Studies show the H5N1 strain of virus separated from China's
human cases of bird flu has mutated compared with the strain found
in Vietnam's human cases, the Ministry of Health (MOH) said on
Monday.
Lab tests find the H5N1 strain of virus separated from recent
human cases is highly homologous with that found in poultry samples
from the bird flu outbreak places, according to the information
office of the MOH.
However, compared with the virus strain from the human cases in
Vietnam, the genetic order of H5N1 in China's human cases has
mutated "to a certain degree," MOH spokesman Mao Qun'an said.
"But the mutation doesn't necessarily cause human-to-human
transmission of the avian flu," he noted.
Mao said since the H5N1 bird flu first broke out in 1997, most
human cases have been reported in Hong Kong, Thailand, Vietnam,
Cambodia, Indonesia and the Chinese mainland. No human case has
been reported in Europe to date.
The major channels of human infection involve direct contact
with infected poultry or their secretions and excrement, as well as
inhalation of virus particles of the virus from poultry secretions
and excrement, said Mao, noting that infections are rare as long as
people stay away from sick or dead infected poultry.
As of November 25, the World Health Organization (WHO) had
reported 132 confirmed human cases of bird flu including 68
deaths.
China has reported three confirmed human cases of bird flu,
including two fatalities from east China's Anhui Province and one
case from central China's Hunan Province where the patient
recovered.
(Xinhua News Agency November 29, 2005)