Frank T. Leone, a pulmonologist who directs Penn’s Comprehensive Smoking Treatment Programs, is often asked to see patients in Penn’s hospitals who smoke. The hope is that Leone, who specializes in tobacco dependence, can persuade them to quit.

On Thursday, he saw a young man — a two-pack-a-day smoker — who had broken an ankle but was panicking about the threat the new coronavirus, which can cause fatal lung infections, poses to people whose lungs are already weakened by constant exposure to smoke or other noxious substances. “Doc, I don’t want to die,” he told Leone.

Leone said he’s meeting more patients who say they’d like to quit — now. Other doctors who treat lung patients and smokers have also seen a small uptick in interest. It remains to be seen, though, they said, whether that translates into action. In-person visits to smoking-cessation programs are currently on hold because of the virus.

“I think it’s a little bit early,” said Aditi Satti, a pulmonary critical care doctor who directs Temple Health’s smoking-cessation program. “People are just starting to wrap their heads around what’s happening around us.”

Ross Summer, chief of the section of allergy, pulmonary and critical care medicine at Sidney Kimmel Medical College of Thomas Jefferson University, said lung patients are calling about coronavirus whether they smoke or not. “People are extremely concerned and worried,” he said. He’s worried that some of them are forgoing routine doctor’s visits they really need because they’re afraid to leave their houses.

Satti said that, so far, studies have not shown that fear helps people quit cigarettes and stay off them.

The nature of cigarette addiction makes it hard to stop during a crisis, Leone said. Nicotine works in the part of the brain that detects threat. Rather than sedating, “it’s giving the brain the sort of all-clear, safe signal,” he said.

At a time like this, smokers know that they are at high-risk for trouble if they get COVID-19, the disease caused by the new coronavirus.

Unfortunately, their brains experience smoking cessation as a threat. And smoking is the thing that makes smokers feel less threatened. “The place that people go for a brief respite is their cigarettes,” Leone said.

This is why smokers tend to feel torn and say, “I’m going to stop, but not right now.”

Summer thinks all the scary news from the virus could make things worse. “This type of stress usually leads to more smoking,” he said.

Lung experts said there’s good reason to suspect that the new virus will be more dangerous to people who smoke or vape. Frequent exposure to other things that can harm the lungs, such as dust and pollutants, may also leave them less able to recover from infection.

Leone said about 20% of adults in Philadelphia smoke. Rates are in the low teens in the surrounding suburban counties.

The National Institute on Drug Abuse earlier this month cautioned that, “because it attacks the lungs, the coronavirus that causes COVID-19 could be an especially serious threat to those who smoke tobacco or marijuana or who vape.” Because far more men than women smoke in China, that might explain why more men have died there, the agency said.

So far, evidence about smoking and the new coronavirus is limited. A study by the Chinese Center for Disease Control found that the case fatality rate was 6.3% in people with chronic respiratory disease compared with the overall rate of 2.3%. (These rates are likely too high because they are based on cases doctors knew about, while they may never have seen people with mild disease.) Another small Chinese study of 78 patients with pneumonia found that smokers were 14 times more likely to deteriorate over two weeks than nonsmokers.

Summer said the lungs are the only organs that are always exposed to the outside through the air we breathe. Pollution, vaping, and cigarette smoke put them under increased stress. “In general,” he said, “smokers are more susceptible to pneumonia.”

Local lung experts said that smoking increases inflammation in the lungs, making them less likely to respond appropriately when faced with a viral onslaught. Tiny fibers called cilia that remove dirt, dust, and germs are damaged by smoke as are blood vessels important for oxygen distribution. Damage to the airway wall can also make it easier for bacteria to grow, said Gerard Criner, chair of thoracic medicine and surgery and director of the Temple Lung Center

Leone said that vaping causes many of the same cellular changes as smoking. “The physical assault on the lungs is virtually identical,” he said.

Chronic obstructive pulmonary disease (COPD) can develop after years of exposure to smoking. Criner said that one Italian study found that 26% of people who died of COVID-19 had COPD.

Deborah Brown, chief mission officer for the American Lung Association, said she cautions people who smoke tobacco or marijuana or who vape to take extra precautions and consider themselves at high risk for complications.

She hopes smokers will use the disruption in their work lives to create a new plan for quitting. The organization has a personalized online quitting program as well as a self-help guide. Staffers at 1-800-LUNG-USA can answer questions. The association also has an online support community through Inspire.com.

Like other smoking-cessation programs, Leone’s has had to cancel in-person meetings. He considers those most effective because they allow him to explore why clients smoke and create a stronger therapeutic relationship. He’s talking with people now by phone.

Satti, who also has had to stop smoking-cessation clinics, is urging people interested in quitting to visit the Pennsylvania Free Quitline.

Criner said “there’s always a benefit to stopping smoking even if you smoked a long time.” He said it will decrease mucus production as well as flare-ups of COPD. One study found that stopping smoking for 10 to 14 days improved postoperative complications.

It’s too soon to know how it will affect response to the new coronavirus.