Knowledge,perceptions,and practice towards adverse events following immunization surveillance among vaccination workers in Zhejiang province,China

Objective:To access the level of knowledge,perceptions,and practice towards adverse events following immunization(AEFI)surveillance among vaccination workers in Zhejiang province,China.Methods:This was a cross-sectional survey involving 768 vaccination workers.Data were collected using self-administered questionnaires and analyzed by using SAS 9.3 software.Knowledge,perceptions,and practice on AEFI surveillance were summarized using frequency tables.The mean±SD value was used as the cut-off for defining good(values≥mean)and poor(values<mean)knowledge,perceptions or practice.Binary logistic regression analysis was used to determine sociodemographic variables associated with knowledge,perceptions,and practice towards AEFI.Results:The proportions of good knowledge,perceptions and practice on AEFI surveillance were 78.13%,57.81%and 66.15%,respectively.Having a higher education background,longer years of experience,previous training on AEFI and≥30 years of age were factors associated with good knowledge,perceptions and practice on AEFI surveillance among vaccination workers.Conclusions:Over half of the respondents had good knowledge,perceptions and practice on AEFI surveillance work.Interventions on improving the vaccination workers’knowledge,perceptions and practice on AEFI surveillance should be considered in order to develop a more effective surveillance system.

A Case of Investigation and Diagnosis of Immune Thrombocytopenic Purpura After Vaccination of COVID-19 Inactivated Vaccine

Objective:Analyze the relationship between inoculating one case of the COVID-19 inactivated vaccine(Vero cell)and immune thrombocytopenic purpura to provide a reference for the standardized handling of adverse events following immunization.Methods:According to the"National Monitoring Program for Suspected Adverse Reactions to Vaccinations,"an on-site investigation,data collection and analysis,expert group diagnosis,and medical association assessment were conducted on a case of immune thrombocytopenic purpura in District A of Chongqing after vaccination with the inactivated COVID-19 vaccine.The assessment report was delivered to the three relevant parties,the case was reviewed,and the experience was summarized.Results:The investigation and diagnosis by the district-level vaccination abnormal reaction expert group concluded that the disease that occurred after vaccination with the COVID-19 inactivated vaccine was secondary immune thrombocytopenic purpura,an abnormal reaction to the vaccination.The medical damage was classified as Level II Grade B.The vaccine production enterprise raised objections to this conclusion.After re-assessment by the municipal-level medical association,the conclusion was consistent with that of the district-level medical association.The vaccine production enterprise did not raise any further objections.Conclusion:Through active collaboration among district and municipal-level medical associations,disease control institutions,and vaccination units,the recipients have been promptly and effectively treated,providing financial support for their subsequent treatment and safeguarding their rights.The investigation and disposal procedures for adverse events following immunization in Chongqing are clear,and the mechanism is sound.It is necessary to continue strengthening the monitoring of adverse events following immunization according to the existing plan and to ensure timely and standardized handling.Simultaneously,it is crucial to strengthen vaccine management and vaccination management.

Hearing loss and tinnitus associated with COVID-19 vaccines:An analysis from the national pharmacovigilance database in Malaysia

Objective:To compare the reporting pattern of hearing loss and tinnitus across different vaccines brands used in Malaysia(BNT162b2,CoronaVac,ChAdOx1,Ad5.CoV2-S and BBIBP-CorV).Methods:This retrospective study included all reports of hearing loss and tinnitus occurring after COVID-19 vaccination that were received in the national pharmacovigilance database,QUEST,from February 24,2021 through July 31,2022.Reports given causality consistent or indeterminate were included.Results:There were 21 cases of hearing loss,with overall reporting rate of 0.29 cases per million doses.The rate was similar across BNT162b2,CoronaVac and ChAdOx1.For tinnitus,35 cases were reported,with the overall reporting rate of 0.49 cases per million doses,and the highest rate was reported for ChAdOx1.For both events,most cases aged 30 to 49 years.No gender disparity was observed.Both events were mainly reported to have occurred after the primary doses,with a median time-to-onset of two days.There were no statistically significant differences in the reporting patterns for both events across BNT162b2,CoronaVac and ChAdOx1 by age group,gender,race,and dose number.Conclusions:Despite the low reporting rates and insufficient evidence to confirm its relationship,hearing loss and tinnitus following vaccinations should not be ignored due to its disabling potential and impact on one’s quality of life.Continual reporting is encouraged for better signal characterization in the future.

中英疫苗采购、配送及监测比较

目的比较中英两国的免疫接种系统及工作程序,以期为我国免疫接种工作提供借鉴和启示。方法通过文献回顾和网站信息收集,系统梳理中英两国疫苗采购、配送和异常反应监测的相关政策、文件、新技术应用等信息。结果在疫苗采购方面,两国纳入国家免疫规划的疫苗均由政府统一采购、免费接种,且中国实行强制接种政策。在疫苗配送方面:英国全境的疫苗由1家物流公司统一配送,配送费用由政府支付;我国各省(自治区、直辖市)的疫苗配送情况不一,多由当地疾病预防控制机构负责配送。在预防接种异常反应监测方面,英国疫苗上市后的异常反应监测系统和相应的赔偿制度较为成熟,我国的相关系统和制度还有待完善。结论针对现存的问题,我国应聚焦疫苗的生产源头、流通运输和安全监测,提高疫苗生产企业的准入门槛,大力发展我国医药冷链物流业,逐步完善我国疫苗预防接种异常反应监测系统。

Safety of SARS-CoV-2 vaccines:a systematic review and meta-analysis of randomized controlled trials

Background Various modalities of vaccines against coronavirus disease 2019(COVID-19),based on different platforms and immunization procedures,have been successively approved for marketing worldwide.A comprehensive review for clinical trials assessing the safety of COVID-19 vaccines is urgently needed to make an accurate judgment for mass vaccination.Main text A systematic review and meta-analysis was conducted to determine the safety of COVID-19 vaccine candidates in randomized controlled trials(RCTs).Data search was performed in PubMed,Embase,Cochrane library,Scopus,Web of Science,and MedRxiv.Included articles were limited to RCTs on COVID-19 vaccines.A total of 73,633 subjects from 14 articles were included to compare the risks of adverse events following immunization(AEFI)after vaccinating different COVID-19 vaccines.Pooled risk ratios(RR)of total AEFI for inactivated vaccine,viral-vectored vaccine,and mRNA vaccine were 1.34[95%confidence interval(CI)1.11–1.61,P<0.001],1.65(95%CI 1.31–2.07,P<0.001),and 2.01(95%CI 1.78–2.26,P<0.001),respectively.No significant differences on local and systemic AEFI were found between the first dose and second dose.In addition,people aged≤55 years were at significantly higher risk of AEFI than people aged≥56 years,with a pooled RR of 1.25(95%CI 1.15–1.35,P<0.001).Conclusions The safety and tolerance of current COVID-19 vaccine candidates are acceptable for mass vaccination,with inactivated COVID-19 vaccines candidates having the lowest reported AEFI.Long-term surveillance of vaccine safety is required,especially among elderly people with underlying medical conditions.