Detection of sars‐cov‐2 on surfaces in households of persons with covid‐19

Abstract

SARS‐CoV‐2 transmission from contaminated surfaces, or fomites, has been a concern during the COVID‐19 pandemic. Households have been important sites of transmission throughout the COVID‐19 pandemic, but there is limited information on SARS‐CoV‐2 contamination of surfaces in these settings. We describe environmental detection of SARS‐CoV‐2 in households of persons with COVID‐19 to better characterize the potential risks of fomite transmission. Ten households with ≥1 person with laboratory‐confirmed COVID‐19 and with ≥2 members total were enrolled in Utah, U.S.A. Nasopharyngeal and anterior nasal swabs were collected from members and tested for the presence of SARS‐CoV‐2 by RT‐PCR. Fifteen surfaces were sampled in each household and tested for presence and viability of SARS‐CoV‐2. SARS‐CoV‐2 RNA was detected in 23 (15%) of 150 environmental swab samples, most frequently on nightstands (4/6; 67%), pillows (4/23; 17%), and light switches (3/21; 14%). Viable SARS‐CoV‐2 was cultured from one sample. All households with SARS‐CoV‐2‐positive surfaces had ≥1 person who first tested positive for SARS‐CoV‐2 ≤ 6 days prior to environmental sampling. SARS‐CoV‐2 surface contamination occurred early in the course of infection when respiratory transmission is most likely, notably on surfaces in close, prolonged contact with persons with COVID‐19. While fomite transmission might be possible, risk is low.