SARS-CoV-2 likes it cool.

In this preprint, V’kovski et al. investigated the impact of respiratory tract temperature on SARS-CoV and SARS-CoV-2 replication. Primary human airway epithelial cells (hAECs) were infected and maintained at 33 °C or 37 °C to mimic the human upper and lower respiratory tracts, respectively. SARS-CoV-2 replicated more efficiently at 33 °C than at 37 °C but this was not observed for SARS-CoV. Transcriptional analysis of SARS-CoV-2-infected hAECs suggested that stronger and earlier induction of an innate immune programme at 37 °C could explain the enhanced SARS-CoV-2 replication at 33 °C. The evaluation of how temperature impacts interferon responses in a larger number of donors will be essential to understand its effect on SARS-CoV-2 transmissibility and may open new avenues for therapy.