Your health: Cold weather can actually cause colds, study shows
Cold weather can actually cause colds
Whether cold temperatures have anything to do with catching a cold has long been a question that supposedly separates believers in old wives' tales from the scientifically savvy. But while the cold-cold connection is widely considered a medical myth, a new study finds otherwise, Reuters reports.
Even a slight chill increases the speed at which rhinoviruses, which cause the common cold, multiply in lab mice, said the study published recently by Yale University scientists. Cold temperatures also trigger immune-system changes that let the viruses replicate virtually unchecked.
Scientists have suspected for more than half a century that rhinoviruses thrive in a slight chill. A 1960 study found that they multiply more quickly at 33 degrees Celsius (91.4 Fahrenheit) than at body temperature (37C, or 98.6F.).
The new study, published in Proceedings of the National Academy of Sciences, confirmed that finding, showing cold viruses replicated more efficiently and produced higher levels of infectious particles at the lower temperature.
But it also extended the 1960 results, pinpointing three biological effects of chilly air that can increase the likelihood of developing a cold.
In cells lining the mice's nasal passages, genes that produce the virus-fighting protein interferon were less active at 33C than at 37C, Yale immunologist Akiko Iwasaki and her colleagues reported.
In addition, molecules that detect viruses inside cells and then order the cell to produce interferon were less sensitive at colder temperatures. That lower sensitivity reduced production not only of interferon but also of proteins that chop up virus genes, block the release of virus and kill virus-infected cells.
Exposure to a rhinovirus is still a prerequisite for catching a cold. But once a few viruses have entered cells of the nasal cavity, Iwasaki said, inhaling cold winter air exposes those cells to the chill “that the virus likes to replicate” and causes the immune system to respond less aggressively.
Avoiding the flu? Try these apps
Don't want the flu to get you down? Use your smartphone, computer, or tablet to outsmart the virus, Everyday Health advises.
Today's technology offers fun and helpful tools you can view and download to find out everything you need to know about this year's flu season and help you avoid becoming a victim.
These tools provide strategies for preventing the flu — getting the vaccine is still No. 1 — and ways to determine whether your symptoms are the flu or just a common cold. You can even learn about tracking the flu if it invades your neighborhood.
The Centers for Disease Control and Prevention is the official recorder of flu outbreaks in the United States. That might make the CDC's flu app, FluView, the official flu tracker. With this app, you can easily see how severe flu outbreaks are in your state during any given week of the flu season thanks to color-coded maps.
You also can listen to podcasts or watch videos on topics such as protecting babies from the flu and flu-related hospitalizations. It's available for free on iTunes and Google Play.
Flu Near You is a free online program administered by Healthmap of Boston Children's Hospital in partnership with the American Public Health Association and the Skoll Global Threats Fund. Users register and complete surveys to help everyone learn more about the flu.
The app tells you where and how many flu cases have been reported in the United States based on the user-contributed data.
Enter your ZIP code to find out where to get a vaccination and use the links to public health sites to learn more about tracking the flu.