By Manas Mishra and Saumya Joseph
(Reuters) - People should stop using e-cigarettes, especially those with marijuana ingredient tetrahydrocannabinol (THC), U.S. public health officials recommended on Friday, as an investigation into illnesses and deaths related to vaping deepens.
E-cigarettes have been marketed as tools to help smokers quit, but rising use among youth in the United States and a spate of severe lung illnesses tied to the devices have triggered a backlash and heightened regulatory scrutiny.
The U.S. Centers for Disease Control and Prevention has in the past advised consumers to avoid the devices, but the latest recommendation focused on THC products follows nationwide data that pointed to a large number of cases related to the use of the high-inducing component of marijuana.
The CDC and state health officials, along with other health agencies, are investigating 805 confirmed and probable cases and 12 deaths so far from a mysterious respiratory illness tied to vaping, as of the latest update on Thursday.
According to the research published by CDC on Friday, 514 of the 805 patients knew about substances used in their vaping products, with nearly 77% using THC-containing vapes.
However, this does not narrow the focus of the investigation as some users have also reported using e-cigarettes with just nicotine, CDC's principal deputy director Anne Schuchat told reporters on Friday.
The data showed that 56.8% used nicotine in their vapes, while 16% used vapes containing just nicotine in the 30 days preceding their symptoms.
"We do not know yet what exactly is making people sick, for example, whether particular solvents or adulterants are leading to lung injury, or whether cases stem from a single supplier or multiple ones," Schuchat said.
Separate data from Wisconsin and Illinois showed that although no single brand name was reported by all patients, two-thirds of consumers reported using a prefilled THC cartridge under the brand name "Dank Vapes".
A study published in the New England Journal of Medicine earlier this month found that more than half of lung illness patients extensively interviewed in Wisconsin and Illinois reported having used the "Dank Vapes" brand.