Virus circulating in Africa and Europe could be more threatening to humans

Scientists at the University of Wisconsin-Madison are reporting important mutations in the H5N1 virus circulating in Africa and Europe

"Birds usually have a body temperature of 41 degrees Celsius (106 degrees F), and humans are 37 degrees C (98.6 degrees F) usually. The human nose and throat, where flu viruses usually enter, is usually around 33 degrees C (91.4 degrees F).
'So usually the bird flu doesn't grow well in the nose or throat of humans,' {Dr. Yoshihiro Kawaoka of the University of Wisconsin-Madison} said. This particular mutation allows H5N1 to live well in the cooler temperatures of the human upper respiratory tract."

Recent samples of the virus taken in Africa and Europe all had this particular mutation

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