Post-marketing observation on safety of inactivated enterovirus A71 vaccine (human diploid cell) / 中华预防医学杂志

Objective@#To evaluate the post-marketing safety of inactivated Enterovirus type 71 (EV-A71) vaccine (human diploid cell) .@*Methods@#A total of 20 191 healthy children aged 6 to 59 months were invited to receive 2 doses of EV-A71 vaccine in Zhejiang Province from September 2016 to December 2017. Child caregivers were followed up on the 4th or 5th day after each EV-A71 vaccination, and the incidence of local, systemic, and other adverse events within 3 days after vaccination was recorded to assess vaccine safety. Describe the differences in adverse events among children with different characteristics.@*Results@#A total of 32 230 doses were observed in this study, of which 20 191 and 12 039 were vaccinated for the first and the second dose, respectively; and the incidence of adverse events within 3 days was 2.045% (413 doses) and 1.611% (194 doses), respectively. After the first and the second dose, the number of systemic adverse events was the highest, 371 and 175 cases, respectively, with an incidence of 1.837% and 1.454%, respectively; the number of local adverse events was the lowest, 14 and 2 doses, respectively, with an incidence of 0.069% and 0.017%. Local adverse events occurred after vaccination were generally mild, and only 2 patients had level of 3; among the systemic adverse events, 39 patients had a fever level of 3 or higher, accounting for 8.2% of the total fever. Most of the symptoms in the local adverse events did not require treatment, only 3 cases of vaccination site rash and 2 cases of pruritus were self-purchased drugs or outpatient treatment; except for 5 cases of fever, the other symptoms were not hospitalized in the case of systemic adverse events.@*Conclusion@#The incidence of adverse events within 3 days after vaccination with EV-A71 vaccine was low in children, mainly systemic adverse events, and the prognosis was good.

Post-marketing safety analysis of inactivated enterovirus A71 vaccines / 中华预防医学杂志

Objectives@#To evaluate the safety of inactivated enterovirus A71(EV-A71) vaccines after large-scale immunization in the community.@*Methods@#We selected EV-A71 susceptible people (healthy children) aged 6-59 months in vaccination clinics from 89 counties in Zhejiang Province between April 2016 and March 2018. All local and systematic adverse actions were collected by 30 min on-site inspection, within 3 days and 4-30 days follow-up. Chi-square test and Fisher′s exact test were used to compare the difference of AEs incidence in various characteristics among two groups.@*Results@#A total of 71 663 doses of vaccines were included for active safety analysis, which included 37 331 doses in boys and 34 332 doses in girls. Among all the doses, children aged 6 to 11 months, 12 to 23 months and 24 to 59 months were received 13 707, 32 639 and 25 317 doses respectively. The incidence of adverse reactions within 30 min, 3 days and 4-30 days were 0.33% (239 doses), 1.58% (1 133 doses) and 0.34% (244 doses) respectively. Adverse reactions within 3 days were 1 372 doses, with a incidence of 1.91%; among all the cases, 539 doses (0.75%) were grade 1, 677 doses (0.94%) were grade 2 and 156 doses (0.22%) were grade 3, no grade-4 adverse reaction was reported. The common local adverse reactions were redness, swelling and pruritus, with the incidence rates were 0.05% (39 doses), 0.02% (16 doses) and 0.02% (12 doses), respectively, while the most common systemic adverse reaction was pyrexia with an incidence of 1.19% (856 doses), followed by diarrhea and anorexia with the incidence rates were 0.15% (104 doses) and 0.13% (90 doses) respectively.@*Conclusion@#Most adverse actions of EV-A71 vaccines were mild and moderate and majority of them were common adverse actions. No new adverse reactions were found in the study.

Surveillance results of adverse events following immunization of enterovirus 71 inactvated vaccine / 预防医学

Objective@#To evaluate the safety of enterovirus 71（EV71）inactivated vaccines produced by Wuhan Institute of Bio Products through learning the incidence of adverse events following immunization（AEFI）in children aged 6 months to 3 years old after vaccination.@*Methods@#According to the national requirement for vaccine safety monitoring program，data of AEFI cases after inoculated EV71 vaccines from September 2017 to October 2018 in Zhejiang Province was collected by combining active and passive monitoring. Demographic characteristics，space distribution，dose and incidence of AEFI were analyzed.@*Results@#A total of 107 503 children were included in this study，of which 27 173 were actively monitored and 80 330 were passively monitored. The monitoring results showed that 288 cases of AEFI occurred after inoculated EV71 vaccines，the reported incidence rate was 267.90/100 000. Of 288 cases，266 cases had common reactions（247.43/100 000），14 cases had abnormal reactions（13.02/100 000）and 8 cases had complications（7.44/100 000）；145 cases were passively monitored（180.51/100 000）and 143 cases were actively monitored（526.26/100 000）；150 cases were males and 138 cases were females，with the males to females ratio of 1.09∶1. The AEFI of EV71 vaccines were reported in all the cities of Zhejiang Province，with Jinhua，Taizhou and Hangzhou ranking the top three and accounting for 50.69% of all the reported cases. About 202 cases of AEFI（70.14%）occurred after the first dose of EV71 vaccines，and 163 cases（56.60%）occurred on the day of inoculation.Most of common reactions were fever，swelling and sclerosis. The harm of the reported abnormal reactions was mild，with 8 cases of anaphylactic rash and no other serious abnormal reactions were found. @*Conclusion@#The reported incidence rate of AEFI of the domestic EV71 vaccine in children aged from 6 months to 3 years is 267.90/100 000，without serious abnormal reactions，suggesting that the EV71 vaccine is safe.