Scientists finally discover why people get more colds and flu in cold temperatures
More common during the winter months, scientists have uncovered the biological reason why colds are more prevalent in colder temperatures.
A study suggests the newly discovered immune response inside the nose is suppressed by colder temperatures, and the illnesses are not more common simply because people are stuck indoors.
Scientists say this finding offers the first biological evidence for why respiratory illnesses like colds, flu and Covid-19 are more likely to spike when the temperature drops.
It turns out the cold air itself damages the immune response occurring in the nose.
“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,” said rhinologist Dr. Zara Patel, a professor of otolaryngology and head and neck surgery at Stanford University School of Medicine in California. She was not involved in the new study.
In fact, reducing the temperature inside the nose by as little as 9 degrees Fahrenheit (5 degrees Celsius) kills nearly 50% of the billions of virus and bacteria-fighting cells in the nostrils, according to the study published Tuesday in The Journal of Allergy and Clinical Immunology.
“Cold air is associated with increased viral infection because you’ve essentially lost half of your immunity just by that small drop in temperature,” said rhinologist Dr. Benjamin Bleier, director of otolaryngology at Massachusetts Eye and Ear and an associate professor at Harvard Medical School in Boston.