Monitoring of adverse reaction of Haemophilus influenzae type b vaccine in Songjiang District， Shanghai / 上海预防医学

ABSTRACT

ObjectiveTo determine the reporting rate of adverse reaction of Haemophilus influenzae type b （Hib） containing vaccine in Songjiang District from 2016 to 2020， so as to provide evidence for the inclusion of Hib vaccine in children's immunization planning and safety monitoring. MethodsThe adverse reaction data of Hib vaccination were collected through the Chinese Disease Prevention and Control Information System and presented by descriptive methods. ResultsFrom 2016 to 2020， the reporting rate of adverse reaction of various Hib-containing vaccines in Songjiang District was determined to be 747.76/105 doses， among which the rates of general reaction and abnormal reaction were 734.31/105 doses and 13.45/105 doses， respectively. The reporting rate of general reaction was significantly higher than that of abnormal reaction （χ2=1 400.18，P<0.001）. Moreover， the reporting rate of adverse reaction did not differ significantly by sex or registered residence， whereas it differed significantly by age groups （χ2=366.07，P<0.001）. Children ≥12 months old had the highest reporting rate， which was caused by higher rate of general reaction （χ2=360.48，P<0.001） compared with other age groups； in contrast， there was no difference in the reporting rate of abnormal reactions across age groups. The reporting rate of adverse reaction differed significantly across four Hib-containing vaccines （χ2=508.51，P<0.001）， among which the reporting rate of pentavalent vaccine was the highest， followed by tetravalent vaccine， and Hib vaccine and meningococcal HI vaccine. This difference was mainly caused by general reaction （χ2=499.19，P<0.001）. The reporting rate of booster Hib-containing vaccines was significantly higher than that of basic immunization （χ2=462.85，P<0.001）. Furthermore， the reporting rate differed between DTaP-Hib vaccine and DTaP-IPV-Hib vaccine by injection sites（χ2=13.63，P=0.001；χ2=78.48， P<0.001）； the reporting rate on the thigh was lower than that on the hip or upper arm. Among the 1 501 reported adverse reactions， 97.21% of the general reactions and 85.19% of the abnormal reactions occurred within 72 hours following immunization. Principal clinical diagnosis was fever， redness and nodules （n=1 454）， accounting for 96.87% of the total reported adverse event following immunization（AEFI）， followed by allergic rash. ConclusionThe four types of Hib-containing vaccines have high safety. Health care practitioners at points of vaccination should improve the pre-examination， standardized operation and full notification in strict accordance with the requirements. It also warrants strengthening the AEFI monitoring， investigation and response， so as to effectively reduce the incidence and severity of adverse reactions.