Health officials are investigating more cases of a breathing illness associated with vaping.

While the cause remains unclear, officials said Friday that many reports involve e-cigarette products that contain THC, the mind-altering substance in marijuana.

Officials from the Centers for Disease Control and Prevention said Friday they are looking at 215 possible cases across 25 states. According to data collected from state health departments by NBC News, at least 298 people have been hospitalized nationwide with severe lung disease apparently related to vaping.

In addition to breathing difficulties and lung damage, some people have reported vomiting, diarrhea and fatigue.

The CDC has not identified one common product, but the CDC and Food and Drug Administration warned the public not to buy vaping products off the street.

The FDA is analyzing the content of dozens of vaping samples collected by state health authorities investigating the illness.

Pulmonary specialist Dr. Panagis Galiatsatos said that while it’s good the CDC is cautioning certain groups of people to avoid e-cigarettes, the warning should have also been directed to everyone using the products.

“I would plead with the CDC to take a harsher approach,” said Galiatsatos, an assistant professor in the division of pulmonary and critical care medicine and director of the Tobacco Treatment Clinic at Johns Hopkins Medicine. “I would recommend everyone stop using these products until more is known.”

The hundreds of cases of vaping-related lung illnesses “could be the tip of the iceberg,” Galiatsatos said, noting that there may be many more people who are experiencing symptoms but not severe enough to send them to the emergency room.

He said he has had “half a dozen” younger patients come in for help quitting e-cigarettes because of lung symptoms.

“These were otherwise healthy teens who were feeling short of breath,” Galiatsatos said.

Exposure to secondhand vapor

The impact of e-cigarettes may not be limited to users, experts say.

Galiatsatos had a patient who developed breathing problems that appeared to be linked to regular exposure to secondhand vapors. When the patient’s significant other cut back on vaping, the breathing symptoms improved, Galiatsatos said.

A study published in JAMA Network Open this week suggested that exposure to secondhand chemicals emitted by e-cigarettes is on the rise among middle- and high-school students. That study, based on a survey of tens of thousands of teens, found that secondhand exposure had risen from 1 in 4 in 2015 to 1 in 3 in 2018.

There is evidence from another report published in Chest in January that secondhand vapors can worsen symptoms in people who already have breathing issues, said the lead author of the secondhand vaping study, Andy Tan, an assistant professor in social and behavioral sciences at the Dana Farber Cancer Center and the Harvard T.H. Tan School of Public Health.

The Chest study “found that youth with pre-existing asthma exposed to secondhand aerosols reported acute exacerbation of their asthma,” Tan said.

In some cases people might not even know they have been exposed to secondhand vapors.

“With newer vaping devices producing less visible vapor you might not see them like you would with traditional cigarette smoke — until you get a whiff of mango or mint and wonder where the fragrance is coming from,” Tan said.

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