CBS, WarnerMedia, and Viacom have decided to ban Juul and other electronic cigarette advertisements on their networks following a surge of mysterious vaping-related diseases that has claimed the lives of seven people.

A CBS spokesperson confirmed to NBC News on Wednesday that it will not accept any e-cigarette advertising on its network. WarnerMedia said it's dropping e-cigarette ads from its networks TNT and TBS, which have both run ads for Juul in recent weeks.

"Given warnings from the CDC, the AMA and the American Lung Association to consumers, our company has revised its policies regarding e-cigarette advertising, and will no longer accept advertising for this category," WarnerMedia said in a statement on Wednesday. "We will continue to monitor the investigations by relevant medical agencies and may re-evaluate our position as new facts come to light."

Viacom has also advertised for Juul in the past two weeks on networks including BET, CMT, TV Land, and Paramount Network. Viacom told CNBC that it will no longer air ads regarding e-cigarettes effective immediately.

Many e-cigarette users are teenagers. More than 25 percent of high school seniors and more than 20 percent of high school sophomores said they'd vaped within the past month.

The Centers for Disease Control and Prevention reports that at least seven people have died and more than 400 people are suffering from a mysterious lung disease believed to be linked to vaping. In many cases, patients vaped both nicotine and THC, the ingredient in marijuana that gives users a high.

The outbreak is prompting lawmakers to demand stricter regulation for e-cigarettes. A week ago, the Trump administration announced plans to ban flavored e-cigarettes. New York officially became the first state to ban the sale of flavored e-cigarettes on Tuesday, citing the increasing health concerns.

Juul did not immediately respond to a request for comment on Wednesday.