A review of data from Chicago nursing homes found that fully vaccinated residents and staff accounted for just 4% of COVID-19 infections recorded since the start of the federal vaccine rollout, with just a single resident death — and no secondary transmission within facilities.
The findings, published by the Centers for Disease Control & Prevention (CDC), emphasize the importance of vaccinating residents and staff, while also remaining vigilant about compliance with proven COVID reduction protocols.
“SNFs should prioritize vaccination and follow recommended COVID-19 infection prevention and control practices, including following work restrictions, isolation, quarantine, testing of residents and staff members, and use of personal protective equipment,” the study authors concluded in the analysis, published as a CDC Morbidity and Mortality Weekly Report (MMWR).
Researchers tracked COVID-19 infection data from the 78 skilled nursing facilities in Chicago, which became eligible for federal vaccine clinics last December 28. Through February, nearly 8,000 residents and almost 7,000 staffers received both doses; during that same period, health department officials identified 627 confirmed COVID-19 cases at 75 of the city’s facilities — 353 in residents and 274 in staff — with only three SNFs remaining COVID-free during that span.
Taken together, 71% of those total infections were among unvaccinated people, with just 22 — or 4% of the total — in those who were fully vaccinated, according to the researchers. Officials found 145 positive cases in people who were partially vaccinated, and 13 among who had received both shots but had not yet achieved full immunity.
Of the 22 so-called “breakthrough infection” cases, only about a third resulted in symptoms of any kind, with 14 remaining asymptomatic. Five people experienced mild symptoms, and four were hospitalized — two apiece for COVID and non-COVID reasons, the researchers found. One resident died.
“The death certificate listed complications of COVID-19 infection as primary cause of death; underlying conditions were hypertension, diabetes mellitus, and chronic kidney disease,” according to the report.
Those who had acquired breakthrough infections also did not spread it to others in their facilities.
“No facility-associated secondary transmission was determined to have occurred because the new cases that occurred after the initial breakthrough infection were not close contacts of the persons with breakthrough infections,” the researchers observed.
The upshot: COVID-19 vaccination remains imperative for those who live and work in nursing facilities.
“The results in this report highlight the importance of COVID-19 vaccination in high-risk congregate settings such as SNFs; most fully vaccinated persons were not infected, did not have COVID-19–like symptoms, and did not have severe illness,” the team concluded.
The Chicago study was released the same day as a separate MMWR about a COVID-19 outbreak at a Kentucky nursing home triggered by an unvaccinated worker. In that case, researchers determined that the vaccine helped blunt the outbreak’s impact, reducing the risk of symptoms by 87% in both workers and residents. Among 44 positive cases, three residents died — one of whom had been vaccinated.
“To protect SNF residents, it is imperative that [workers], as well as SNF residents, be vaccinated,” the authors of the Kentucky study wrote. “A continued emphasis on strategies for prevention of disease transmission, even among vaccinated populations, is also critical. Timely implementation of infection control strategies after outbreak identification likely contributed to the rapid decline in new cases during the second week of the outbreak.”
