Genesis of a Plague Right now, in a remote corner of rural China, a farmer and his family are sharing their water supply with their livestock: chickens, ducks, pigs, sheep. They share the same waste-disposal system, too. Bird viruses meet their human counterparts in the bloodstreams of the swine, where they mix and mutate before spreading back into the human population. And a new flu is born.... Dr. Noah Haldane, of the World Health Organization,...