Avian influenza is spreading in Japan. Apparently wild birds that migrated to this country have triggered the spread of the flu. In December, avian flu was confirmed in a poultry farm in Yasugi, Shimane Prefecture. Then it was found in swans in Yonago, Tottori Prefecture, and Takaoka, Toyama Prefecture, and in hooded cranes in Izumi, Kagoshima Prefecture. It is very likely that more wild birds are infected with avian flu.
In late January, avian flu broke out in poultry farms in such places as Miyazaki city; Shintomi and Tsuno, Miyazaki Prefecture; Izumi and Toyohashi, Aichi Prefecture. In Japan, Yamaguchi Prefecture saw an outbreak of highly pathogenic avian flu in January 2004 — the first such outbreak in 79 years. Since then, there have been sporadic cases.
Outbreaks this time are of a large scale and threats of avian flu have entered a new stage. Poultry farmers and veterinarians are urged to be vigilant and to report irregularities immediately to authorities.
Wild birds such as wild ducks that are carriers of avian flu virus fly to Japan from the north in winter. Since infected wild birds are flying over the whole of Japan, any poultry farm can be a victim of the flu. Perhaps the first detected case of avian flu virus this winter season is a highly virulent H5N1 strain found in wild duck droppings in Wakkanai, Hokkaido, in October 2010.
The basic countermeasure available for poultry farmers is to use strong nets to ward off wild birds. Once flocks of poultry are found to be infected with the avian flu virus, they must be slaughtered.
The Domestic Animal Infectious Disease Control Law bans the transfer of chickens and eggs that exist within a 10-km radius of an affected farm.
In cases where poultry farmers must slaughter a large number of chickens, the government should provide an appropriate amount of compensation and other support. Guarding against avian flu should not slacken because not only wild birds but also animals and humans can carry the flu virus.