Vietnam has started the second stage of human trials of an indigenous bird-flu vaccine, testing its immunization effect.
A statement from the Khanh Hoa Province health department said it is cooperating with the Central Institute of Hygiene and Epidemiology to test the vaccine against the H5N1 virus strain of influenza A on 300 locals aged between 18 and 60.
Each will get two shot 21 days apart before undergoing six blood tests to check how they are protected and decide the optimal dose. The virus has an incubation period of 21 days.
The IVACFLU-H5N1 vaccine was created by the Institute of Vaccine and Medical Biologicals (IVAC) based in the central province's capital town of Nha Trang with support from the World Health Organization.
The first stage of human trials was done successfully on 75 people in April 2015.
There will be further tests before the vaccine is licensed for commercial production.
WHO reported 650 human infections of the highly pathogenic H5N1 virus in 15 countries since it recurred in 2003. Around 60 percent died, including at least 65 in Vietnam, which has had one of the highest fatality rates in the world.
Experts from the vaccine institute said only a small number of producers are making bird flu vaccines and at a price not affordable to low- and middle-income countries.
So the low-cost Vietnamese product would be of vital importance, they added.