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“Cold season” means more than a bitter breeze. Chilly weather is a prime time to catch a cold. From minor sniffles to major sickness, occurrences of these respiratory illnesses rise as temperatures fall outside:
- Common cold
- COVID-19
- Influenza (flu)
- Pneumonia
Adults may have as many as four common colds between September and May, according to the American Lung Association. Kids could have up to twice as many colds. The Centers for Disease Control and Prevention (CDC) estimated 26-50 million flu cases from October 2022 to April 2023.
Why do people get sick when it’s cold outside? There are some unexpected reasons for cold-weather sickness and some steps you can take to stay healthy this winter.
Related reading: Colds, Flu, and COVID-19: What’s the Difference.
1. Germs spread easier in small indoor spaces.
We spend more time enjoying indoor activities during cold months, sharing spaces from bowling alleys to movie theaters, school classrooms to shopping centers. The time we spend together in smaller places makes it easier for viruses to spread through the air or on high-touch surfaces like doorknobs.
To avoid germs, try not to crowd those around you as you go about your day. Be careful not to rub your eyes, nose, or mouth to avoid transferring a germ from your hands into your body. Wear a face mask for more protection, especially if you’re not vaccinated against the flu or COVID-19. Be sure to wash your hands throughout the day.
2. Viruses travel better through dry air.
It’s normal to get sick in the fall, winter, or chilly beginning of spring, but it’s not actually the cold weather that’s making you sick. Instead, it may be the lack of humidity that helps germs get to you.
Studies show that viruses, especially flu, travel better when the air is dry. And cold temperatures mean dryer air.
Running a clean humidifier may help dampen air and restrict the transmission of flu. Talk with your doctor first to be sure the extra moisture won’t aggravate allergies or any underlying health issues you may experience.
3. Cold temps can slow the immune system.
Some research suggests your immune system slows down when Jack Frost nips at your nose. In fact, the nose plays an important part in filtering out germs. When the nose is cold, virus-attacking cells inside may not work as well as they normally do, making a person more susceptible to sickness.
Bundle up with a warm coat, scarf, gloves, hat, and face covering when you go outside in cold temperatures. Not only will you help protect your skin from dangerous frostbite, but you might protect your immune system, too.
Related reading: Be Mindful of—and Prevent—These 6 Winter Health Risks.
Focus on prevention.
The best way to stay healthy when it’s cold outside is to put prevention first. Here are some tips to keep in mind to help prevent catching or spreading a virus during cold weather and all year long:
- Make sure your flu and COVID-19 vaccinations are up to date.
- Stay home if you feel sick.
- Wash your hands regularly.
- Wear a mask, no matter your vaccination status.
