Five residents of a skilled nursing facility in Kentucky may have been reinfected with coronavirus in the fall after testing positive for the virus in the summer, a new report from the US Centers for Disease Control and Prevention suggests.
The five residents tested positive for Covid-19 in two separate outbreaks three months apart; the first was in July and the second in October. Each of the five residents, aged 67 to 99, received multiple negative tests between the first and second outbreak, the report said.
The five patients were asymptotic or only mildly symptomatic during the first outbreak but experienced more severe symptoms during their second infection. During the second outbreak, one of the five patients required hospitalization and eventually died, the report says.
“The finding that all five patients with recurrent COVID-19 had either asymptomatic or mildly symptomatic courses during the first infection is noteworthy, suggesting the possibility that asymptomatic or mildly symptomatic initial infections do not produce sufficiently robust immune response to prevent reinfection,” the report said.
After the first outbreak, weekly testing of all noninfected health care personnel and residents occurred for more than 14 days after the last positive case was identified. And the Kentucky Department of Public Health encouraged the facility to monitor hand hygiene, emphasize environmental cleaning and disinfection, practice universal masking, use standard precautions for general resident content, restrict visitation based on county-level incidence rates, among other precautions.
“Reinfection risk to the general population is suspected to be low,” the report said. “But SNF residents might have higher risk for new exposures. Based on the observations of this report, testing and cohorting practices in SNFs should not assume that residents infected greater than 90 days earlier are immune to COVID-19.”
The CDC-led team says the findings support the possibility of reinfection, although there is a possibility some of the earlier tests were false positives. Patients’ samples were not stored, so genomic sequencing could not be performed.
“The findings also suggest the possibility that disease can be more severe during a second infection,” the report said.
The report said such facilities should use strategies to reduce coronavirus transmission among residents, including those who have previously had a positive test, and vaccination is key.
A study published in the journal JAMA Internal Medicine this week found that people who tested positive for Covid-19 antibodies were at a decreased risk of coronavirus infection compared with those who tested negative for antibodies, but it noted that more research is needed to determine a causal relationship and for how long protection from antibodies may last.