record
Q :. Any truth to the speculation [in Chinese media] China native virus
YG: actually, in this case, we can not blame China. What is interesting, the reassortant four or five times
Q:.? Is it surprising that you can have as reassortment and still have a viable organization
YG: Yes, absolutely! Basically, we understood where the virus originated, and writing a paper. But where and how it jumped into humans - to be developed in the US
Q: What are the other major knowledge gaps
YG: Each year, we meet many reassortant viruses, we do not know what can jump to humans. Which could become a pandemic? Nobody knows. We lack the knowledge to distinguish which virus has pandemic potential. . This is a great limitation
Many of us influenza researchers, we blame ourselves; if we have this knowledge, we can get rid of pandemics in humans. Life becomes very significant if you do something like that. SARS has been avoided for 6 years. But I work 20 years on influenza. I still do not know which variant will cause a pandemic. I feel frustrated by this. In my life, I will not be able to solve this problem. Fortunately, my students will be
Q:.? Are you surprised there has not been a SARS epidemic in 03
YG: The ecosystem was disrupted. No more large amounts of wild animals on the market, right next to your door. It was like a big mixing vessel. As a PCR machines [polymerase chain reaction]. Put the virus and amplify it. That is why my group has worked so hard to study the ecosystem H5N1. We take about 50,000 to 60,000 birds per year, about 0 per day. Like a factory. It is a very mechanical work, very dangerous work
Q :. Someone has to
Y.G: .. Yes! How can you compare an epidemic with peaceful time? This information will be essential to understand H1N1
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