Scientists say they know why people get more colds, flu in winter

Published: Dec. 6, 2022 at 10:44 AM CST

(CNN) - Cold and flu season is here, but germs that cause colds are in the air year-round.

So why do people seem to get sick more in winter?

A new study in the Journal of Allergy and Clinical Immunology may have the answer, and it may sound disappointingly simple.

Colds are caused by the cold - cold weather that is - and the effect it has on your nose.

According to the study, the chilly air damages the immune response in the nostrils.

In fact, reducing the temperature by as little as 9 degrees inside the nose kills nearly half of its virus and bacteria-fighting cells.

Medical experts are calling the finding a scientific breakthrough.

According to one doctor, “This is the first time that we have a biologic, molecular explanation regarding one factor of our innate immune response that appears to be limited by colder temperatures.”