Analysis of death cases in Shenyang City, China, for immunization adverse event surveillance, 2009-2021

Through the Chinese National Immunization Adverse Event Surveillance System (CNAEFIS), we collected reports of Adverse Event Following Immunization (AEFI) deaths in Shenyang from 2009 to 2021 with the aim of analyzing AEFI-related deaths and assessing the safety of vaccination. From 2009 to 2021, a total of 12 AEFI-related deaths were reported in Shenyang City, and autopsies were performed in 6 deaths. According to the assessment of the Expert Committee on Investigation and Diagnosis of AEFI 3 (25.0%) deaths were classified as severe vaccine reactions, 9 (75.0%) deaths were classified as coincidental events, and there were no immunization errors or psychological reactions. The overall estimated AEFI-related mortality rate was 0.12 per 100,000 vaccination doses. Spearman's rank correlation analysis showed no correlation between AEFI, severe vaccine reactions, and suspected vaccination-related deaths. Coincidental events are the most common type of death following vaccination, meaning that the risk of death following immunization is low, and ongoing AEFI surveillance and scientific causality assessment are essential to ensure the vaccine confidence. Detailed pre-vaccination health status questioning is also key to avoiding and reducing adverse events.

Adverse Events Following Immunization Among Children Under Two Years of Age: A Prospective Observational Study From North India

BACKGROUND

Vaccination is one of the most cost-effective child survival health interventions. A single serious adverse event following immunization (AEFI) or a cluster of events may lead to a loss of public confidence in the program and a major setback to immunization coverage. This study was conducted to assess the incidence of AEFIs in children less than two years of age.

MATERIAL AND METHODS

A prospective community-based observational study was conducted in the North Indian state of Uttarakhand from October 2017 to February 2018. A total of 255 children who attended the selected sub-centres for immunization were finally included in the study. Follow-up home visits on the 8th and 30th day of vaccination were carried out to identify any occurrences of AEFIs.

RESULTS

Among 255 children, 212 AEFIs from 152 vaccinated subjects were reported. The majority of the AEFIs were reported in the age group 0-1 years. The incidence of AEFIs was 33.0 per 100 doses of vaccines administered. The most common AEFI reported was fever (101, 47.6%), followed by swelling (53, 25.0%). Among the vaccines, Pentavalent + oral polio vaccine (OPV) (48.8 per 100 doses) was majorly responsible for AEFIs, followed by diphtheria pertussis tetanus (DPT) + measles and rubella (MR) + OPV (46.6 per 100 doses).

CONCLUSION

Our findings revealed that although the incidence of AEFI reported was high, all of them were minor and no serious AEFIs were identified. The awareness among health professionals and the public regarding the reporting of AEFIs should be continued to increase the safety profile of vaccines.

Barriers to healthcare workers reporting adverse events following immunization in Zhejiang province, China

Objectives

A cross-sectional survey was conducted among healthcare workers (HCWs) to assess their knowledge, attitude, and reporting behavior in adverse event following immunization (AEFI) surveillance as well as to identify barriers.

Methods

A simple random sample of 170 vaccination clinics was selected and one HCW was informed to participate in this survey in each selected vaccination clinic. The survey was developed using a secure online platform and consisted of a structured online questionnaire. The distributions of the respondents’ characteristics were presented. Training status, knowledge, attitude, and reporting behavior were compared between sub-groups of HCWs. Barriers and suggestions on AEFI reporting were also summarized.

Results

Of the 170 surveyed HCWs, 61.76% received the training on AEFI surveillance while 15.88% had no AEFI training at all. The higher level of knowledge and the more positive attitude and reporting behavior on AEFI surveillance were observed among HCWs with the longer working duration on AEFI surveillance, or among HCWs who received the training. The most critical barrier to reporting an AEFI was ‘not being sure if the AEFI is related to the vaccine’ (122, 71.76%). Other barriers were: ‘I do not want to raise unnecessary public alarm about a vaccine’ (105, 61.76%); ‘reporting form or other method being too complicated’ (65, 38.23%).

Conclusion

The study findings highlighted the need to prioritize training on AEFI surveillance for HCWs. It is recommended that the development of the targeted interventions to strengthen AEFI surveillance system be required based on the barriers found in this study.

A Comparison with Adverse Events Following Immunization Associated with Sabin-Strains and Salk-Strains Inactivated Polio Vaccines in Zhejiang Province, China

Objectives: One dose of Sabin-strains inactivated polio vaccine (IPV) was introduced into the Chinese immunization program on 1 May 2016. This study aimed to evaluate the safety of Sabin-strains IPV and provide a comparison with conventional Salk-strains IPV. Methods: Adverse events following immunization (AEFI) records associated with Sabin-strains IPV and Salk-strains IPV were extracted from the national AEFI surveillance system (NAEFISS) from 1 May 2016 to 31 December 2020. The vaccination information on Sabin-strains IPV and Salk-strains IPV during the same period was obtained from the Zhejiang provincial immunization information system. Reporting rates of AEFI were calculated by age, city, severity of AEFI, categories of AEFI, and reaction categories and were compared between Sabin-strains IPV and Salk-strains IPV. Results: In total, 3,861,758 doses of Sabin-strains IPV and 1,018,604 doses of Salk-strains IPV were administered during the study period. The overall AEFI reporting rate for Sabin-strains IPV (3.96/10,000 doses) was significantly lower than that for Salk-strains IPV (5.03/10,000 doses) due to the reporting rate of the minor vaccine product-related reaction following Sabin-strains IPV was significantly lower than that for Salk-strains IPV (2.76/10,000 doses vs. 3.83/10,000 doses). The most frequently reported symptoms/signs were fever, induration/swelling, and rash/urticaria. The most frequently reported serious AEFI with a causal relationship was febrile convulsion, with the reporting rates of 0.10/10,000 doses for Sabin-strains IPV and 0.08/10,000 doses for Salk-strains IPV. No significant difference was found in the reporting rates of the other serious AEFI between the two types of IPV. Conclusion: Most of the AEFI following Sabin-strains IPV and Salk-strains IPV were mild and common adverse reactions. The reporting rate of serious AEFI was not significantly different between Sabin-strains IPV and Salk-strains IPV. Sabin-strains IPV had a favorable safety profile and could be widely used.

How were DTP-related adverse events reduced after the introduction of an acellular pertussis vaccine in Chile?

Chile has a passive surveillance system of adverse events following immunization (AEFI) that allows monitoring and evaluating the safety profile of the vaccines administered. Between 2018 and 2019, the National Immunization Program (NIP) changed from a pentavalent whole-cell pertussis vaccine (wP) to a hexavalent (DTaP-IPV-HepB-Hib) acellular pertussis vaccine (aP) for children <2 years.

Surveillance of adverse events following the introduction of inactivated poliovirus vaccine made from Sabin strains (sIPV) to the Chinese EPI and a comparison with adverse events following inactivated poliovirus vaccine made from wild strains (wIPV) in Jiangsu, China

One dose of inactivated poliovirus vaccine (IPV) was introduced into the Chinese Expanded Program on Immunization (EPI) in 2016. IPV made from Sabin strains (sIPV) was newly licensed in China and its safety has been concerned. This study aimed to evaluate the safety of sIPV and provide a comparison with conventional IPV made from wild strains (wIPV). We collected all IPV-related AEFI reports in Jiangsu from the Chinese National Adverse Events Following Immunization Information System (CNAEFIS) for 2016-2019. We obtained the administered doses of IPV from the Jiangsu provincial Electronic Immunization Registries System (JSEIRS). The AEFI reporting rates per 100,000 doses of vaccine administered were compared for sIPV and wIPV. A total of 699 sIPV and 908 wIPV AEFI cases were collected by CNAEFIS in Jiangsu during 2016-2019. The overall AEFI reporting rates were 53.02 per 100,000 doses and 41.25 per 100,000 doses for sIPV and wIPV, respectively (P < .001). For both sIPV and wIPV, the AEFIs were mainly classified as common adverse reactions. The reporting rate of common adverse reactions was higher for sIPV than for wIPV (P < .001). The most frequently reported symptoms/signs were fever, persistent crying, injection site erythema/swelling, rash, and injection site induration. Only 1.14% of sIPV-associated and 2.31% of wIPV-associated AEFI cases were diagnosed as serious. No difference in reporting rate was observed for serious AEFIs (P = .272). sIPV has a favorable safety profile, although it exhibits a slightly higher reporting rate of common adverse reactions than wIPV.

Knowledge, Attitudes, and Practices (KAP) toward the COVID-19 Vaccine in Oman: A Pre-Campaign Cross-Sectional Study

Oman is globally acknowledged for its well-structured immunization program with high vaccination coverage. The massive spread of misinformation brought on by the COVID-19 pandemic, as well as the easy access to various media channels, may affect acceptance of a vaccine, despite the inherent trust in the local system. This cross-sectional study evaluated the knowledge, attitudes, and practice (KAP) in Oman toward COVID-19 vaccines. It included 3000 randomly selected adults answering a structured questionnaire via telephone. Participants were 66.7% Omani, 76% male, and 83.7% without comorbidities. Their mean age was 38.27 years (SD ± 10.45). Knowledge of COVID-19′s symptoms, mode of transmission, and attitudes toward the disease was adequate; 88.4% had heard of the vaccine, 59.3% would advise others to take it, 56.8% would take it themselves, and 47.5% would take a second dose. Males (CI = 2.37, OR = (2.00–2.81)) and Omani (CI = 1.956, OR = (4.595–2.397)) were more willing to be vaccinated. The history of chronic disease, source of vaccine knowledge, and education level were factors that affected the willingness to accept the vaccine. The Omani community’s willingness to take the COVID-19 vaccine can be enhanced by utilizing social media and community influencers to spread awareness about the vaccine’s safety and efficacy.

The Spectrum of Bacille Calmette-Guérin Diseases in Children-A Decade of Data from Neonatal Vaccination Settings

In this paper, we present a multicentre record-based descriptive study used to estimate the incidence and characterize the spectrum of confirmed bacille Calmette–Guérin (BCG) vaccine-related disease among children in Oman. This study included all children (age ≤ 14 years) who had culture and/or polymerase chain reaction (PCR)-confirmed BCG disease from January 2006 to December 2018, as identified from Central Public Health Laboratory data and International Classification of Diseases coding of an electronic patient information system. In total, 88 children confirmed to have BCG disease were included in the study, making an average incidence of 9.2 cases per 100,000 vaccinated neonates. The males comprised 65.9%, Omanis 93.2%, and the median age of presentation was 4 months in children with BCG disease. The most common type of disease was BCG abscesses (72.4%). Children with immunodeficiency and those presenting within 6 months were found to have a more severe and disseminated disease. In total, 28 children had immunodeficiency. The age of presentation and type of BCG disease was significantly associated with immunodeficiency status. The majority of cases required therapy (both medical and surgical) and recovered well. The incidence of laboratory-confirmed BCG vaccine-related disease was low in Oman supporting continuing the use of the BCG vaccination practice at birth.