Investigation of adverse events following Euvax B (hepatitis B) vaccination, May-July 2007
Synopsis and final outcome
From May to July 2007, WHO assisted the government of Viet Nam in the investigation of four serious adverse events (including three deaths) in infants following administration of Euvax B (hepatitis B) vaccine. As a precautionary measure pending investigation of the reported cases, the Department of Immunization, Vaccines and Biologicals (IVB) at WHO recommended on 15 May the temporary suspension of the distribution and use of specific lots of Euvax B vaccine and provided guidance for parallel actions to be taken at country level. Following investigation of the reported cases from Viet Nam and additional reports from other countries as well as vaccine quality testing and a review of the batch records and manufacturing and quality control process at the manufacturing site, no evidence of a quality problem with the vaccine was found. Consequently, on 7 July 2007, WHO removed its recommendation for temporary suspension of specific lots of Euvax B vaccine and recommended that all lots of Euvax B under temporary suspension be released for use. At no time during the investigation was Euvax B vaccine removed from the WHO list of prequalified vaccines.