section_path: Epidemiology/Weather
section_name: Weather
paragraph_text: Weather
  
  A common misconception is that one can "catch a cold" merely through prolonged exposure to cold weather. Although it is now known that colds are viral infections, the prevalence of many such viruses are indeed seasonal, occurring more frequently during cold weather. The reason for the seasonality has not been conclusively determined. Possible explanations may include cold temperature-induced changes in the respiratory system, decreased immune response, and low humidity causing an increase in viral transmission rates, perhaps due to dry air allowing small viral droplets to disperse farther and stay in the air longer.
  
  The apparent seasonality may also be due to social factors, such as people spending more time indoors near infected people, and especially children at school. Although normal exposure to cold does not increase one's risk of infection, severe exposure leading to significant reduction of body temperature (hypothermia) may put one at a greater risk for the common cold: although controversial, the majority of evidence suggests that it may increase susceptibility to infection.