ArticleEpidemiology and infection2021
Association between live childhood vaccines and COVID-19 outcomes: a national-level analysis.
Article in Epidemiology and infection, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers, 1 of them a synthesis that pooled it.
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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
15 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Effectiveness of Bacille Calmette-Guerin vaccination policies in reducing infection and mortality of COVID-19: a systematic review.Global health research and policy · 2022Pooled it
- Impact of the COVID-19 pandemic on number of deaths in Ghana: an application of ARIMA with intervention analysis.Frontiers in public health · 2025Article
- Impact of the COVID-19 pandemic on routine vaccine landscape: A global perspective.Human vaccines & immunotherapeutics · 2023Review
- BCG vaccination at birth and COVID-19: a case-control study among U.S. military Veterans.Human vaccines & immunotherapeutics · 2022Article
- COVID-19: Some unresolved issues.Revista espanola de quimioterapia : publicacion oficial de la Sociedad Espanola de Quimioterapia · 2022Review
- BCG Vaccination: A potential tool against COVID-19 and COVID-19-like Black Swan incidents.International immunopharmacology · 2022Review
- COVID-19 susceptibility and vaccination coverage for measles, rubella and mumps in students and healthcare workers in Trieste hospitals (NE Italy).Vaccine: X · 2022Article
- The Natural Effect of BCG Vaccination on COVID-19: The Debate Continues.Frontiers in immunology · 2022Article
- Measles, mumps and rubella vaccine and heterologous immunity: a way out of the COVID-19 crisis?Sudanese journal of paediatrics · 2022Review
- Spurious early ecological association suggesting BCG vaccination effectiveness for COVID-19.PloS one · 2022Article
- Effect of BCG on Respiratory Complications Caused by COVID-19: A Scoping Review.International journal of general medicine · 2022Article
- Article
- COVID-19 Severity and Neonatal BCG Vaccination among Young Population in Taiwan.International journal of environmental research and public health · 2021Article
- Covid-19 deaths in Africa: prospective systematic postmortem surveillance study.BMJ (Clinical research ed.) · 2021Article
- BCG as a Vector for Novel Recombinant Vaccines against Infectious Diseases and Cancers.Vaccines · 2020Article
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5 authors.
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Abstract
We investigated whether countries with higher coverage of childhood live vaccines [BCG or measles-containing-vaccine (MCV)] have reduced risk of coronavirus disease 2019 (COVID-19)-related mortality, while accounting for known systems differences between countries. In this ecological study of 140 countries using publicly available national-level data, higher vaccine coverage, representing estimated proportion of people vaccinated during the last 14 years, was associated with lower COVID-19 deaths. The associations attenuated for both vaccine variables, and MCV coverage became no longer significant once adjusted for published estimates of the Healthcare access and quality index (HAQI), a validated summary score of healthcare quality indicators. The magnitude of association between BCG coverage and COVID-19 death rate varied according to HAQI, and MCV coverage had little effect on the association between BCG and COVID-19 deaths. While there are associations between live vaccine coverage and COVID-19 outcomes, the vaccine coverage variables themselves were strongly correlated with COVID-19 testing rate, HAQI and life expectancy. This suggests that the population-level associations may be further confounded by differences in structural health systems and policies. Cluster randomised studies of booster vaccines would be ideal to evaluate the efficacy of trained immunity in preventing COVID-19 infections and mortality in vaccinated populations and on community transmission.
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