Infectious Period of Severe Acute Respiratory Syndrome Coronavirus 2 in 17 Nursing Home Residents—Arkansas, June–August 2020

Abstract

Background To estimate the infectious period of SARS-CoV-2 in older adults with underlying conditions, we assessed duration of COVID-19 symptoms, reverse-transcription polymerase chain reaction (RT-PCR) positivity, and culture positivity among nursing home residents. Methods We enrolled residents within 15 days of their first positive SARS-CoV-2 test (diagnosis) at an Arkansas facility from July 7–15, 2020 and followed them for 42 days. Every 3 days for 21 days and then weekly, we assessed COVID-19 symptoms, collected specimens (oropharyngeal, anterior nares, and saliva), and reviewed medical charts. Blood for serology was collected on days 0, 6, 12, 21, and 42. Infectivity was defined by positive culture. Duration of culture positivity was compared to duration of COVID-19 symptoms and RT-PCR positivity. Data were summarized using measures of central tendency, frequencies and proportions. Results We enrolled 17/39 (44%) eligible residents. Median participant age was 82 years (range: 58–97 years). All had ≥3 underlying conditions. Median duration of RT-PCR positivity was 22 days (interquartile range [IQR]: 8–31 days) from diagnosis; median duration of symptoms was 42 days (IQR: 28–49 days). Of nine (53%) participants with any culture-positive specimens, 1 (11%) severely immunocompromised participant remained culture-positive 19 days from diagnosis; 8/9 (89%) were culture-positive ≤8 days from diagnosis. Seroconversion occurred in 12/12 (100%) surviving participants with ≥1 blood specimen; all participants were culture-negative before seroconversion. Conclusion Duration of infectivity was considerably shorter than duration of symptoms and RT-PCR positivity. Severe immunocompromise may prolong SARS-CoV-2 infectivity. Seroconversion indicated non-infectivity in this cohort.

Descriptive evaluation of antibody responses to severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infection in plasma and gingival crevicular fluid in a nursing home cohort—Arkansas, June–August 2020

“…Following antibody detection in plasma or GCF, replication-competent SARS-CoV-2 was not recovered from any participant in our cohort. These findings are consistent with previous reports 14,22,30 indicating binding antibodies could have served as an early humoral marker of non-infectivity among these participants. Further, the slightly earlier detection of plasma pan-Ig and IgG antibodies in this evaluation suggests that these isotypes could serve as even timelier markers.…”

“…The three excluded residents had blood collected only at enrollment and were SARS-CoV-2 antibody negative; two did not provide any GCF specimens, and 1 provided a single GCF specimen but with insufficient volume for testing. Among the 14 included participants, all (100%) provided >1 GCF specimen and 12 (86%) provided >1 blood specimen; Surie et al 14 .…”

“…We enrolled a prospective cohort of SARS-CoV-2 infected nursing home residents identified during serial point prevalence surveys from a single nursing home experiencing a COVID-19 outbreak during June-August 2020, as described previously 13,14 . Participation was voluntary and residents were eligible for enrollment if cognitively capable of providing verbal and written informed consent.…”

Persistence of infectivity in elderly individuals diagnosed with severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infection 10 days after onset of symptoms: A cross-sectional study

“…2 By contrast, recovery of replication-competent SARS-CoV-2 was 8 days or less after diagnosis in 8 of 9 nursing home residents in Arkansas, although infectivity persisted for 19 days in 1 immunocompromised individual. 10 Our study has several limitations. The small sample size limits its generalizability.…”

Repeated antigen testing among severe acute respiratory coronavirus virus 2 (SARS-CoV-2)–positive nursing home residents

“…For comparison, Surie et al found that PCR positivity can last as long as 48 days in a nursing home cohort. 12 Antigen results were consistently positive for many participants. Some false-and intermittently-positive specimens occurred among specimens preceded or followed by antigennegative specimens, RT-PCR-negative specimens, or specimens with high Ct values, possibly reflecting later stages of infection when viral loads are waning.…”