Patients hospitalized in 8 Minnesota vaping cases used THC

State and federal health investigators are focusing on illicit THC compounds as they search for the cause of a rash of vaping-related respiratory illnesses that struck teens and young adults this summer.

Health officials have interviewed eight of 15 patients in Minnesota who have been hospitalized for severe respiratory illnesses with confirmed links to vaping. All inhaled THC, the psychoactive compound in marijuana that creates a sensation of being high, said Richard Danila, epidemiology program manager for the Minnesota Department of Health.

"True for Minnesota: All of the ones we've interviewed, eight of eight, said they used an illegal THC product," Danila said Tuesday.

Another nine hospitalizations for respiratory injuries have been reported to the state, but investigators haven't confirmed their links to vaping yet, either by interviewing the patients or reviewing their medical records.

Nationally, more than 200 similar cases have been reported this summer, though not all have been confirmed as vaping-related.

In Minnesota, the hospitalized patients ranged in age from 16 to 23. At least seven suffered such severe injuries that they required intensive care, and four needed to be intubated and placed on ventilators to breathe.

State health officials have warned teens in the past about vaping with legal nicotine products because of the lack of regulation over their contents and because harmful metals and other substances have been found in some vaping liquids. However, those products do not appear to be the problem in this outbreak, though many of the injured teens vaped both THC and nicotine before they were hospitalized.

Not all patients nationally have admitted to vaping illicit THC products, but Danila said that could be because they didn't know, or don't want to admit it. He acknowledged it has taken time to build trust with the injured Minnesota teens and assure them that information provided to the Health Department for this investigation can't be turned over to law enforcement agencies.

"You can think about how difficult this investigation is," he said. "You have a 17-year-old in the ICU. Are they going to tell you they used an illegal product? Are they going to tell you they used an illegal product when mom or dad are standing in the same room?"

None of the injuries so far has involved people who exclusively vaped legal THC products obtained from authorized medical marijuana distributors, Danila said. In many instances, the teens suffered anxiety or mental disorders and vaped illicit substances as a form of self-medication, he noted.

As the probe continues, investigators hope to examine the product types the patients vaped and the delivery systems that they used to identify a common cause of the injuries — and one death reported in Illinois.

At least three hospitalized patients in Minnesota provided samples of their THC products for testing by federal authorities. Danila said the state health lab is preparing to conduct its own testing as well to hasten the search for the cause of the injuries.