Investigation of Death Fetus in Utero after Pandemic Influenza Vaccination, Lamae District, Chumpon Province, Thailand, February 2010

Abstract

During 4-14 February 2010, the Surveillance and Rapid Response Team (SRRT) of Chumphon and Langsuan jointly investigated the cause of fetal death in utero following influenza A H1N1 vaccination in a pregnant woman who lived in Lamae District, Chumphon Province. The objectives were to define cause of fetal death and recommend an appropriate measure for improving vaccination service. Descriptive study, laboratory investigation and documents review obtained from an expert group for adverse event following immunization were done. The fetus was reported dead on 27th week of pregnancy. This pregnancy was a primigravida and the mother received antenatal care (ANC) as scheduled. No abnormal finding was reported at ANC. However, the lab test yielded positive Ig-M for Herpes Simplex. The expert review identified high grade fever in mother a possible cause of fetal death. However, the fever that presented on Day 4 after vaccination was probably caused by other infections. The conclusion was no association between the fetal death and receiving pandemic influenza vaccine. Chumphon provincial health office revised the influenza vaccination program by providing information on benefits and common symptoms following influenza vaccination to pregnant women. If available, an obstetrician gives advice to pregnant women before receiving vaccination. Every hospital must follow up on symptoms of vaccines that may occur after immunization and the data collected will be used for program decision making.