Russia announced on Saturday that its scientists had detected the world's first case of transmission of the H5N8 strain of avian flu from birds to humans and had alerted the World Health Organization.
In televised remarks, the head of Russia's health watchdog Rospotrebnadzor, Anna Popova, said scientists at the Vektor laboratory had isolated the strain's genetic material from seven workers at a poultry farm in southern Russia, where an outbreak was recorded among the birds in December.
The workers did not suffer any serious health consequences, she added. They are believed to have caught the virus from poultry on the farm.
Information about the world's first case of transmission of the avian flu [H5N8] to humans has already been sent to the World Health Organization, Popova said.
There are different subtypes of avian influenza viruses. While the highly contagious strain H5N8 is lethal for birds, it had never before been reported to have spread to humans.
Popova praised the important scientific discovery, saying time will tell if the virus can further mutate.
The discovery of these mutations when the virus has not still acquired an ability to transmit from human to human gives us all, the entire world, time to prepare for possible mutations and react in an adequate and timely fashion, Popova said.
The WHO confirmed Saturday that Russia had notified it of the development.
WHO stressed that the Russian workers were asymptomatic and that no onward human-to-human transmission had been reported.
People can get infected with avian and swine influenza viruses, such as bird flu subtypes A(H5N1) and A(H7N9) and swine flu subtypes such as A(H1N1).
According to the WHO, people usually get infected through direct contact with animals or contaminated environments, and there is no sustained transmission among humans.
Russia's Vektor State Virology and Biotechnology Center, which detected the transmission to the poultry farm workers, also developed one of the country's several coronavirus vaccines. In the Soviet era the lab, located in Koltsovo outside the Siberian city of Novosibirsk, conducted secret biological weapons research and it still stockpiles viruses ranging from Ebola to smallpox.