ABSTRACT
Objective@#To monitor the adverse events following immunization (AEFI) with combined attenuated live measles, mumps and rubella vaccines (MMR) in Huzhou City from 2015 to 2021, so as to provide insights into the implementation of the MMR immunization strategy.@*Methods@#All AEFI caused by MMR immunization in Huzhou City from 2015 to 2021 were captured from the AEFI Monitoring Information Management System of the Immunization Planning System of Chinese Disease Control and Prevention Information System, and the incidence, clinical features and epidemiological features of AEFI were analyzed descriptively.@*Results@#The reported incidence of AEFI caused by MMR immunization appeared a tendency towards a rise in Huzhou City from 2015 to 2021 (χ2trend=124.126, P<0.001). Totally 324 386 doses of MMR vaccines were immunized, and 317 cases with AEFI were reported, with an reported incidence rate of 9.77/104 doses. Following two-dose immunization, the reported incidence of AEFI caused by two-dose MMR immunization was significantly lower than by one-dose immunization (6.01/104 doses vs. 25.43/104 doses; χ2=113.692, P<0.001). The incidence rates of general reactions, abnormal reactions and coincidental events were 6.20/104 doses, 3.42/104 dose and 0.15/104 doses, respectively. Fever and allergic rash were predominant clinical manifestations of AEFI, and no vaccine quality accident, inoculation accident or psychogenic reaction were reported. There were 246 (77.60%) cases with AEFI within 24 hours following vaccination, and among children with AEFI, there were 173 boys (54.57%), and 200 children (63.09%) age ages of less than one year (63.09%). AEFI was reported in each quarter, and 99 cases (31.23%) were reported in the fourth quarter. The largest number of children with AEFI was reported in Wuxing District (78 cases, 24.61%).@*Conclusions@#The safety of MMR vaccination is high in Huzhou City. General reaction is the predominant AEFI, which mainly occurs within 24 hours following vaccination. Two-dose MMR vaccination does not increase the risk of AEFI.
ABSTRACT
Objective @#To assess the impact of inclusion of hepatitis A vaccine in Expanded Program on Immunization（EPI）on hepatitis A incidence. @*Methods @#The data of patients with hepatitis A from 1998 to 2017 in Huzhou were collected through Huzhou Infectious Diseases Yearbook and China Disease Prevention and Control Information System. Interrupted time-series models were constructed using the year 2008 when hepatitis A vaccine was included in EPI as the intervention time point. The influence of hepatitis A vaccine into EPI on the hepatitis A incidence was evaluated by analyzing the changes in the level and slope of incidence before and after hepatitis A vaccine into EPI. @*Results @#Before the inclusion of hepatitis A vaccine in EPI,the average annual incidence rate of hepatitis A was 10.228/100 000 and the incidence of hepatitis A showed a significant descending trend with an annual decrement of 1.558/100 000. After the inclusion of hepatitis A vaccine in EPI,the average annual incidence rate of hepatitis A was 1.721/100 000 and the incidence of hepatitis A showed a significant descending trend with an annual decrement of 0.263/100 000. The average annual rate of decline in the hepatitis A incidence decreased by 1.295/100 000 after the inclusion of hepatitis A vaccine in EPI. @*Conclusion @#The incidence of hepatitis A significantly reduced after inclusion of hepatitis A vaccine in EPI,and the EPI strategy had a continuous effect on the decreasing trend of hepatitis A incidence.