Outbreak of pulmonary diseases linked to vaping

Over the past two months, vaping has been associated with more than 450 cases of severe pulmonary disease in the United States. Cases have been detected in 30 US states, including several deaths.1 Primary clinical features include respiratory symptoms such as cough, shortness of breath, or chest pain. Some cases also include gastrointestinal symptoms (nausea, vomiting, or diarrhoea), as well as non-specific constitutional symptoms (fatigue, fever, or weight loss). All cases reported using e-cigarettes before the onset of symptoms.

The outbreak has caused alarm among public health authorities, and renewed questions about the safety of vaping. To date, much of the literature on the health effects of vaping has focused on the relative risk compared with smoking.2 There is now strong consensus that vaping is substantially less harmful than smoking, and smokers who switch exclusively to vaping have the potential to …