Time-to-event analysis of COVID-19 precautionary dose vaccination among healthcare workers in a teaching institute of a metropolitan city in India, using Co-WIN data.

Abstract

Vaccination emerged as a significant and critical intervention for tackling the Covid-19 pandemic. During vaccine introduction in India, healthcare and front-line workers were prioritized to receive the vaccine first. This study aims to analyze the uptake patterns of precautionary doses among HCWs for Covishield and Covaxin vaccines using time-to-event analysis. Retrospective Observational study. Covid Vaccination center at a teaching institute in Mumbai. Healthcare Workers (HCWs) who received precautionary doses of Covishield or Covaxin between January 10, 2022, and July 6, 2022, at the Covid vaccination center in a teaching institute in Mumbai. 2,615 HCWs received Covishield and 93 received Covaxin precautionary doses. For Covishield, 86.5% took the precautionary dose within two weeks, with a mean uptake time of 9.1 days. Younger age groups and females showed higher uptake times. For Covaxin, 57% took the precautionary dose within two weeks, with a mean uptake time of 32.98 days. Younger age groups had higher uptake times, while females had lower uptake times for the precautionary dose. Cox regression identified younger age as a significant predictor of delayed uptake for Covishield. HCWs showed good overall acceptance of precautionary doses, with improved uptake compared to initial doses. Females and younger age groups generally had longer uptake times. These findings highlight the need for targeted education and risk communication strategies to ensure timely vaccination among HCWs. The study also highlights the value of having good data stored in vaccination platforms, analyzed, and interpreted for informed decision-making in future health campaigns.