CDC: 5 Kentucky nursing home residents likely reinfected with COVID-19, 1 dies

Several residents in a Kentucky nursing home tested positive for COVID-19 in two separate outbreaks separated by three months, suggesting the possibility of reinfection, according to a report by the U.S. Centers for Disease Control and Prevention.

According to the CDC report published Friday, at least five residents of a skilled nursing facility experienced more severe symptoms in the second outbreak than in the first.

RELATED: Pfizer's COVID-19 shot is 92% effective at reducing severe illness, 'real world' mass vaccination study finds

The Kentucky Department for Public Health (KDPH) and a local health department conducted an investigation at a skilled nursing facility that experienced a second COVID-19 outbreak in October 2020, three months after the first outbreak in July.

"Officials found that five residents received positive test results during both outbreaks. During the first outbreak, three of the five patients were asymptomatic and two had mild symptoms that resolved before the second outbreak," the report said.

Officials found that disease severity in the five residents during the second outbreak was worse than that during the first outbreak and included one death.

RELATED: COVID-19 antibodies were present for up to 3 months in people infected with coronavirus, NIH study finds

Health officials found that all five patients — ranging in age between 67-99 — with recurrent COVID-19 were either asymptomatic or mildly symptomatic during their first infections, suggesting the possibility that asymptomatic or mildly symptomatic initial infections do not produce a sufficiently robust immune response to prevent reinfection, according to the CDC’s report.

The new report noted that the decline in immune system function with aging is well-documented, but little scientific evidence is available to date regarding whether or how an aging immune system might affect response to initial COVID-19 infection, likelihood of reinfection upon new exposure, and illness severity associated with reinfection.

The report urged that "skilled nursing facilities should use strategies to reduce the risk for SARS-CoV-2 transmission among all residents, including among those who have previously had a COVID-19 diagnosis. Vaccination of residents and health care personnel in this setting is particularly important to protect residents."

RELATED: UK judge rules comatose woman with COVID-19 should be removed from life support weeks after giving birth

The news comes after researchers from the National Institutes of Health said they have found evidence that people who have been previously infected by the novel coronavirus appear to be protected against reinfection up to three months.

"The data from this study suggest that people who have a positive result from a commercial antibody test appear to have substantial immunity to SARS-CoV-2, which means they may be at lower risk for future infection," said Dr. Lynne Penberthy, associate director of NCI’s Surveillance Research Program, which led the study.

But the two outbreaks cited in the newest report by the CDC were three months apart, suggesting that protection against the virus may not be as strong after that three-month threshold.

In fact, evidence is mounting that having been previously had COVID-19 may not protect against getting infected again, especially with some of the new coronavirus variants.

In South Africa, a vaccine study found new infections with a variant in 2% of people who previously had an earlier version of the virus, the Associated Press reported.

Meanwhile, in the United States, a study found that 10% of Marine recruits who had evidence of prior infection and repeatedly tested negative before starting basic training were later infected again.