Breakthrough COVID Rare in Vaccinated Nursing Home Residents

Study finds residents 85 and older more vulnerable if infected, but risk of severe illness in vaccinated residents is low

By MICHAEL CHMURA | Hebrew SeniorLife Research

3 min read

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This article is part of Harvard Medical School’s continuing coverage of COVID-19.

Compared to pre-vaccination cohorts, and despite viral variants, a study published in March in the Journal of the American Medical Directors Association found that the risk of severe COVID-19 among nursing home residents with complete vaccination is low.

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The study found that residents age 85 and older with certain conditions like heart disease and kidney disease were more vulnerable if infected, but the risk of breakthrough SARS-CoV-2 infection among fully vaccinated residents was low.

Examining data for 23,172 fully vaccinated residents at 984 nursing homes from March through November 2021, the study found that 5 percent, or 1,173, developed a SARS-CoV-2 breakthrough infection (BTI) regardless of the different viral variants circulating during the time frame in the study.

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The researchers found that of those 1,173 vaccinated residents with a breakthrough infection 8.6 percent required hospitalization or died within 30 days. Residents with severe infection were more likely to be 85 years of age or older and to have certain conditions, such as heart disease and kidney disease.

“The goal of the study was to examine how often breakthrough infections and severe illness occur among nursing home residents who have received the COVID-19 vaccination series,” said the study’s senior author, Sarah Berry, HMS associate professor of medicine at Hebrew SeniorLife.

“Despite changes in the COVID-19 virus, the risk of severe infection in vaccinated older adults in nursing homes is low. Given that the pandemic continues and testing policies have relaxed, this data provides prognostic information for nursing home facilities faced with continued outbreaks,” Berry added.

The study’s findings are significant, Berry said, because “rates of BTI and serious illness may vary with other variants, but risk factors for serious illness are likely similar and may help providers predict who will get sick during future outbreaks.”

Authorship, funding, disclosures

Additional authors included first author Ana Montoya, of the University of Michigan School of Medicine; Katherine Wen, of Vanderbilt University; Maricruz Rivera-Hernandez, Vincent Mor, and Elizabeth White, of Brown University School of Public Health; and Jasmine Travers, of New York University.

The study was funded by grants from the National Institute on Aging (3U54 AG063546).

The authors declare no conflicts of interest.

Adapted from a Hebrew SeniorLife news release.