H7N9 update:
h7n9-bird-flu-strain-china-pandemic-potential-u-s-japanese-lab-studies-find/
From above link:
The H7N9 virus has been circulating in China since 2013, causing severe disease in people exposed to infected poultry. Last year, human cases spiked, and the virus split into two distinct strains that are so different they no longer can be treated with existing vaccines.
One of these has also become highly pathogenic, meaning it has gained the ability to kill birds, posing a threat to agriculture markets.
U.S. and Japanese researchers studied a sample of this strain to see how well it spread among mammals, including ferrets, which are considered the best animal model for testing the transmissibility of influenza in humans.
In the study, published in the journal Cell Host & Microbe, flu expert Yoshihiro Kawaoka of the University of Wisconsin and colleagues tested a version of the new H7N9 strain that was taken from a person who died from the infection last spring.
They found that the virus replicated efficiently in mice, ferrets and nonhuman primates. It also caused even more severe disease in mice and ferrets than a low pathogenic version of the virus that does not cause illness in birds.
To test transmissibility, the team placed healthy ferrets next to infected animals. The virus spread easily from cage to cage, suggesting that it can be transmitted by respiratory droplets such as those produced by coughing and sneezing.
Two out of 3 healthy ferrets infected in this way died, which Kawaoka said is “extremely unusual” and suggests that even a small amount of virus can cause severe disease.
“The work is very concerning in terms of the implications for what H7N9 might do in the days ahead in terms of human infection,” said Michael Osterholm, an expert on infectious diseases at the University of Minnesota.
Since 2013, the H7N9 bird flu virus has sickened at least 1,562 people in China and killed at least 612. Some 40 percent of people hospitalized with the virus die.
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Thought about this when viewing an article about the great 1918 Influenza Pandemic coming up on 100 years ago. Killed tens of millions, more than the Great War. The total number is still unknown.
In case you don't know:
http://www.history.com/topics/1918-flu-pandemic
