Sunday, April 21, 2013

Gene data show China bird flu mutated "under the radar"

The new strain of bird flu that has killed 17 people in China has been circulating widely "under the radar" and has acquired significant genetic diversity that makes it more of a threat, scientists said on Friday.

Dutch and Chinese researchers who analyzed genetic data from seven samples of the new H7N9 strain say it has already acquired similar levels of genetic diversity as much larger outbreaks of other H7 strains of flu seen previously in birds.

"The diversity we see in these first few samples from China is as great as the diversity we have seen with a large outbreak in the Netherlands several years ago and one in Italy," said Marion Koopmans, head of virology at the Dutch National Institute for Public Health and the Environment, who worked on the study as part of a nine-member team.

"This means it (the H7N9 strain in China) has been spreading quite a bit and it's important to understand where exactly that is going on."