Can You Get COVID-19 From Secondhand Smoke?

If the person standing next to you is smoking a cigarette, could breathing in the secondhand smoke give you COVID-19? In a word—possibly.

There are several different ways that secondhand smoke can increase your risk of becoming infected with COVID-19, and these include smokers' mask removal, respiratory particles, and the risk of lung disease.

"Since the novel coronavirus is spread via direct person-to-person contact, activities that include being in close contact (less than six feet) without a mask on should be avoided, which includes secondhand smoke," said Julie Yoo, MD, MPH, a pulmonologist with St. Jude Heritage Medical Group in Fullerton, California. "The act of smoking requires the person to take off the mask, so this is considered a high-risk environment for anyone in the vicinity."

Droplets and Aerosols

The disease spreads when tiny respiratory droplets containing SARS-CoV-2, the virus that causes COVID-19, are exhaled. If an infected person coughs, sneezes, talks, sings, or simply breathes in your vicinity, you can contract the virus.

The same droplets people spray when they're coughing, sneezing, or talking are exhaled when they're smoking or vaping.

"It's plausible to presume that a plume of smoke, which is comprised of respiratory droplets, can result in COVID-19 transmission," said Osita Onugha, MD, thoracic surgeon and assistant professor of thoracic surgery at the John Wayne Cancer Institute in Santa Monica, California.

Studies suggest that some of the smaller COVD-19 droplets can become suspended in air, lingering for a duration of time. For example, one study stated that "aerosols are an important transport route for SARS-CoV-2, as aerosol particles can contain the infectious SARS-CoV-2, and remain suspended in the air for hours, which may be up to several meters transported from the source."

Inhalation of "very fine respiratory droplets and aerosol particles" is one of three ways that COVID-19 can be transmitted.

This means you may be able to contract COVID-19 through secondhand smoke if the person smoking is infected with the virus.

Although there's no evidence that smoke makes the virus travel farther, secondhand smoke can float 25 feet from its source. Dr. Onugha said there's no safe distance that can be recommended to protect someone when standing around cigarette smokers and advised wearing a face covering to minimize the risk of transmission.

Lung Disease and Secondhand Smoke

Even without containing virus particles, secondhand smoke is virulent, it's loaded with hundreds of toxic or carcinogenic chemicals. "Studies have shown associations of secondhand smoke with increased risk of lung cancer and cardiovascular disease, including heart attack and stroke," said Dr. Yoo. "Even short-term exposure to cigarette smoke can worsen pre-existing lung conditions, such as asthma and COPD," Dr. Yoo explained.

Chronic health conditions, including lung disease and heart disease, can make you more likely to get very sick if you become infected with COVID-19. So if you've developed these issues as a result of exposure to secondhand smoke, it can put you at risk of a severe COVID-19 infection.

COVID-19 Risk for Smokers

As for smokers themselves, research points to a heightened chance of serious disease if they contract COVID-19. In an observational study, researchers found that smokers were at greater risk of severe COVID-19 than people who had never smoked, including higher rates of hospitalizations and death.

Former smokers, too, are susceptible to severe COVID-19. In fact, a 2021 study suggested that people who quit were more likely to develop serious illness than current smokers. Another study published in the International Journal of Epidemiology echoed these findings.

A Quick Review

Smoking is a well-known risk factor for disease in general, and both the Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) caution that smoking is a risk factor for severe COVID-19. There is evidence to suggest that being around smokers, and inhaling secondhand smoke, may increase your risk for becoming infected with COVID-19. If you want to protect yourself from COVID-19, try to steer clear of second hand smoke from people who are infected, and if you can't avoid it, wear a mask.

The information in this story is accurate as of press time. However, as the situation surrounding COVID-19 continues to evolve, it's possible that some data have changed since publication. While Health is trying to keep our stories as up-to-date as possible, we also encourage readers to stay informed on news and recommendations for their own communities by using the CDC, WHO, and their local public health department as resources.