TENNESSEE, USA — There are now 26 cases of vaping-related illnesses reported in Tennessee, the Centers for Disease Control and Prevention said Thursday. 

Nationwide, the CDC said 530 confirmed and probable vaping illness cases have been reported in 38 states and one U.S. territory. Those numbers are up from 380 a week ago.

More than half of the reported illnesses are in people under the age of 25.

The agency said seven people have died from vaping-related illnesses. 

Meanwhile, the Food and Drug Administration revealed that its criminal investigations unit started tracking leads early on. The agency's tobacco director, Mitch Zeller, stressed that it is not interested in prosecuting individuals who use illegal products but is lending a hand because of the unit's "special skills."

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All patients had used an electronic cigarette or another vaping device.

Doctors have said the illnesses resemble an inhalation injury, with the lungs apparently reacting to a caustic substance. So far, no single vaping product or ingredient has been linked to the illnesses, though most patients reported vaping THC, the high-producing ingredient in marijuana.

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