3 Strange Facts About the Common Cold You Should Know

When the leaves begin to fall, the rainy days return and pumpkin spice is back on the menu, something else is around the corner too — that never-ending runny nose. While you can catch a cold any time of the year, your chances of getting sniffly are much higher during back-to-school season as the temperatures drop and your little ones bring home the classroom’s virus-of-the-week — again.

Catching a cold might feel like a run-of-the-mill experience, but you might not know as much about it as you thought. Dr. Melissa Mossar, a primary care provider at UW Medicine Primary & Urgent Care at Ballard, shares some surprising facts about the common cold and how it spreads.

Hundreds of viruses can cause a cold — it’s likely not the same one each time

Rhinoviruses are likely the culprits that cause the common cold. However, Mossar says hundreds of viruses can cause a cold, including coronaviruses (not to be confused with COVID-19, which is caused by SARS-CoV-2), parainfluenza viruses, adenoviruses, enteroviruses and human metapneumovirus. Colds from these other viruses can have the same symptoms as colds caused by a rhinovirus — runny nose, sneezing, sore throat, etc. — but they’re not encountered as frequently.

Because of the large number of these viruses in our environment, most adults can expect to catch an average of two to three colds per year, and kids can expect six to eight colds per year.  

Another reason that we get so many colds is because one virus can continue to mutate after we build immunity to it. Later variants can then keep making us sick. The rhinovirus is especially interesting because it can spread dozens of variants around simultaneously.

“With viruses like SARS-CoV-2 or influenza, one variant will dominate for a while and then another takes over, and it, in turn, is replaced by another,” said Dr. Alex Greninger, professor of laboratory medicine and pathology at the University of Washington. “Rhinovirus, on the other hand, appears to flood the zone with many discrete variants circulating in the community at the same time. It’s a way to overcome your defenses with sheer numbers.”

Another unbelievable fact? It’s possible to catch multiple viruses, like the flu or COVID-19 and the common cold, at the same time. 

Your stuffy nose could potentially be blamed on ... erectile tissue

You read that correctly. While we usually think about the erectile tissue in our sexual organs, tissue inside your nose can also become engorged with blood (but with different physiology).  

This means that when allergies or an infection like the infamous rhinovirus irritate your nasal passages, the swelling in your nose’s erectile tissue can block your airflow, resulting in the much-dreaded stuffy nose. This is also why blowing your nose doesn’t always help — sometimes it’s mucus blocking those passages; sometimes, it’s the swelling.

If you’re looking for relief from a stuffy, congested nose, you’re more likely to feel better after using decongestants like Sudafed or Afrin because they reduce the swelling in your nasal passages.  

Cold medications don’t actually kill your cold

Medications exist to help treat some viruses, like nirmatrelvir/ritonavir (a.k.a. Paxlovid) for COVID-19 or oseltamivir (a.k.a. Tamiflu) for the flu. Antibiotics can be used to fight bacterial infections like strep throat, but Mossar says there are no medications that will cure the common cold.

Over-the-counter cold medicine can alleviate your symptoms and make them easier to tolerate, but in the end, that’s all it’s doing — it’s not targeting the viruses themselves.

When you’re trying to recover from a cold, Mossar says, your body will likely respond best to rest, self-care and drinking plenty of water — no need to splurge on medication that claims to get rid of your cold in 24 hours (that’s just your immune system doing good work).

Also, beware: viruses that cause the common cold can live on surfaces for up to two days. The best way to prevent the spread of a cold (or catching one yourself) is to wash your hands regularly.

Tips to stay protected

In addition to frequent hand washing and staying hydrated, here are some other tips to keep you healthy and cold-free:

Stay active: There’s some evidence that mild exercise can prevent colds and help them go away a little quicker.  

Avoid touching your face: This is hard, especially if you’re a chronic eye-rubber, nail-biter or cheek-on-hand rest-er. However, there’s always a chance you’ve encountered a virus, and avoiding contact with your eyes, nose and mouth can prevent you from getting sick.

Don’t share towels or household items: If someone in your house has or recently recovered from a cold, don’t sip from their cup or share a hand towel with them. Remember — the virus can live on surfaces for a long time.

Stay up to date on your annual vaccines: Getting your flu and COVID-19 boosters won’t prevent you from catching a cold-causing virus, but they can help prevent you from being stuck in bed recovering from both the flu and a cold.

Get plenty of sleep: Your body needs time to repair itself and fight against viruses — getting a good night’s rest is a great way to help it do so. 

Some material in this story originally appeared in the UW Medicine Newsroom.