Health officials in London, say a high-school-aged youth was on life support after smoking e-cigarettes, but has since recovered.
The Middlesex-London Health Unit says the youth was in the intensive care unit with a severe pulmonary illness.
The vaping-related illness was first reported today and is believed to be the first confirmed case in Canada.
Health officials in the United States have been investigating a mysterious surge of severe breathing illnesses linked to vaping marijuana in recent months.
They have identified 380 confirmed and probable cases in 36 states and one territory, including at least six deaths.
Health Canada has been urging people who vape to watch for symptoms such as a cough, shortness of breath, fatigue, diarrhea, vomiting and chest pain.