SARS-CoV-2 reinfects 5 in nursing home, causing worse disease, 1 death
Five residents of a skilled nursing facility in Kentucky were likely reinfected with COVID-19, and the disease was worse the second time, with one patient dying, according to today’s Morbidity and Mortality Weekly Report (MMWR).
Between the two outbreaks, which were reported in July and October 2020, each resident had at least four negative reverse-transcription polymerase chain reaction (RT-PCR) tests.
From Jul 16 to Aug 11, 2020, 20 of 115 residents (17.4%) and 5 of 143 (3.5%) healthcare personnel (HCP) tested positive for COVID-19 for an attack rate of 9.7% and 5 resident deaths. The outbreak was considered over after more than 2 weeks elapsed after the last identified case, and from Sep 1 to Oct 29, 2020, 928 COVID tests were performed—biweekly for HCP and upon symptom onset for residents—and all were negative.
During the second outbreak, which occurred Oct 30 to Dec 7, 2020, 85 of 114 (74.6%) of residents and 43 of 146 HCP (29.5%) had positive COVID-19 tests, for an attack rate of 49.2%. Fifteen infected residents (17.6%) died.
Twelve residents who were positive in the first outbreak were there during the second, and 5 of them tested positive again. Of these 5, 3 were asymptomatic and 2 had only mild symptoms during the first outbreak. But during the second, all 5 had symptoms, and the 2 with mild symptoms in the first outbreak had more severe symptoms in the second.
Sufficient RT-PCR test results to suggest at least moderate upper respiratory tract viral loads, and those who had previous symptoms had worse outcomes. One resident who was asymptomatic in the first outbreak died after the second infection and a 7-day hospital stay.
The reinfected residents were ages 67 to 99. All had at least three underlying health conditions but were not immune-suppressed. Because test samples weren’t kept, the investigators don’t know how related the outbreaks’ phylogenetic strains were.
“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,” the researchers write. “Vaccination of residents and health care personnel in this setting is particularly important to protect residents.”
Feb 26 MMWR study
Sharing a home brings a 10% COVID-19 risk after exposure, study says
People who share a household with a member who has COVID-19 have a 10.1% risk of infection, according to a research letter published today in JAMA Network Open.
The retrospective cohort study used electronic records from the Mass General Brigham health system to track 7,262 COVID-19 index cases and their 17,917 household contacts from Mar 4 to May 17, 2021. During the study period, 1,809 household members (10.1%) were diagnosed as having COVID-19 a median of 3 days after the index diagnosis.
Independent risk factors included adult age and comorbidities. Household contacts from 50 to 64 had an adjusted odds ratio (aOR) of 3.66 (95% confidence interval [CI], 2.92 to 3.66; P < 0.001), the highest increased risk across those 19 and above. High blood pressure and liver disease was associated with the highest risk among comorbidities, with aORs of 1.93 (95% CI, 1.58 to 2.44; P < 0.001) and 2.01 (95% CI, 1.32 to 3.07; P = 0.001), respectively.
One of the study’s limits was the electronic medical records’ ability to identify household members accurately. To mitigate this, the researchers didn’t include household members who did not visit the health system in the past 5 years or households with more than 25 residents.
“Although we acknowledge that contact investigations are the standard approach for estimating household transmission risk, we believe that the consistency of our results with these approaches suggests that our approach may provide a more efficient method for risk estimation and household contact identification,” they write.
The researchers also note that the short median interval between the index case and subsequent cases may indicate some common exposures instead of transmissions. Cases also may have been undercounted if they did not seek medical attention.
Even so, the authors write, “Our study showed an overall household infection risk of 10.1%, consistent with reported transmission risk based on more traditional contact tracing, including a recent meta-analysis that reported an overall transmission risk of 17.1%, although there was wide variation across studies.”
Feb 26 JAMA Netw Open research letter