Epidemiological Insights and Vaccine Utilization Patterns: A Retrospective Record Review of Yellow Fever Vaccination in Eastern India (2016-2022)

Utilisation and wastage of yellow fever vaccine in Eastern India

Abstract

Background: The yellow fever disease, an acute viral haemorrhagic illness caused by mosquitoes, is characterised by great outbreak potential, high mortality rates, and is predominantly encountered in Africa. Vaccination against yellow fever disease constitutes the cornerstone for disease control, with several countries mandating vaccination of travellers for entry. Objective: This study aimed to determine the epidemiological profile and estimate the vaccine usage and wastage rates at a designated yellow fever vaccination centre at a tertiary care institution in Eastern India. Methods: A retrospective record-based secondary analysis of the data on yellow fever vaccine recipients from 2016 and 2022 was performed. Findings: From 2016 to 2022, 19,581 individuals received the yellow fever vaccine. The majority (79.6%) were aged between 21-40 years, and 96.0% of the recipients were male. Hindus comprised the largest religious group (83.5%), and about two-thirds (66.1%) of the recipients hailed from Bihar. Africa was the most common destination (84.3%) among the vaccine recipients. Usage rates increased from 95.56% in 2016 to 100% in 2022, with a concomitant decline in wastage rates from 4.44% to 0%. Two-dose vaccine vials were the ones used most frequently (64.47%), and over four-fifths (81.97%) of the vaccine doses wasted originated from a two-dose vial. Conclusion: The study showcased a declining trend in vaccine wastage rates. Use of smaller vaccine vials will help minimise wastage and promote effective utilisation of the vaccine.