(CNN) In a letter to the US Food and Drug Administration, lawmakers are urging the agency to temporarily clear the market of all e-cigarettes for the duration of the coronavirus crisis.
The letter, sent to FDA commissioner Dr. Stephen Hahn on Tuesday, makes this call based on emerging research that suggests vaping or using e-cigarettes can come with an increased risk of being diagnosed with Covid-19 and suffering symptoms.
"This is true in vapers as young as 13, which is particularly concerning, given that young people are increasingly driving the spread of COVID-19, threatening the health and safety of Americans of all ages," wrote Rep. Raja Krishnamoorthi (D-IL), chairman of the House Committee on Oversight and Reform's Subcommittee on Economic and Consumer Policy, who sent the letter on behalf of the subcommittee.
In the letter, the subcommittee asks for Hahn to confirm by August 18 -- in one week -- whether or not the FDA will temporarily clear the market of all e-cigarettes.
Considering that the world still doesn't know much about the novel coronavirus that causes Covid-19 -- and that the vaping trend emerged just recently -- not much is known about how the two may affect each other or be associated.
But some new studies have started to explore possible connections, specifically around how vapers might have a more difficult time fighting off a coronavirus infection and could possibly be more susceptible to the illness.
Being diagnosed with Covid-19 was five times more likely among young people who have used e-cigarettes ever, according to a new study that is referenced in Krishnamoorthi's letter.
The study, based on an online survey, also found that young people who have a history of using both e-cigarettes and traditional cigarettes were seven times more likely to be diagnosed with Covid-19 compared with those who have never used either product.
"We thought that we'd see some relationship. We did not expect to see a five to seven times more likely relationship. That's huge," said Bonnie Halpern-Felsher, professor of pediatrics and director of research in the division of adolescent medicine at Stanford University in California, who led the new study.
The study, published in the Journal of Adolescent Health on Tuesday, also found in its survey that respondents who reported vaping in the past 30 days were 2.6 times more likely to be tested for Covid-19.
"About half of the sample was sheltering in place -- because we did ask that -- but that doesn't mean they're not in the backyard with a friend sharing their vaping product," Halpern-Felsher said, adding that this increased risk to be diagnosed with Covid-19 could be tied to exposure to the coronavirus from sharing products, touching your face more or possibly breathing in droplets containing the virus through the aerosols of an e-cigarette. More research is needed.
"We don't know. These are hypotheses," Halpern-Felsher said. "I actually think it's all of the above."
The study included data on 4,351 young people ages 13 to 24 in the United States who completed an online survey in May.
The survey asked them questions about using e-cigarettes and traditional cigarettes, along with Covid-19-related symptoms, getting tested and being diagnosed with the disease.
"We've seen adolescents who are vaping having asthma. We've seen seizures. We've seen bronchitis, pneumonia, hospitalizations, lung collapsing and now we're seeing Covid," Halpern-Felsher said about the study results.
The study comes with some limitations, including that it was based on self-reports from anonymous online survey responses -- which can be vulnerable to biases if respondents don't give honest answers.
Overall, Halpern-Felsher said that there is a message for young people and health care providers in the survey findings.
"This is a real call for adolescents to stop using e-cigarettes -- to stop using any inhaled product -- to stop putting things into their lungs that hurt their lungs," she said. "There's a message for healthcare providers and it's a message for parents: talk to your teens."
Dr. Brian Williams, an internal medicine and pediatric hospitalist at UW Health and researcher at the University of Wisconsin Center for Tobacco Research and Intervention, called the new study's findings "concerning" -- and added that it gives more reason to quit smoking or vaping.
"When you do a study like this you're trying to look for a signal. Is there a connection between e-cigarette use and smoking and a Covid-19 diagnosis? And it sure looks like they got a pretty strong signal," said Williams, who was not involved in the study. An area that now warrants further study, he said, is why there might be this association between vaping and Covid-19.
"Is it something about the actual ritual of bringing your hand to your face? Are you bringing germs to your face? Is it the result of sharing vaping devices or sharing cigarettes? Or is it something about how smoking or how vaping is causing inflammation in your respiratory tract or affecting your immune system so that it's more susceptible to infection?" Williams said. "Those things are unclear at this point."
While there are many questions left to answer, a separate study recently explored just how many young adults might be at this increased Covid risk due to vaping or other risk factors.
Nearly a third of young adults have some type of risk factor that makes them medically vulnerable to severe illness if they get Covid-19, and smoking -- including using either traditional cigarettes or vaping e-cigarettes -- is the strongest risk factor among this age group, according to a study published in the Journal of Adolescent Health in July.
The researchers, from the University of California, San Francisco, looked at more than 8,000 participants ages 18 to 25 who had participated in the National Health Interview Survey to see what their medical vulnerability to severe Covid-19 was in relation to risk indicators that had been set out by the US Centers for Disease Control and Prevention, including health conditions and smoking habits.
The researchers found 32% of the total study population were medically vulnerable for severe Covid-19. However, when the group of participants who smoked cigarettes or e-cigarettes were taken out of the analysis, the medically vulnerable percentage decreased by half, to 16%.
"This difference between estimates is driven largely by the sizable portion of young adults who reported that they engaged in past 30-day smoking (1 in 10) and past 30-day e-cigarette use (1 in 14)," the researchers wrote in their study. "By contrast, relatively fewer young adults reported medical conditions identified by the CDC as conferring severe illness risk."
The research showed that in the whole study population, young adult men were at a higher risk for severe Covid-19. Although more women reported having asthma and immune conditions, higher rates of smoking in men overrode this. However, looking at just the nonsmokers, women had a higher risk.
People who smoke traditional cigarettes have 1.91 times the odds of their Covid-19 progressing to a more severe illness than people who have never smoked, according to a paper published in the journal Nicotine & Tobacco Research in May.
For that paper, other researchers from the University of California, San Francisco, reviewed and analyzed 19 previously published studies on the association between smoking and Covid-19. Those studies included data on a total of 11,590 Covid-19 patients. None of the studies assessed e-cigarette use.
In their review of those studies, the researchers found that 29.8% of the Covid-19 patients who had a history of smoking experienced their Covid-19 illness progress to a more severe disease compared with only 17.6% of non-smoking patients.
In their paper, the researchers called on physicians and public health professionals to collect data on smoking and e-cigarette use as part of clinical assessments among Covid patients.