|A) Yes. WHO has some evidence that the H5N1 strain may have been circulating in birds since April 2003. The detection so far of only a few human cases suggests that the virus may not be easily transmitted from birds to humans at present. However, the situation could change quickly, as the H5N1 strain has been shown to mutate rapidly and has a documented propensity to exchange genes with influenza viruses from other species.
In situations that could favour the emergence of a new pandemic strain of influenza virus, every case of human infection is one too many. In addition to the rapid destruction of infected animals, another opportunity to prevent human cases is through the protection of workers involved in culling operations. WHO has issued guidelines for conducting these operations safely.