Recent scientific evidence suggests that the relationship between cold weather and respiratory illnesses is more complex than previously thought.
Scientific research has revealed that low temperatures in themselves do not cause colds and influenza, but they create ideal conditions for the spread of respiratory viruses through several complex mechanisms.
Cold weather affects several factors, including biological, environmental, and social factors, increasing people's susceptibility to respiratory diseases.
One of the reasons people are getting more of these diseases, according to research, is that viruses that cause respiratory illnesses such as influenza and rhinoviruses remain infectious for longer periods in cold and dry weather.
The evaporation of respiratory droplets in dry air also leads to the formation of microscopic particles that remain suspended in the air for a longer period, increasing the chances of infection transmission.
Physiological effects on the body
Inhaling cold air causes blood vessels in the respiratory system to constrict, reducing blood flow and weakening the local immune response. Additionally, the dryness of winter air thins the protective mucus layer in the nose and throat, which is the first line of defense against respiratory pathogens.
Environmental and behavioral factors
Cold weather conditions encourage people to spend more time indoors in crowded places, facilitating the transmission of viruses through respiratory droplets. Winter is also associated with reduced sun exposure, leading to lower levels of vitamin D, which is essential for optimal immune function.
Experts confirm that those with chronic respiratory illnesses such as asthma experience a worsening of symptoms during the colder months, due to increased sensitivity of the airways to cold, dry air.
The researchers concluded that the spread of respiratory diseases in winter is not the result of a single factor, but rather the result of a complex interaction between viral, physiological, environmental and behavioral factors that together increase the population's susceptibility to infection.
