Is Winter Weather Actually Making You Sick? Experts Explain the Link Between Cold temps and Colds
PARIS – As temperatures drop and winter descends, the familiar sniffles and coughs of the common cold seem to become ubiquitous.But is the cold weather directly responsible for catching a cold, or is it a more complex relationship? Experts say the answer is nuanced: cold weather doesn’t cause colds, but it creates conditions that significantly increase the likelihood of viral transmission and weaken our defenses against infection.
the misconception that cold temperatures directly induce illness stems from the timing of cold and flu season. However, colds are caused by viruses, primarily the influenza-in-the-netherlands-december-2022/” title=”State of affairs on … in the Netherlands December 2022″>rhinovirus, which causes inflammation of the upper respiratory tract. What winter does is facilitate the spread of these viruses.
“Confined environments with little or no ventilation concentrate air pollutants which irritate the upper respiratory tract and even aggravate the risk of infections,” explains Manuel Rosa-Calatrava, deputy director of the Laboratory of virology and Human Pathology, in an interview with HuffPost. The shift in behavior during colder months – opting for the metro over biking, meeting indoors instead of in parks, and reducing ventilation – provides ample possibility for viruses to spread. These viruses travel via “micro droplets produced by your sneezes and coughs,” as well as contaminated tissues.
Beyond behavioral changes, the cold itself impacts our respiratory system’s ability to fight off infection.Winter air dries and cools the mucous membranes in our noses, hindering the function of cilia – tiny structures responsible for trapping dust and pathogens. Irritated mucous membranes offer viruses easier access.
Moreover, inhaling cold air can weaken our immune defenses. The body responds to cold by initiating vasoconstriction – a reduction in the size of blood vessels – to maintain core temperature. While helpful for warmth, this process “has the effect of reducing the activity of white blood cells,” according to Rosa-Calatrava, effectively giving rhinoviruses a clearer path.
the temperature itself impacts viral survival and transmission. Studies suggest that the influenza virus, responsible for the flu, survives longer at 5°C (41°F) than at 20°C (68°F), especially in low humidity – conditions common in winter in temperate zones. “Studies carried out on guinea pigs suggest that the seasonal influenza virus survives longer at a temperature of 5°C than 20°C and particularly when absolute humidity is low,” Rosa-Calatrava adds.
So, while the cold isn’t the culprit, it’s a notable contributing factor. The moast effective defense? Simple preventative measures: wash your hands frequently, both if you’re feeling unwell and to prevent infection, and prioritize ventilation when possible.
