[Surveillance of adverse events following immunization in Minhang district of Shanghai from 2007 to 2010].

Objective: To analyze the adverse events following immunization (AEFI) in Minhang District of Shanghai from 2007 to 2010 and evaluate the safety of vaccines.

Method: The data of AEFI cases were collected and reported by the Vaccine Adverse Events Surveillance System (VAESS). The data were classified as non-serious or serious reaction according to the symptoms and medical records.

Result: From 2007 to 2010, 5088 AEFI cases were reported to the surveillance system after 4.85 million doses of 24 kinds of vaccines (viral vaccines, bacterial vaccine and non-vaccine product) use. A total of 5013 non-serious AEFI were reported with a rate of 103.24/100 000 doses. Among the non-serious AEFIs, the majority were fever (3314 cases, 68.25/100 000 doses), followed by local reactions (1686 cases, 34.72/100 000 doses). A total of 75 serious AEFIs were reported, with a rate of 1.54/100 000 doses. The anaphylaxis (26 cases, 0.54/100 000 doses) accounted for the most among the serious AEFIs, followed by allergic rash (24 cases, 0.49/100 000 doses) and abscess at injection site (14 cases, 0.29/100 000 doses). The susceptibility of data on AEFI rose year by year from 2007 to 2010, and the reported rate rose from 40.48/100 000 in 2007 to 134.17/100 000 in 2010.

Conclusion: To maintain the sensitivity of AEFI surveillance is key to detect rare serious adverse events. The sensitivity should be enhanced, at the same time, pediatricians should treat the AEFI with standard methods, so as to minimize the negative impacts of vaccination and to maintain the confidence among the public.