KUMAMOTO - Restrictions on poultry shipments put in place due to an outbreak of highly virulent avian influenza in Taragi, Kumamoto Prefecture, have been lifted because recent tests for the virus have all been negative, the prefectural government said Thursday.
Infection-control operations based on lessons learned in past outbreaks of foot-and-mouth disease and bird flu are seen as having helped prevent the virus from spreading to other farms.
The prefecture has been conducting infection testing at two other poultry farms in the movement-restricted area designated on April 27 within a three-kilometer radius around the poultry farm where the outbreak occurred. Visual examinations of about 37,000 birds revealed no abnormalities. The prefecture announced that serum-antibody tests and virus-isolation tests performed on blood and other samples from chickens in the restricted-movement area have revealed no new infections.
Though the prefecture lifted a general ban on outside shipments from areas three to 10 kilometers from the farm where the outbreak occurred, restrictions on the movement of chickens and eggs inside the restricted area will remain, likely until May 8.
"I felt I had to report it quickly, so what happened before wouldn't repeat itself," the manager of the poultry farm where the outbreak occurred told The Yomiuri Shimbun in a telephone interview.
The man was referring to massive outbreaks of bird flu that occurred in 2010 and 2011. Infections in neighbouring Miyazaki Prefecture were not controlled, and 1.02 million birds at 13 farms had to be slaughtered.
On April 11, the man discovered several dozen dead birds in one of his chicken coops. After more than 100 birds died the next day, he suspected an outbreak.
He called a veterinarian, who performed simple testing. The results were positive, and he quickly contacted the Kumamoto prefectural government.
If no new infections occur, even the farm where the outbreak occurred could be reopened soon.
"I still think, 'Why me? Why now?' but I'm glad it didn't spread to other [farms]," the man said.
Highly virulent avian influenza, such as H5 subtypes, infects poultry and can cause large numbers of deaths.
Infection of humans, while rare, can occur if birds' internal organs are handled or large amounts of fecal dust are inhaled. Human infections have been reported in China and countries in Southeast Asia.
Infected meat is not dangerous if fully heated to at least 70 C.