Characteristics of adverse events following immunization in Changsha in 2021 / 公共卫生与预防医学

ABSTRACT

Objective To analyze the characteristics of suspected adverse events following immunization (AEFI) in Changsha in 2021. Methods Data on AEFI cases and vaccination doses of all vaccines in 2021 were obtained from the China Information System for Disease Control and Prevention．Descriptive epidemiological methods were used for data analysis. Results A total of 1 658 AEF1 cases were reported in Changsha in 2021. The male to female ratio was 0.801. The ≤1 year old group, 2-6 years old group, and ≥7 years old group accounted for 15.80%, 24.31%, and 59.89%, respectively. Among all AEFIs，common and rare adverse reactions accounted for 85.34% and 2.65% respectively, with reported incidence rates being 4.777 and 0.219 per 100 000 doses，respectively．The total estimated AEFI rate was 7.122 per 100 000 doses. The incidences of severe AEFI and non-serious AEFI were 0.185 and 6.937 per 100 000 doses, respectively. The top five vaccines reported by AEFI were AC meningitis/Hib triple vaccine (574.713 per 100 000 doses, 1 case), measles vaccine (72.836 per 100 000 doses, 62 cases), DTP vaccine (Cell-free) (64.614 per 100 000 doses, 61 cases), freeze-dried live attenuated influenza vaccine (nasal spray) (61.805 per 100 000 doses , 1 case), and herpes zoster vaccine (CHO cells) (54.715 per 100 000 doses , 3 cases). Conclusion The reported incidence of AEFIs decreased slightly in Changsha in 2021．Most adverse reactions were mild，and the incidence of adverse reactions were low.