CBS, WarnerMedia, Viacom ban e-cigarette ads

CBS, WarnerMedia and Viacom have decided to ban Juul and other electronic cigarette ads in their networks following a wave of mysterious vaping-related illnesses that have claimed seven lives.

A spokesman for CBS confirmed to NBC News on Wednesday that it will not accept e-cigarette advertising on its network. WarnerMedia said it is not releasing e-cigarette ads from its TNT and TBS networks, both of which have published ads for Juul in recent weeks.

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

For the past two weeks, Viacom has also advertised for Juul on networks including BET, CMT, TV Land, and Paramount Network. Viacom told CNBC that they will no longer broadcast ads on e-cigarettes with immediate effect.

Many e-cigarette users are teenagers. More than 25 percent of seniors in high school and more than 20 percent of high schools said they had weapons during 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, both nicotine and THC are armed, the ingredient in marijuana that gives users a high.