« Can you really catch a cold?
While many people thought that catching a cold was just a popular belief, a new American study proves that there is indeed a link between low temperatures and the prevalence of respiratory tract infections.
Explanations.
Is it possible to catch a cold?
Until now, it was thought that respiratory infections were more common in winter due to more frequent indoor gatherings and the resistance of viruses to cold temperatures.
That’s true, but in addition to these factors, there is indeed a link between » seasonal variation » and « prevalence of upper respiratory tract infections « .
That’s what American researchers proved in a study led by Mansoor Amiji, professor at Northeastern University.
In a previous study in 2018, the researcher had already discovered that nose cells release extracellular vesicles to attack bacteria on entry.
In a new study, the researcher and his team then asked whether the response of extracellular vesicles could be affected by temperatures.
Exposure to cold alters nasal antiviral immunity
According to results published on November 5, 2022 in the Journal of Allergy and Clinical Immunology, exposure to cold does indeed impair nasal antiviral immunity.
To reach this conclusion, the researchers used the nasal mucosa of volunteers and substances representing viral infections.
Nasal mucous membranes were divided into two groups: the first with cells grown in the laboratory at 37°C (the « normal » body temperature when the air is 23°C), and the second with cells grown at 32°C (to match the temperature of the nose when the outside thermometer falls to 4°C).
The result ? Under normal body temperature conditions, the extracellular vesicles were able to fight off the viruses.
In contrast, at lower temperatures,extracellular vesicles were produced in smaller numbers and proved less effective against the viruses tested (two rhinoviruses and a coronavirus other than SARS-CoV-2).