How cold helps cold viruses
Larissa Melville completed her traineeship in the editorial team of . After studying biology at Ludwig Maximilians University and the Technical University of Munich, she first got to know digital media online at Focus and then decided to learn medical journalism from scratch.
More about the experts All content is checked by medical journalists.MunichSniffing, dripping, blowing your nose: Colds have high season, especially in winter. But is it really the cold to blame?
When the nose is runny, it is usually caused by rhinoviruses. More than 100 different pathogens of this genus are now known. They get stuck in the lining of the nose and throat. However, they can hardly harm humans in warm temperatures, because the immune system then keeps the viruses in check.
This is different at low temperatures: it has long been known that these pathogens feel more comfortable and can multiply better at cooler temperatures. Scientists at Yale University have now discovered another connection between cold and colds: "The cell's own immune response to the rhinoviruses is weakened at colder temperatures," explains study leader Akiko Iwasaki.
Cold weakens the immune system
For the study, the researcher and her team removed airway cells from mice and infected them with rhinoviruses. The scientists cultivated the cells and their virus load once at 33 degrees, which comes close to a cool nose, and the others at 37 degrees. The latter corresponds roughly to normal human body temperature.
The cells were able to defend themselves very well against the viruses at 37 degrees. At 33 degrees, on the other hand, the power of the airway cells weakened. The low temperatures made the cell's own defense even more troublesome than the increased multiplication of the pathogens.
Hostile lodgers
The scientists assume that the result can also be transferred to humans. In the 20 percent of people in whose noses they constantly settle, the cold air immediately enables the pathogens to successfully attack. Other people get infected in full buses or from sneezing colleagues.
The researchers therefore advise you to dress warmly in the cold and, if possible, to protect your nose as well. With this they confirm the often heard saying: "Dress warmly, otherwise you will catch a cold."
Sources:
Foxman, E. et al .: Temperature-dependent innate defense against the common cold virus limits viral replication at warm temperature in mouse airway cells. Proceedings of the National Academy of Sciences. doi: 10.1073 / pnas.1411030112
Yale University press release: Cold virus replicates better at cooler temperatures, January 5, 2015
Tags: vaccinations teenager eyes
