Teen and young adult vapers were up to 7 times more likely to get COVID-19, compared with non-vapers, the study found.

Vaping may increase the risk of getting COVID-19, at least in teens and young adults, a new study suggests.

Among those tested for COVID-19, e-cigarette users were five times more likely to be diagnosed with COVID-19, and those who used both e-cigarettes and traditional cigarettes ("dual users") were seven times more likely to be diagnosed with COVID-19, compared with those who did not use e-cigarettes or traditional cigarettes.

In addition, dual users were nearly five times more likely to report experiencing symptoms of COVID-19 at the time of the survey, regardless of whether they were tested, compared with non-users.

Both smoking and vaping are known to damage the lungs and affect the immune system, which may increase the risk of developing a COVID-19 infection after exposure to the virus, according to NBC.

However, the study only found an association between vaping and COVID-19 infection, and cannot prove that vaping led to the illness.

But the study did take into account a number of factors that could infuence participants' risk of infection, such as their self-reported compliance with shelter-in-place orders and the rate of COVID-19 diagnoses in their state, as well as their age, sex, race/ethnicity, body mass index and socioeconomic status.

The letter cites the current study as evidence that vaping is a risk factor for COVID-19.