Analysis on Adverse Events Following Immunization in Hubei Province in 2010

Objective To analyse the occurrence features of adverse events following immunization(AEFI) in Hubei province during 2010, so as to evaluate the operation status of AEFI monitoring system, and the safety of vaccines and vaccination services quality of national immunization programs (NIP). Methods AEFI data were collected through the national information system of AEFI, which reported in Hubei from January 1st to December 31st, 2010. The epidemiological analysis on relevant index was conducted by descriptive methodology. Results The 1,770 cases of AEFI were reported in Hubei, in 2010, with 100% county coverage. The reported rate within 48h was 88.76%, the investigated rate within 48h was 97.74%, and the rate of completed investigation form was 100%. Among 1770 AEFI cases, the sex ratio of male and female was 1.41∶1, and children aged≤2 years accounted for 77.46%. AEFI in the top five vaccines were measles attenuated live vaccine, acellular pertussis, tetanus and diphtheria combined vaccine, diphtheria,tetanus, whole pertussis combined vaccine, group A meningococcal polysaccharide vaccine, and Japanese encephalitis attenuated live vaccine. The occurrence of AEFI after first dose and ≤1 day vaccination accounted for 65.42% and 84.18%, respectively. In AEFIclassification diagnosis, adverse reactions accounted for 96.10%, and other reactions accounted for 3.90%. In a variety of AEFI clinical impairment,allergic reactions, aseptic abscesses and Bacilli Calmette-Guerin vaccine (BCG) lymphadenitis were ranked in the top three. AEFI estimated reporting rate of NIP vaccines in Hubei were 0.28-25.43 per million. Conclusions The integrity and sensitivity of AEFI surveillance in Hubei were improved in 2010 than in the past years. However, AEFI monitoring quality should be improved further. AEFI occurred mainly in younger age groups after NIP vacines with the first dose within 1 day, which indicated that the younger age group is the priority group for monitoring. In addition, AEFI surveillance results showed that NIP vaccines were safety, and there was good service quality of vaccination in Hubei.