Touching surfaces

| 5 November 2020 | The estimated risk of infection from touching a contaminated surface was less than 5 in 10,000 in a study by Amy Pickering, Abigail Harvey and colleagues. From April to June 2020, they repeatedly sampled 33 surfaces in public places like liquor and grocery stores, banks, gas stations, laundromats, restaurants and on metro doors and crosswalk buttons. Twenty-nine of 348 (8.3 %) surface samples were positive for SARS-CoV-2. The authors suggest that fomites might play only a minimal role in SARS-CoV-2 community transmission.

A second, not less important point: The weekly percentage of positive samples in one postal district peaked about 7 days before a spike in new SARS-CoV-2 cases. Surveillance on high-touch surfaces might therefore provide precious early warning clues.

Harvey AP, Fuhrmeister ER, Cantrell M, et al. Longitudinal monitoring of SARS-CoV-2 RNA on high-touch surfaces in a community setting. medRxiv 2020, posted 1 November. Full-text: https://doi.org/10.1101/2020.10.27.20220905