O-20 Survival of COVID-19 cases after vaccination: Analysis using data from Jamaica’s National Surveillance System
Author(s):
K Webster-Kerr, A Grant, A Harris, E Campbell, M Brown, D Rowe, D Henningham, C Lord, R Thorpe, T Mullings, J Wiggan, N Martin-Chen, T DawkinsBeharie, J Azille-Lewis, T Roberts, J Duncan
Year of Presentation:
2023
Objective: To estimate (i) survival after SARS-CoV-2 infection by COVID-19 vaccination status, and (ii) COVID19 vaccine effectiveness in a middle-income country.
Methods: Secondary analysis of data from the national surveillance and vaccination databases was conducted. A total of 1,582 vaccinated cases were compared with 44,196 unvaccinated cases. The primary outcome was COVID-19 death classified based on WHO criteria. Data were analyzed by vaccination status, age, sex, geographic region and wave period. Kaplan-Meier curves were plotted; log-rank followed by multiple comparison tests were used to compare survival probabilities. Cox proportional-hazards models estimated hazard ratios (HR). Vaccine effectiveness was computed as (1-HR)*100%.
Results: There were 23 (1.2%) deaths among COVID-19 vaccinated and 1,821 (98.8%) deaths among unvaccinated cases after follow-up of 327 days. Survival was greater in vaccinated versus unvaccinated cases even after stratification by demographic characteristics (p 0.05) but significant differences were observed among unvaccinated cases (p <0.001). After adjustment for age, sex, and geographic region, the effectiveness against COVID-19 death across all vaccine types (ChAdOx1 nCoV-19, BNT162b2, Ad26. COV2.S or BBIBP-CorV) was 69% (95%CI: 53–79). Effectiveness was 77% (95%CI: 62–86) for ChAdOx1 nCoV-19.
Conclusion: COVID-19 vaccines were effective in preventing COVID-19 death in a population with low vaccination coverage.