The bird flu virus that killed about 3,500 chickens in southwestern Japan
last week was determined as the highly contagious and lethal H5N1 strain,
Japan's farm ministry said in a statement Tuesday.
According to National Institute of Animal Health which conducted the test,
the H5N1 detected in the poultry farm in Miyazaki prefecture was very infectious
and virulent.
The Agriculture, Forestry and Fisheries Ministry confirmed the cause of the
chicken death as avian influenza on Saturday and had the rest several thousands
of chickens in the farm culled during the weekend.
In an effort to find the infection routes, the ministry will examine possible
genetic similarity of the H5N1 virus detected in this case to those found in
other parts of the world, Kyodo News quoted ministry officials as saying
The H5N1 strain is a subtype of the influenza A virus that can cause illness
in humans and many other animal species. Since the first case of the virus'
human infection confirmed in Hong Kong in 1997, the strain has infected 265
people in 10 countries and led to death of 159 as of last Friday, statistics
from the World Health Organization showed.
It is feared that the bird-to-bird disease of avian flu currently spread
around the globe could mutate into a virus transmissible between humans and led
to a pandemic.