Mechanistic view on the influence of fluctuations in outdoor temperature on the worsening of the course of the disease and hospitalizations associated with the SARS-CoV-2 Omicron wave in 2022 in the Tomsk region, Russia

It is well known that low air temperatures negatively affect the human respiratory system and can suppress protective mechanisms in airways epithelial cells. In this study, we put forward the hypothesis that the compromised airway epithelium of infected persons can be extremely sensitive to external influences and therefore can be used as an "indicator" and serve to investigate the impact of low air temperatures (as and other external factors) on the respiratory system. Here we supposed that a short-term impact of drop in outdoor temperature on the compromised airway epithelium should lead to increased symptoms and severity of the disease. We have analyzed a short-term impact of the air temperature drop on the worsening of disease in patients with COVID-19 (indicated by bursts of daily hospitalizations), which fell on the main epidemic wave in 2022 associated with SARS-CoV-2 Omicron variant. It was found that even a small and/or short-term impact of drop in outdoor daily temperatures can lead to increased symptoms and severity of the disease (COVID-19). We have identified 14 characteristic points (days) where the temperature drop was more than 3 degrees during the main pandemic wave in 2022. It was shown that each characteristic points clearly associated with characteristic bursts in the number of daily hospitalizations with a time lag of 1-2 days. Thus, it was found that the results of the study can be used in predicting a sudden increase in the number of hospitalizations, which can be used to timely warn clinics and medical hospitals for an increase in the number of seriously ill patients. The findings can be used to improve systems to prevent additional risks connected with impact of drop in air temperature on worsening disease in patients and infected people who do not have or have mild or subtle symptoms of the disease - especially during an epidemic or pandemic wave.