MOSCOW - A Russian official reported a fourth outbreak of dead domestic poultry in a suburban Moscow district Sunday as experts tightened quarantines following confirmation of the presence of the H5N1 bird flu strain.
The presence of H5N1, confirmed by tests late Saturday, was the first such outbreak to be recorded so close to the Russian capital.
Dead domestic fowl were reported Sunday in the Taldom district, north of the capital, Andrei Barkovsky, a spokesman for the Moscow regional governor, told Ekho Moskvy radio, though it was unclear exactly when the birds died occurred.
Earlier, officials with the federal agricultural oversight agency Rosselkhoznadzor said that three districts west and south of Moscow had recorded bird deaths.
Agency spokesman Alexei Alexeyenko said late Saturday that tests had confirmed H5N1 in poultry found dead in two districts, Odintsovo and Domodedovo, where two dozen birds died this week. Results of tests taken in the Podolsk district, where nearly four dozen birds died, were pending.
Officials said several people who were in close contact with the dead poultry were taken in for medical observation, but no health problems had been reported.
Russian television broadcast footage showing veterinary workers clad in protective suits checking homes in one district and spraying vehicle tires with disinfectant, while police began enforcing a quarantine in an effort to prevent the virus' spread.
Regulators also shut down an outdoor poultry market in Moscow where some of the dead birds appeared to have been bought and Nikolai Vlasov, a senior Rosselkhoznadzor veterinary official, warned that more outbreaks were possible.
No human cases of bird flu have been reported in Russia, which had its first reported cases of the H5N1 strain in Siberia in 2005. Outbreaks have since occurred farther west, but mostly in southern areas distant from the capital.
Since it began ravaging Asian poultry farms in late 2003, the H5N1 strain has killed at least 167 people worldwide, according to the World Health Organization.
Though it remains difficult for humans to catch, health authorities across the globe are monitoring the H5N1 strain out of concern it could mutate into a form that easily spreads from person to person and spark a pandemic.