Effectiveness of four vaccines in preventing Sars-CoV-2 infection in Almaty, Kazakhstan in 2021
Retrospective population-based cohort study
Bibliographic Data
| ID | 22085492 |
|---|---|
| Authors | Dilyara Nabirova (0000-0002-0314-2202, Centers for Disease Control and Prevention, corresponding author), Roberta Horth (0000-0003-1810-2542, Centers for Disease Control and Prevention), Manar Smagul (0000-0003-0905-8121), Gaukhar Nukenova (0000-0002-6661-0392), Aizhan Yesmagambetova (Ministry of Health of the Republic of Kazakhstan), Daniel Singer (0000-0001-5479-2806, Centers for Disease Control and Prevention), Alden Henderson (0000-0002-0707-1093, Centers for Disease Control and Prevention), Alexey Tsoy |
| Year | 2023 |
| Volume | 11 |
| Pages | 1205159-1205159 |
| Publication date | 2023-06-07 |
| Peer Reviewed | Yes |
| Open Access | Yes |
| Type | ARTICLE |
| Venue | Frontiers in Public Health (JOURNAL) |
| Journal identifiers | ISSN: 2296-2565 • E-ISSN: 2296-2565 |
| Publisher | Frontiers Media SA (PUBLISHER • CH) |
| DOI | 10.3389/fpubh.2023.1205159 |
| PMID | 37351091 |
| OpenAlex | W4379797403 |
| Language | EN |
| Citations received | 2 |
| References cited | 22 |
Background In February 2021 Kazakhstan began offering COVID-19 vaccines to adults. Breakthrough SARS-CoV-2 infections raised concerns about real-world vaccine effectiveness. We aimed to evaluate effectiveness of four vaccines against SARS-CoV-2 infection. Methods We conducted a retrospective cohort analysis among adults in Almaty using aggregated vaccination data and individual-level breakthrough COVID-19 cases (≥14 days from 2nd dose) using national surveillance data. We ran time-adjusted Cox-proportional-hazards model with sensitivity analysis accounting for varying entry into vaccinated cohort to assess vaccine effectiveness for each vaccine (measured as 1-adjusted hazard ratios) using the unvaccinated population as reference ( N = 565,390). We separately calculated daily cumulative hazards for COVID-19 breakthrough among vaccinated persons by age and vaccination month. Results From February 22 to September 1, 2021, in Almaty, 747,558 (57%) adults were fully vaccinated (received 2 doses), and 108,324 COVID-19 cases (11,472 breakthrough) were registered. Vaccine effectiveness against infection was 79% [sensitivity estimates (SE): 74%–82%] for QazVac, 77% (SE: 71%–81%) for Sputnik V, 71% (SE: 69%–72%) for Hayat-Vax, and 70% (SE: 65%–72%) for CoronaVac. Among vaccinated persons, the 90-day follow-up cumulative hazard for breakthrough infection was 2.2%. Cumulative hazard was 2.9% among people aged ≥60 years versus 1.9% among persons aged 18–39 years ( p < 0.001), and 1.2% for people vaccinated in February–May versus 3.3% in June–August (p < 0.001). Conclusion Our analysis demonstrates high effectiveness of COVID-19 vaccines against infection in Almaty similar to other observational studies. Higher cumulative hazard of breakthrough among people ≥60 years of age and during variant surges warrants targeted booster vaccination campaigns
Cohort · Cohort study · Confidence interval · Disease · Environmental health · Hazard ratio · Population · Proportional hazards model · Retrospective cohort study · Vaccination · Vaccine efficacy · Immune responses and vaccinations · Medicine · SARS-CoV-2 and COVID-19 Research · Vaccine Coverage and Hesitancy · Internal Medicine · Virology
| Unique citing works | 2 |
|---|---|
| Citations per year | 0.67 |
| Citation span | 2023 - 2025 (3) |
| Citation velocity | recent |
| Highly cited | No |
| Citation types | Neutral: 2 |