Potential impact of seasonal forcing on a SARS-CoV-2 pandemic

Richard A Neher; Robert Dyrdak; Valentin Druelle; Emma B Hodcroft; Jan Albert

(2.2 with 90% high density interval 1.4-3.8 (Riou and Althaus, 2020) or 2.7 with a 95% CrI of 2.47-2.86 (Wu et al., 2020) ). Higher estimates have also been reported (Sanche et al., 2020; Yang et al., 2020) . Importantly, R 0 is not a biological constant for a pathogen, but is affected by factors such as environmental conditions and the behaviour of infected individuals. One such environmental factor is climate which modulates transmissibility throughout the year. As a result, many respiratory viruses show clear seasonal variation in prevalence; the most well-known example being seasonal influenza which peaks every winter in the temperate zone of the Northern Hemisphere (Petrova and Russell, 2018) . A similar pattern is seen for the four seasonal human coronaviruses: HKU1, NL63, OC43 and 229E (hereafter collectively referred to as "seasonal CoVs") (Al-Khannaq et al., 2016; Friedman et al., 2018; Galanti et al., 2019; Góes et al., 2019; Huang et al., 2017; Killerby et al., 2018) . These viruses cause respiratory infections which usually are mild and primarily affect young children.