Higher transmissibility of certain viruses could be one reason. If more people are catching it, it's not hard to imagine that more people are getting sick from

Higher transmissibility of certain viruses could be one reason. If more people are catching it, it's not hard to imagine that more people are getting sick from it, and infecting others. From one study: > Our study shows an important dependency of SARS-CoV-2 transmission to weather/climate, with each 1°C reduction in mean regional temperature below 10°C leading to a 0.16-unit increase in R0 , or each 1 g/m3 reduction in AH leading to a 0.15-unit increase in R0. Northern hemisphere countries experienced a new wave of SARS-CoV-2 infections during autumnal transition from summer to winter (colder temperatures and lower absolute humidity levels), while still actively maintaining control strategies. When planning to adjust the level of restrictions on social activities, public health strategies need to account for the increased transmissibility of SARS-CoV-2 when/where cold and dry winter conditions are prevalent. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8211690/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8211690/