Bird flu may have infected two more people in Vietnam, where scientists say it has mutated into a more dangerous form which could spread in mammals.
State newspapers reported today that a student was being tested in hospital after eating chicken eggs along with samples from a 78-year-old woman who died from serious pneumonia in the central province of Quang Binh on Friday.
An Agriculture Ministry report said the H5N1 virus had now hit 10 of Vietnam's 64 provinces since returning in early October. Vietnam's death toll since the virus first arrived in late 2003 is 42.
The latest affected area is the northern port of Haiphong where 1,000 ducks and chickens died in four farms last week.
"There is much possibility that the disease spreading is due to improper quarantine of infected poultry and poultry products," the head of the ministry's animal health department said.
Search-and-destroy task force groups must be set up to deal with sick poultry, he said.
The Ho Chi Minh Pasteur Institute said its decoding of 24 samples of the H5N1 virus taken from poultry and humans showed a significant variation of antigen - any foreign substance that stimulates the body's immune system to produce antibodies.
"There has been a mutation allowing the virus to breed effectively on mammal tissue and become highly virulent," it said. The finding showed the virus had been combining changes to adapt to new hosts.
Vietnam is gearing up its battle against bird flu, with Hanoi and Ho Chi Minh City officials spreading the word about a November 15th deadline from when poultry raising will be banned in those cities.
The Hanoi's People Committee said live poultry will be destroyed from Thursday if found in the capital.
Bird flu has killed at least 64 people in Asia since it arrived in 2003 and became endemic in several countries.