why we catch colds when the weather changes

Just when we're out of the woods and before the next flu season, cases of the common cold become more likely, for nearly the same reason flu season occurs in the winter.

Rhinoviruses and cornoavirsues — the two agents that typically cause the common cold — replicate more easily in cool, but not too cold weather, Kittu Jindal Garg, M.D., an internal medicine specialist with the Cleveland Clinic, told weather.com.

"A lot of the viruses that cause the common cold are shown to cause outbreaks more frequently in the early to late spring and early to late fall," she said. 

This is basically the same reason flu season occurs in the winter. The structure of the influenza virus allows it to replicate and spread best when air is cold and dry. So it's still the virus, not the cold air, that's causing you to fall ill.

"There have been a lot of studies done, but really there's still no evidence to show that it's the cold weather itself that's making us sick," Dr. Garg said. "It's sort of coincidental that certain viruses flare up this time of year."

In the spring, seasonal sniffing can also come from another culprit: allergies.

"I see a lot of patients who come in and tell me that they've had cold all spring; they've been sick for three months," Dr. Garg said. "Really they don't have a cold at all, but more so their allergies are flaring up."

Those who know they have allergies need to take particular care in the spring. Not only can pollen spark miserable seasonal symptoms, but also allergies leave individuals more likely to catch a cold virus because their immune system is already under attack. 

Unfortunately, over-the-counter supplements, such as echinacea, vitamins E and C and zinc have not been shown to help prevent the common cold in double-blind clinical trials, the gold standard for scientific research. 

What can help? Washing your hands. The cold virus can live on human skin for at least two hours, Dr. Garg said. 

To dodge seasonal sickness, follow the same advice all spring that keeps you healthy year-round. "Having a healthy lifestyle is known to reduce your risk of getting colds," Dr. Garg said. "If you get a moderate level of exercise, and you have good sleep patterns — you're sleeping well and sleeping enough — and not under too much physical or emotional stress [you're less likely to get sick]."

Sources​ ៖ www.weather.com