It happens every year: As soon as the winter weather breaks and the temperature starts rising as spring approaches, you come down with a cold.
You’re not alone. While the biggest surge in human rhinovirus infections occurs in the fall, springtime also ushers in a second peak season for common colds. Experts say several factors play a part in these seasonal spikes.
In both spring and fall, seasonal allergies can increase a person’s vulnerability to infections, says Dr. Bradley Chipps, president of the American College of Allergy, Asthma & Immunology. The nasal inflammation caused by seasonal allergies makes it easier for viruses to “set up shop” in your nose, Chipps says. Also, since your immune system is preoccupied dealing with your allergies, it has fewer resources available to defend you from illness-causing intruders, he says.
Even if you don’t have allergies, big seasonal swings in barometric pressure, temperature and wind can irritate your airways and nasal passages — and compromise your immune system’s built-in bulwarks against colds and infections, he adds. That may be especially true this year, as the first day of spring — which falls on Tuesday, March 20 — comes amid a brutal end of winter, where a trio of Nor’easters pummeled the East Coast over the last few weeks.
Research also suggests the common cold thrives in cooler temperatures. One recent study from Yale University found a seven-degree drop in ambient temperature can mess with your body’s ability to stop cold viruses from proliferating.
“Every time we’re exposed to infections, we try to counter this by secreting interferons, which are important for blocking viruses,” says Akiko Iwasaki, a professor of immunobiology at Yale School of Medicine. “We found that if you reduce temperatures from 37 to 33 degrees Celsius”—98.6 degrees to 91.4 degrees in Fahrenheit—“that change can dampen immune response and allow viruses to replicate more.”
This helps explain why cold rates leap in the fall when the temperature plummets. But what about springtime?
It’s possible that people are more likely to venture outdoors in March and April than in the wintertime—when the weather has warmed up a bit, but is still cool enough to encourage the spread of cold viruses, Iwasaki says. While a 50-degree fall day may keep you indoors, the same thermostat reading in spring could spur you to break out your running shorts or bike.
The increase in colds in the springtime may also have to do with spring break, Iwasaki adds. “Kids are coming back from trips and spreading things,” she says.
Put simply, a number of different variables can conspire to make you sick when the seasons change. So what can you do to prevent colds as the weather shifts?
“Keeping your nose area warm can keep your immune defenses elevated,” Iwasaki says. Even on cool spring days, wearing a scarf around your face really can make a difference, she adds. Washing your hands regularly—especially before eating or touching your eyes, nose or mouth—is probably the best way to keep illness-causing microorganisms from getting into your body.
Regular exercise and stress-lowering meditation are also research-backed ways to significantly lower your risk for colds. And while the evidence is inconsistent, a recent review study concluded that vitamin D supplements may help protect you from colds and flu.
Keeping your distance from sneezing spring-breakers is also a good idea.