BACKGROUND

Influenza in India is increasingly shifting from seasonal outbreaks to an endemic presence with potential pandemic risks. Despite ongoing surveillance to monitor regional virus circulation, it's crucial to assess the unique socio-economic impact of influenza compared to other respiratory illnesses.

METHODOLOGY

A retrospective study was conducted from October 2023 to October 2024, analysed 3 years of data from a south Indian tertiary care hospital. Children hospitalised with any subtypes of influenza infection were classified as Group 1, while those vaccinated with at least one dose of influenza vaccine from the hospital's immunisation centre formed Group 2. Trends in infection burden and vaccine utilization among paediatric population were detailed, with separate calculations of the economic burden for each group, leading to a summarized cost-benefit analysis.

RESULTS

Over three-years, Group 1 included 93 children were with a confirmed positive influenza test, while Group 2 consisted of 453 children who received at least one influenza vaccine at the study site. Hence the study site marked an influenza infection rate of 13.62% and a vaccination rate of 6.93%. Infections were more frequent in children over 1 year (74.19%), while vaccine utilization was highest in those under one (91.83%). Boys had a higher infection rate (65.59%) and demonstrated greater vaccine utilization (56.51%). Vaccine underutilization was evident, with only 1.99% receiving timely boosters, and 23.84% missing them. Infections were more prevalent among middle and lower-income children (86.02%), while vaccination rate was higher in upper income families (81.01%). Vaccination cost was 7.76 times lower than treatment; averaging INR 3252.21 (38.73 USD) per child, compared to treatment at INR 25 237.1 (300.14 USD). Net benefit ranged from INR 611 658.99 to INR 1 135 938.12, based on ±30% wage variations within the study community.

CONCLUSION

The study underscores the economic benefits of influenza vaccination; with costs nearly eight times lower than treatment. However, socio-economic disparities in vaccine utilization emphasize the need for targeted strategies to improve access in lower-income groups.