The Assessment Of National AEFI Information Management System And Analysis On Adverse Events Following Immunization Surveillance In China,2005-2012

BackgroundWith the concerns of vaccine safety increasing gradually, AEFI surveillance played a vital role in maintaining vaccination. Since2005, vaccine safety in China is monitored continually. But there was less assessments of the quality of AEFI surveillance system, and analysis of the AEFI records in China, in a manner of several years as a whole. Analysing trends in passive reports can identify signals or assist in generating hypotheses that can then be tested by more rigorous methods.ObjectivesThis study focuses on AEFI reported for vaccines administered from2005to2012, and on the trends in AEFI reporting for the8-year period. The objectives of this study is to assess the implementation quality of national AEFI information management system, to analyze the features of AEFI in China (not include Hong Kong Administrative Region, Macao Special Administrative Region and Taiwan sheng), and to get the estimated rate of AEFI for common-used vaccines,2005-2012.MethodsThis report summarised national passive surveillance data for AEFI reported to the national AEFI information management system from2005to2012. The descriptive methodology was used in this study. Using vaccination doses collected from Chinese immunization information system of2005-2012as the denominator.Results1Assessment of national AEFI information management systemSince2005,provinces of reporting AEFI cases increased from10to all provinces, with reporting counties increased from401(14.01%) of2005to2827(99.12%) of2012,including the proportion of counties with reporting in east and middle area reached100.00%. The total number of AEFI cases increased from1932of2005to105,498of2012. Proportion of cases reported within48h was increase from76.09%of2005to98.42%of2012,and that of investigation was86.28%to99.17%. The mistakes of completeness and correctness of AEFI cases was<1%, and the proportion of AEFI with classification was>90%.2Features of AEFI recordsA total of318,412cases were collected during2005to2012. Cases≤1year old accounted for69.29%,and the ratio of male-female was1.39:1.55.47%of AEFI occurred after the first dose and mainly within the first day after immunization.3Estimated incidence rate of AEFIThe NIP vaccines that ranked the first3places of estimated common vaccine reactions incidence rate was:Diaphtheria,Tetanus and Pertussis Combined Vaccine(DTP) of22.15per million doses, Diphtheria and Tetanus Combined Vaccine(TD) of16.23per million doses, and Measles and Rubella Combined Attenuated Live Vaccine(MR) of13.35per million doses. The NIP vaccines that ranked the first3places of estimated rare vaccine reactions incidence rate was:MR of4.03per million doses, Bacilli Calmette-Gu6rin Vaccine(BCG) of2.97per million doses, and Measles,Mumps Combined Attenuated Live Vaccine(MM) of2.90per million doses. Fever, redness and swelling accounted for most common vaccine reactions and rash accounted for most rare vaccine reactions.Conclusion1The implementation quality of national AEFI information management system was improving gradually through the8years, which can provide a relatively solid foundation for data analysis in the furture.2AEFI cases were mainly common vaccine reactions and rash accounted for most rare vaccine reactions.3. Compared with the WHO reference incidence rate,the AEFI incidence rate of China was within a safe range.4More increases of incidence rate were detected in this study, except the HepA-L.Innovation1The implementation quality of national AEFI information management system was assessed8years in a whole for the first time.2A continuous analysis of AEFIs in China from2005to2012was made for the first time, and provided a baseline incidence data of AEFI and adverse reactions for common-used vaccines.3Set a distributed dose database of2007-2012and set a database of administered doses of vaccines from2005-2012.4In addition to dealed safety signals with HepA-L, VarV, more detection of increasing rate of systemic, local reactions, or the main adverse reactions was found in this study. All these could provide a realistic value for future work.Limitations1The results of this study can only provide some increased incidence for part of the vaccines used in China, less further investigation was made in this study.2The distributed doses of vaccines of non-NIP was used as the denominator in this study since we failed to obtain the actual administered doses of vaccines.