It’s cold and flu season. Here’s a rundown on cold viruses, how you can have two at once, and what you can do to cut down your risk of catching one.

The common cold is a pervasive virus.

In fact, it’s the main reason for children missing school and adults missing work, according to the Centers for Disease Control and Prevention (CDC).

While there are more than 200 virus strains that can contribute to the common cold, the most common are rhinoviruses.

And although the rhinovirus is commonplace and well understood, there’s currently no magic bullet for curing the common cold.

In fact, it’s so common, it’s technically possible for you to catch two colds at the same time.

Experiencing more than one cold during cold season is pretty common, so does that mean that it’s possible to have two colds at the same time?

In short, yes — but if you’ve been feeling sick for a long time, it’s likely one cold after another, rather than multiple colds at the same time.

“In theory, yes, it is possible to have two infections at the same time,” Dr. Brenna Velker, a family physician and adjunct professor at the University of Western Ontario’s Department of Family Medicine as well as a blogger at the Huffington Post, told Healthline. “It’s unlikely that someone would have symptoms from both at the same time, though. Each infection has an incubation period — meaning the time from exposure to infection, to when you actually develop symptoms. Knowing that, it’s actually pretty common around this time of year to have symptoms from one infection, and one or more sitting around in the body waiting to see if the immune system can fight it off.”

“People will often complain that, ‘I’ve been sick for three months!’ Velker added. “While they probably haven’t felt well the whole time, the likelihood is that they’ve been getting one infection after another, and they seem to blend into each other to make one long illness.”

The common cold is easily spread through the air and direct contact with contaminated objects — whether that object is a person’s hand or a surface.

Once infected, a cold can cause those familiar symptoms — sore throat, congestion, runny nose, and sneezing or coughing, sometimes accompanied by fatigue.

Anecdotally, many people will say they experience more cold symptoms during the cold winter months.

Velker told Healthline that there are a few possible reasons for this.

“We definitely see more cases of cold and flu in the winter months,” she wrote in an email. “There are a few theories about why this happens. I think it’s a combination of all of these factors. First, because it’s cold, people spend more time indoors, and therefore more time around others. Second, the viruses that cause the cold and flu seem to be more stable in cold temperatures, meaning that they can stick around longer, and therefore be spread to more people. Third, September means back to school. Kids are exposed to more infectious agents that they likely aren’t immune to, and they bring these back home to share with the rest of the family. Along that same line, back to school often means less sleep, more stress, and less time to do the things that we know keep us healthy, such as exercise and eating well.”

As Velker points out, cold season is also flu season. Since the two ailments often share similar symptoms, it can be tough to determine whether you have a cold or flu.

“In general, with the flu, you feel really sick — achy muscles, fever, headache, et cetera,” wrote Velker. “With a cold, you might have a runny nose, dry cough, and sinus pressure, but you usually aren’t bedridden with the symptoms.”

There’s no way to completely protect yourself or your kids from coming down with a cold, but mindfulness and cleanliness are the best methods when it comes to limiting the risk.

Because the highly transmissible virus can survive on a surface for hours, that age-old medical advice about washing hands is especially important.

Velker recommends handwashing, and added, “All of the time, more than you think you need to,” as well as coughing or sneezing into your elbow or armpit.

When it comes to avoiding the flu, it’s also recommended that everyone get a flu shot during flu season.

It isn’t always necessary to see your doctor if you have a cold, but it’s important to monitor your symptoms.

“You should visit your doctor if you have a fever (temperature over 38.5° C or 101.3° F), if you have a lot of pain, or if your symptoms last longer than 10 to 14 days,” wrote Velker. “Having said that, always see a doctor if you are concerned. The worst that can happen is that they will tell you it’s a virus, and to rest. Importantly, neither a cold nor flu needs antibiotics. Staying off work is a bit trickier. It depends on what your workplace regulations are, what your job entails, and a whole host of other things. A good rule of thumb, though: if you can’t keep your secretions to yourself, you should probably stay away from other people.”

Velker also offers some advice for staying healthy throughout the year: eat healthy, plant-based food, exercise regularly, get enough sleep, and pay attention to your stress levels while making an effort to minimize them.