Common Cold Coronaviruses Detection at an Academic Hospital Before and During COVID-19 Pandemic

Abstract

Abstract Background Community mitigation measures implemented during the COVID-19 pandemic altered the seasonality of some respiratory viruses, including the four common cold coronaviruses (CCCs). Since these measures have been relaxed, CCCs have resurged, but limited longitudinal data on CCCs circulation are available to interpret changes in prevalence during the pandemic. Therefore, we defined circulation of the four CCCs before and during the COVID-19 pandemic in Nashville, TN, for insights into the impact of pandemic human coronavirus emergence and associated containment measures on CCCs infections in the general population. Methods We conducted a retrospective cohort study of clinician-ordered respiratory virus panels from 01/01/2018 to 12/31/2022 at Vanderbilt University Medical Center (Nashville, TN). The panels test for common respiratory pathogens, including CCCs (namely HCoV-229E, -NL63, -OC43, and -HKU1). Overall and age-specific detection frequencies for the four CCCs were analyzed. Multiple medical encounters for the same individual were included if they were >14 days apart. The beginning of the pandemic was marked by 04/01/2020, the first day Tennessee’s stay-at-home order was in effect. Results A total of 57,930 samples were tested, and 2,003 (3.5%) were CCC-positive. The most frequently detected CCC was OC43 (n=785; 39.2%), followed by HKU1 (n=510; 25.5%), NL63 (n=510; 25.5%), and 229E (n=237; 11.8%). Before the pandemic, CCCs peaked during winter months. This seasonality was disrupted during the pandemic; circulation virtually ceased in April 2020 and resumed in January 2021, peaking during the spring months of 2021 and 2022. Throughout the study duration, OC43 predominated each season except for the 2019–2020 winter months, when HKU1 was predominant (Figure 1). The seasonality of all four CCCs was generally consistent across age groups; however, 229E was uncommon in children 0–4 years. Figure 1. Detection frequency of the four common cold coronaviruses detected between January 2018 and December 2022 in Nashville, TN, by age group. The dashed line represents the first day Tennessee’s stay-at-home order was in effect. Conclusion The four CCCs circulated off-season in Nashville during the pandemic, exhibiting spring seasonal peaks in 2021 and 2022. Long-term monitoring of CCC circulation is required to determine whether the shift in seasonality becomes a permanent feature of CCC ecology. In addition, further studies are warranted to explain the varying predominance of HCoV-OC43 and HCoV-HKU1.