The following is an excerpt.
The new H7N9 bird flu strain continues to spread across China. Currently, more than 120 cases had been reported across 10 provinces, and 24 deaths. Yet no one knows where the virus started, which hampers efforts to contain it. But a promising new antiviral drug may help tackle flu in the future.
In an attempt to find the source, Chinese labs have tested 68,000 samplessince early March. They have been taking swabs on farms and live animal markets, both from birds and the surfaces they’ve been in contact with. Only 46 of those samples, scattered across central and eastern China, carried the H7N9 virus: 44 from markets selling live poultry, one from urban racing pigeons and one from a wild pigeon. “Not one farm tested positive,” says Juan Lubroth, chief veterinary officer of the UN Food and Agriculture Organization in Rome, Italy.
Genetic differences between the samples suggest the virus has been spreading in animals for a few months. But which animals? The carriers found to date were too far apart to sustain an epidemic.
View the original article here: Where has H7N9 bird flu come from?