* Why Colds and Flu Viruses Are More Common in Winter: CNN
- 'Scientists finally know why people get more colds and flu in winter,' By Sandee LaMotte, CNN, Dec. 6, 2022. - Ed.
A chill is in the air, and you all know what that means — it’s time for cold & flu season, when it seems everyone you know is suddenly sneezing, sniffling or worse. It’s almost as if those pesky cold & flu germs whirl in with the first blast of winter weather. Yet germs are present year-round — just think back to your last summer cold. So why do people get more colds, flu & now Covid-19 when it’s chilly outside? In what researchers are calling a scientific breakthrough, scientists behind a new study may have found the biological reason we get more respiratory illnesses in winter.
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, at Stanford Univ. School of Medicine in Calif.
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 & bacteria-fighting cells in the nostrils, according to the study published Tuesday in The Journal of Allergy & 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, at Mass. Eye and Ear & assoc. professor at Harvard Medical School, Boston. “it’s important to remember that these are in vitro studies, meaning that although it is using human tissue in the lab to study this immune response, it is not a study being carried out inside someone’s actual nose,” Patel said. “Often the findings of in vitro studies are confirmed in vivo, but not always.”
- A hornet’s nest. To understand why this occurs, Bleier & his team went on a scientific detective hunt. As respiratory virus or bacteria invades the nose, the main point of entry into the body. Immediately, the front of the nose detects the germ, well before the back of the nose is aware of the intruder. Then cells lining the nose immediately begin creating billions of simple copies of themselves called extracellular vesicles, or EV’s. They can’t divide like cells can, but EV's are like little mini versions of cells specifically designed to go & kill these viruses.“EV’s act as decoys, so now when you inhale a virus, the virus sticks to these decoys instead of sticking to the cells.” Those EV's are then expelled by the cells into nasal mucus (yes, snot), where they stop invading germs before they can get to their destinations & multiply..
Once created and dispersed out into nasal secretions, the billions of EV’s then start to swarm the marauding germs...
- Read More, https://www.cnn.com/2022/12/06/health/why-winter-colds-flu-wellness/index.html
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- Also: * 'How to Use Food to Boost Your Immune System,' CNN, Nov. 16, 2021,
https://www.cnn.com/2021/11/16/health/food-boost-immune-system-wellness/index.html
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