Khaberni - Recent scientific studies have revealed that cold weather is not a direct cause of catching colds or the flu, contrary to popular belief, but it creates biological and environmental conditions that contribute to the spread of respiratory diseases during the winter season.
The research, published on the science platform The Conversation, clarifies that viruses are the real reason for respiratory illnesses, not merely exposure to cold weather.
These viruses include influenza viruses and rhinoviruses, which cause common colds and are transmitted among people through respiratory droplets or direct contact, regardless of the outside temperature.
Despite this, the rates of respiratory diseases see a notable increase during the winter across various regions, which scientists link to the effects of cold and decreased humidity on the survival and spread of viruses.
The studies indicate that viruses live longer in cold and dry environments and remain capable of causing infection compared to warmer and more humid conditions.
Dry air plays an important role in increasing the transmission of infections, as it leads to the rapid evaporation of small droplets produced by coughing, sneezing, or talking, transforming them into finer particles that stay suspended in the air longer, thereby increasing the chances of being inhaled by others.
Inhaling cold air also affects the body's natural defenses, causing the temperature inside the nose and respiratory tract to drop, leading to vasoconstriction and reduced blood flow.
This weakens the local immune response, which typically acts to prevent viruses from causing infection in their early stages.
Along with biological factors, behavioral changes in winter contribute to the exacerbation of the problem, as people tend to spend more time indoors in poorly ventilated spaces, increasing the chances of virus transmission, especially in crowded places.
The decrease in exposure to sunlight during winter also leads to reduced levels of vitamin D in the body, an essential element in supporting immune system functions.
Additionally, indoor heating systems dry out the air, reducing the effectiveness of mucus that acts to trap and expel viruses from the respiratory system.
Researchers confirm that scientific evidence does not support the notion that going out without a coat or feeling cold directly causes illness; rather, cold weather acts as a risk multiplier by providing a suitable environment for the spread of viruses and weakening the body's defenses.
The experts call for focusing on effective prevention, such as improving indoor ventilation, maintaining appropriate humidity levels, and supporting immune health, instead of solidifying misconceptions about the relationship between cold and illness.
