COLUMBUS, Ohio - Cough, shortness of breath and fatigue can be the first symptoms in people who have been hospitalized with severe lung damage likely due to vaping. All the patients have a history of vaping, but doctors can’t find any infections. Therefore, public health officials suspect the cause of the illnesses is chemical exposure, likely due to their e-cigarette use. But what exactly is that chemical? Does it come from vaping nicotine or THC, the active ingredient in marijuana? What about flavors? Details seem as clear the clouds that vapers create. But some information has been gleaned by public health officials. Read on for more. A: A review of cases in Wisconsin and Illinois was published in the New England Journal of Medicine. It found people who became sick reported vaping nicotine, THC and cannabidiol or CBD products. CBD is an ingredient in marijuana and hemp that doesn’t produce a high but is thought to have medicinal benefits. “It doesn’t mean nicotine is safe, but a lot of these patients vaping THC is a concern,” said Joanna Tsai, a physician and researcher who studies vaping at Ohio State University. James Jarvis, president of the Ohio Vapor Trade As...