The new vaping number: 530. That's how many people nationwide have been diagnosed with lung illnesses linked to e-cigs, up from 380 last week, reports the AP.
Health officials still can't pinpoint a cause—or perhaps multiple causes—but the FDA has now begun an investigation of its own alongside the CDC's inquiry, reports the Washington Post.
The latest CDC update also included stats showing that young men are the most common victims. Of those affected, about three-quarters are male and two-thirds are between 18 and 34, reports the New York Times.
More than half the cases involve patients younger than 25.
“I wish we had more answers,” says Dr. Anne Schuchat of the CDC, adding that the death toll will surely rise from the current seven because some of the lung illnesses being monitored are severe.
One potential clue is that most of those affected used a product with THC, the active ingredient in marijuana, and many of them bought it on the black market.
Health authorities say that's particularly dangerous, because street sellers might be cutting the THC with potentially dangerous agents, such as vitamin E acetate. (Two brothers who allegedly ran a large, illicit vaping operation were arrested.)
This article originally appeared on Newser: Vaping Illnesses Rise Sharply Again as FDA Joins Probe