Pfizer-BioNTech Vaccine Protects Skilled Nursing Facility Residents as Effectively as General Population

Partial vaccination against the novel coronavirus (COVID-19) with the Pfizer-BioNTech vaccine was 63 percent effective among residents of skilled nursing facilities, according to the U.S. Centers for Disease Control and Prevention’s (CDC) Morbidity and Mortality Weekly Report (MMWR).

CDC investigators conducted a retrospective cohort analysis in 2 Connecticut skilled nursing facilities in order to assess vaccine effectiveness among residents, who they noted are often more medically frail, older, and have more underlying medication conditions compared to the general population. This population was not included in COVID-19 vaccine trials, so little data its known about how well the vaccine can protect the skilled nursing facility residents.

These types of facilities began receiving the Pfizer-BioNTech vaccine in mid-December 2020 but the Connecticut Department of Public Health (CT DPH) identified 2 facilities experiencing COVID-19 outbreaks among residents and staff in late January 2021, the study authors explained.

These 2 facilities subsequently surveilled 463 residents through weekly testing after the outbreak. The study authors said that all residents who had not received a positive test result in the previous 90 days, regardless of their symptoms, received a once-weekly or twice-weekly (depending on the facility) PCR test. Staff was also tested. If a resident or staff member was experiencing COVID-19 symptoms or had known exposures, that individual received a supplementary antigen test, the study authors noted.

The CT DPH and the CDC reviewed medical records through mid-February including vaccination status and infection with COVID-19. The investigators defined partial vaccination as the period from > 14 days after the first dose through 7 days after the second dose and found that partial vaccination had an estimated effectiveness of 63 percent for this population, they wrote.This is a similar rate of effectiveness for this particular vaccine across a wide swath of age groups in non-facility settings, the study authors added.

The study authors wrote that their findings suggest the complete 2-dose series should be recommended for residents and staff at skilled nursing facilities.

During the study period, there were 97 COVID-19 cases among residents at 2 facilities, who experienced nonspecific symptoms such as malaise, lethargy, and decreased appetite, the study authors found. By the date of discharge or the last day of the study period, 304 residents had received 2 vaccine doses (65 percent of residents), 72 had received only 1 dose (15 percent), and 87 residents had received no doses (18 percent).

Due to the course of outbreaks at the facilities, the study authors noted, most cases occurred in the beginning of the study period. They added that once residents became fully vaccinated, including 7 days after the second dose, there were insufficient new cases and there could not be a comparison to an unvaccinated group to determine vaccine effectiveness accurately.

“Even during a large disease outbreak in a long-term care setting, the Pfizer-BioNTech vaccine provided protection against SARS-CoV-2 infection, including in older adults aged ≥ 65 years with a high prevalence of underlying medical conditions,” the authors concluded. “The findings in this report are comparable to other first-dose vaccine efficacy and effectiveness estimates for the Pfizer-BioNTech vaccine for the broader adult population in noncongregate settings.”

Finally, the study authors suggested that long-term care facilities should be actively engaged in ensuring that they have plans in place for continued vaccine distribution and administration for residents and staff members.