Manipal College Of Pharmaceutical Sciences, Manipal Academy Of Higher Education, Manipal., India
Background: Vaccine-associated paralytic poliomyelitis (VAPP) is a rare but serious adverse effect of oral poliovirus vaccines. According to the World Health Organization (WHO) in 2002, the estimated worldwide incidence of vaccine-associated paralytic poliomyelitis (VAPP) was between 250 to 500 cases, based on the calculation that 1 VAPP case occurs for every 2 to 4 million births. Studies suggest that Immunodeficient individuals are at high risk of developing VAPP. Furthermore, It is seen in primary vaccine recipients as well as in people who are close contacts of recently vaccinated individuals.
Objectives: We tend to evaluate the relationship between oral poliovirus vaccination and the occurrence of vaccine-associated paralytic poliomyelitis (VAPP) using Vaccine adverse event reporting system (VAERS).
Methods: The methodology utilized in this study involved conducting a disproportionality analysis to investigate the association between VAPP and oral poliovirus vaccination. This study was a post-marketing pharmacovigilance investigation utilizing the VAERS data for the poliovirus vaccine. The adverse events reported to VAERS from its inception to February, 2023 were obtained, with duplicates removed using an Excel database. A disproportionality analysis was performed by constructing a 2x2 contingency table and the Reporting Odds Ratio (ROR) was calculated. To assess the significance of the disproportionality between the vaccine and event combination, a criterion of ROR > 1 and a lower limit of 95% Confidence Interval (CI) > 1 was utilized.
Results: From 1990 to 2023, 251 reports of VAPP were extracted from a total of 5,552,785 adverse event reports related to the Polio vaccine with the prevalence of 0.0045%. The reporting odds ratio was calculated for each year and the association between VAPP and the vaccine was established based on predetermined criteria. 1997 reported the strongest association with the ROR value of 77.39. Significant association has been reported by the calculated ROR data for following 12 years as: 1990(ROR = 4.10),1991(ROR = 32.13),1993(ROR = 6.95),1994(ROR = 4.52), 1995(ROR = 9.08),1997(ROR = 77.39),1998(ROR = 3.76),2018(ROR = 5.94),2020(ROR = 3.20),2021(ROR = 4.77), 2023(ROR = 1.83).
Conclusions: Although VAPP is a rare event, it has the potential to cause life-long complications. Prevention strategies must be implemented to avert VAPP associated complexities. Furthermore, screening for risk factors such as immunodeficiency must be performed prior to vaccinating individuals.
