Some Canadian doctors admit an Ontario teenager's brush with death from a lung disease this year highlights just how little we know about the effects of vaping. Thursday's Canadian Medical Association Journal contains an article by six doctors who treated the 17-year-old boy during a 47-day hospital stay. They say the boy went from being in perfect health to being on life support and narrowly averting a double-lung transplant, after just five months of regularly using e-cigarettes. Dr. Simon Landman with the London Health Sciences Centre helped care for the teen. Landman says the teen's condition resembled "popcorn-lung" damage usually seen in factory workers forced to breathe in toxic chemicals. The boy has been out of hospital for months, but still hasn't recovered full breathing function.