Chinese researchers speculate that Influenza A(H7N9) could cause a severe pandemic
In an article entitled, Epidemiological and risk analysis of the H7N9 subtype influenza outbreak in China at its early stage published in the Chinese Science Bulletin, Chinese researchers review the case data on human A(H7N9) infections and conclude that there is high risk of A(H7N9) causing a pandemic. They speculate that such a pandemic would be severe and have a higher mortality rate than the recent 2009 H1N1 pandemic.
From the article:
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In an article entitled, Epidemiological and risk analysis of the H7N9 subtype influenza outbreak in China at its early stage published in the Chinese Science Bulletin, Chinese researchers review the case data on human A(H7N9) infections and conclude that there is high risk of A(H7N9) causing a pandemic. They speculate that such a pandemic would be severe and have a higher mortality rate than the recent 2009 H1N1 pandemic.
From the article:
In light of the above considerations, we think that the H7N9 outbreak is severe, and it is likely to become very or extremely severe in the future, highlighting the emergent need of forceful scientific measures, such as building enough stockpile of H7N9 vaccine for human use in case the pandemic really occurs. . . .We do not exclude completely the possibility that the H7N9 will disappear naturally, or maintain its low pathogenicity in birds and limited transmission ability in humans for a long period, without forceful scientific control measures. However, such a mild scenario of the outbreak evolution is of less possibility than the very or extremely severe scenario describe above. The main reason is that some random mutations leading to the improved adaption of the virus to humans will emerge naturally during its long existence in humans, as the virus usually evolves rapidly. These mutants will become dominant by natural selection as they are more adaptive in humans. They thus may spread in humans rapidly and can spark a deadly pandemic. Similarly, the H7N9 virus of low pathogenicity in birds is more likely to become highly pathogenic through natural selection. . .
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