At the same time, health officials warned of a disturbing development:
Dozens of patients with vaping-related lung illness were rehospitalized shortly after discharge, and seven died after being discharged, suggesting that the illness must be closely monitored and may worsen in older patients with chronic conditions.
“We don’t know why they worsened so suddenly,” Schuchat said.
Of 1,139 hospitalized patients who were discharged by Oct. 31, 2019, 31 were readmitted to the hospital within about four days, on average, after initial discharge. The median age of those readmitted to the hospital was 27. The other seven patients died within about three days of initial discharge. They were more likely to have underlying conditions, such as heart disease, sleep apnea or diabetes, and they tended to be older, with a median age of 54.
[...]
Among the other findings, the reports show that the vaping-related outbreak
was a new phenomenon and not an illness that had gone unrecognized, Schuchat said. Emergency department visits increased sharply
beginning in June 2019 and peaked in September.
Since then, emergency room visits for vaping-related illnesses have declined, although new cases continue to be reported.
[...]
The report on vitamin E acetate offered
two theories for how the compound could harm the lungs. When vitamin E acetate is heated through vaping, that process can disrupt the material on the lining of the lungs, and that might interfere with the lungs’ ability to expand, Schuchat said. The second way could be a chemical injury from a byproduct that is released when vitamin E acetate is heated to very high temperatures. That byproduct, called ketene, could also provide “a possible mechanism by which vitamin E acetate could cause respiratory dysfunction,” the researchers wrote.
A study by Minnesota health officials also found that THC products seized by law enforcement officials
during 2018, before the outbreak, did not contain vitamin E acetate. But 20 out of 20 THC-containing products seized by Minnesota law enforcement authorities during September,
at the peak of the outbreak, contained vitamin E acetate.
CDC researchers noted that vitamin E acetate, which has a viscosity like that of pure THC oil, began to appear in the
black market in late 2018 or early 2019, and gained popularity in 2019. Industry sources have said black market operators used vitamin E acetate to cut THC oil to increase profits.
The Food and Drug Administration has said most of the THC vaping fluids linked to patients contain vitamin E acetate, with concentrations ranging from 23 to 88 percent. By contrast,
the FDA has found no vitamin E acetate in 197 nicotine products analyzed so far.
On Friday, the FDA and Drug Enforcement Administration seized 44 websites advertising the sale of
illegal vaping cartridges containing THC. Selling THC vaping products over the Internet is a violation of federal law, the agencies said. The move was part of Operation Vapor Lock, which is investigating the supply chain of vaping products associated with the lung injuries. So far, however,
none the advertised products has been linked to any cases of lung injury.