Quinvaxem is a preventative inoculation against diphtheria, tetanus, pertussis or whooping cough, hepatitis B and H and influenza Type B.
According to Xinhua, Quinvaxem is manufactured by the Berna Biotech Korea Corporation and was licensed for use in Vietnam's immunisation programme sponsored by the Global Alliance for Vaccines and Immunization.
Since June 2010, Vietnam has imported 16.2 million doses of Quinvaxem, 15.2 million doses of which have already been distributed, state-run Voice of Vietnam reported.
The WHO has sent experts to Vietnam to investigate the alleged side-effects of Quinvaxem.
Batches of Quinvaxem have also been sent to Britain for tests.