She had decided that day to put down the vaping device, but it was already too late.

After vaping for two years as an alternative to smoking cigarettes, 17-year-old Whitney Livingston came down with a fever that landed her on life support, her mother told

“She could have almost died,” Jennifer Audas told Fox4News about her daughter. “And her oxygen had already dropped all the way. There was pneumonia in both lungs. The doctor said that it looked like no pneumonia he’d ever seen.”

Livingston’s illness comes as health officials scramble to understand a wave of serious lung diseases afflicting more than 450 otherwise healthy people who use e-cigarettes, which mimic smoking by heating liquids with substances such as nicotine or marijuana. Six deaths have been attributed to vaping, and the Trump administration on Wednesday said it would move to ban most flavored e-cigarettes.

Livingston, a high school senior who works as a restaurant hostess, is being treated at a hospital in Dallas after she became sick about two weeks ago, Fox4News reported. At first, the report says, her symptoms resembled those of a stomach virus: a fever, a cough and rapid breathing.

She immediately knew what was happening. Livingston had read about a spate of vaping-related illnesses and deaths across the country, Fox4News reported, and she understood the risks of using the e-cigarettes. Doctors, however, are not sure that vaping caused Livingston’s illness, CBS Dallas/Fort Worth reported.

Audas told Fox4News that when her daughter revealed she had been smoking cigarettes, Audas had thought vaping would be a better alternative.

“You think: cigarettes, you’re going to get cancer, so this is much healthier,” Audas told Fox4News. “Because that’s the way it’s portrayed.”

Livingston’s health is improving, the news station reported, but the family is unsure of what lies ahead for her.

Although e-cigarettes have been on the market for more than a decade, reports of illnesses accelerated this year after patients reported coughing, chest pain or shortness of breath. Many people have been diagnosed with acute respiratory distress syndrome, a life-threatening condition in which fluid builds up in the lungs.

As The Washington Post’s Hannah Knowles previously reported:

Officials are still trying to figure out what, exactly, is causing people to fall ill. They think chemicals are to blame.
“The focus of our investigation is narrowing, and that is great news, but we are still faced with complex questions in this outbreak that will take time to answer,” said Ileana Arias, CDC acting deputy director for noninfectious diseases.
The nationwide investigation has found no particular vaping devices or products linked to all cases and is looking into potential contamination or counterfeit, as many victims report buying marijuana on the street rather than from a store.

The popularity of vaping has soared in recent years as young people in particular take to the practice. More than half of users are younger than 35 years old, according to a study published in the Annals of Internal Medicine.

Under the Trump administration’s proposal, the Food and Drug Administration would require companies to stop selling most flavored e-cigarettes until the FDA potentially approves them. Manufacturers of tobacco-flavored vaping devices would not have to come off the market and would have until May to file for approval.

Michigan last week became the first state to ban flavored vaping devices, and New York Gov. Andrew M. Cuomo (D) has promised to introduce a similar bill.

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