According to the Department of Animal Health, the most recent infections were found in H5N1 is Ha Tinh Province. The virus killed 600 birds in Ky Trinh and 650 birds in Cam Due communes. In the entire 10 provinces affected around 18,000 birds were reported to have died of the disease, 80% of which were ducks.
The mutation of the virus this year shows signs of resistance to the vaccine currently in use for H5N1, called Re-5, created in China.
Scientists confirmed that virus found in northern, central regions, as well as in the highlands is clade 2.3.2. Two sub-mutations have also been identified. These are 2.3.2-A and 2.3.2-B. The current vaccine being used, Re-5, only has 70% protection rate against 2.3.2-A and none at all over the other.
In the south, the bird flu is mostly the old strand of virus, so can be contained with the current vaccines.
The Ministry of Agriculture and Rural Development (MARD) gained approval from Prime Minister to discontinue phase 1 of the 2011 vaccination programme (except in 13 southern provinces) because of its low rate of protection.
Still, some localities insist that Re-5 could help protect poultry in the area. Nguyen Duc Trong, Director of Duck Breeding and Research Center - Dai Xuyen, under National Institute of Animal Husbandry said the protection rate after vaccination is up to 95%-100%.
The Head of Bac Giang Department of Animal Health said that only unvaccinated farms have seen problems.
On February 15, MARD informed it is going to import 80 million doses of Re-5 vaccine in order to prevent a spread of the flu.
Currently, the Department of Animal Health sent 28 virus samples to South Korea to examine the genetic code of the new virus to gain information as to exactly how it is mutating. Results of these tests are expected by this weekend.
The H5N1 virus has killed two people so far this year, making a total of 61 deaths and 119 infections since its appear in 2003.