Russia has registered the world’s first case of human infection with a strain of bird flu named A(H5N8).
Other strains, such as H5N1, H7N9 and H9N2, have been known to spread to humans.
Russia reported the case of human infection to the WHO “several days ago, just as we became absolutely certain of our results”, Ms Popova said on state television, Russia-24.
There was no sign of transmission between humans so far, she added.
The majority of bird flu infections in humans have been associated with direct contact with infected live or dead poultry, though properly cooked food is considered to be safe.
Bird flu outbreaks often prompt poultry plants to kill their birds to prevent the virus from spreading and avoid trade restrictions from importing countries.
The vast majority of cases are spread by migrating wild birds, so producing countries tend to keep their poultry indoors or protected from contact with wildlife.
Seven workers at a poultry plant in south Russia had been infected with the H5N8 strain when there was an outbreak at the plant in December, Ms Popova said, adding that the individuals involved felt fine now.
“This situation did not develop further,” she said.
Siberia’s Vector Institute said on Saturday it would start developing human tests and a vaccine against H5N8, RIA news agency reported.
The WHO did not reply to a request for comment. – Reuters