The World Health Organization is calling on countries to keep a close watch on outbreaks of avian flu, stressing that fresh infections have been reported in birds in nearly 40 countries since November. 
WHO Director-General Margaret Chan was speaking at an executive board meeting in Geneva on Monday. 
She said highly pathogenic avian influenza outbreaks in poultry or wild birds have shown a steep increase. She said the WHO has been put on high alert by the rapid geographical expansion of the outbreaks and the number of virus strains currently co-circulating. 
She noted that the H5N6 virus causing severe outbreaks in Asia is a new strain created by gene-swapping among 4 different viruses. 
She added that China has reported epidemics of the H7N9 infection in humans since 2013, with more than 1,000 cases confirmed. 
Chan warned that in the most recent clusters, the WHO could not rule out limited human-to-human transmission.

Source: QNA