Factors Associated With SARS-CoV-2 Transmission in Settings of High COVID-19 Vaccination Coverage: A Case-Control Study.
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ABSTRACT:
SUBMITTER: Reid MJA
PROVIDER: S-EPMC8903439 | biostudies-literature | 2022 Jun
REPOSITORIES: biostudies-literature
Publications
Factors Associated With SARS-CoV-2 Transmission in Settings of High COVID-19 Vaccination Coverage: A Case-Control Study.
Reid Michael J A MJA Bulfone Tommaso C TC Blat Cinthia C Chen Yea-Hung YH Rutherford George W GW Philip Susan S Gutierrez-Mock Luis L Nickerson Andrea A Buback Laura L Welty Susie S Reingold Arthur A Enanoria Wayne T A WTA
American journal of epidemiology 20220601 7
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Project description:BackgroundResidents of Long-Term Care Facilities (LTCFs) represent a major share of COVID-19 deaths worldwide. Measuring the vaccine effectiveness among the most vulnerable in these settings is essential to monitor and improve mitigation strategies.MethodsWe evaluate the early effect of the administration of BNT162b2-mRNA vaccine to individuals older than 64 years residing in LTCFs in Catalonia, Spain. We monitor all the SARS-CoV-2 documented infections and deaths among LTCFs residents once more than 70% of them were fully vaccinated (February-March 2021). We develop a modeling framework based on the relationship between community and LTCFs transmission during the pre-vaccination period (July-December 2020). We compute the total reduction in SARS-CoV-2 documented infections and deaths among residents of LTCFs over time, as well as the reduction in the detected transmission for all the LTCFs. We compare the true observations with the counterfactual predictions.ResultsWe estimate that once more than 70% of the LTCFs population are fully vaccinated, 74% (58-81%, 90% CI) of COVID-19 deaths and 75% (36-86%, 90% CI) of all expected documented infections among LTCFs residents are prevented. Further, detectable transmission among LTCFs residents is reduced up to 90% (76-93%, 90% CI) relative to that expected given transmission in the community.ConclusionsOur findings provide evidence that high-coverage vaccination is the most effective intervention to prevent SARS-CoV-2 transmission and death among LTCFs residents. Widespread vaccination could be a feasible avenue to control the COVID-19 pandemic conditional on key factors such as vaccine escape, roll out and coverage.
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Project description:Residents of Long-Term Care Facilities (LTCFs) represent a major share of COVID-19 deaths worldwide. Information on vaccine effectiveness in these settings is essential to improve mitigation strategies, but evidence remains limited. To evaluate the early effect of the administration of BNT162b2 mRNA vaccines in LTCFs, we monitored subsequent SARS-CoV-2 documented infections and deaths in Catalonia, a region of Spain, and compared them to counterfactual model predictions from February 6th to March 28th, 2021, the subsequent time period after which 70% of residents were fully vaccinated. We calculated the reduction in SARS-CoV-2 documented infections and deaths as well as the detected county-level transmission. We estimated that once more than 70% of the LTCFs population were fully vaccinated, 74% (58%-81%, 90% CI) of COVID-19 deaths and 75% (36%-86%) of all documented infections were prevented. Further, detectable transmission was reduced up to 90% (76-93% 90%CI). Our findings provide evidence that high-coverage vaccination is the most effective intervention to prevent SARS-CoV-2 transmission and death. Widespread vaccination could be a feasible avenue to control the COVID-19 pandemic.
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