Authorities in the United States are investigating around 150 cases of severe pulmonary disease which they believe could be linked to e-cigarette use or vaping.
Between 28 June and 20 August, at least 149 possible cases of severe lung illness associated with e-cigarette product use were reported by 15 states, primarily among adolescents and young people.
According to the Centers for Disease Control and Prevention (CDC), in many of the cases, patients reported a gradual start of symptoms including breathing difficulty, shortness of breath and/or chest pain before hospitalisation. Some cases additionally reported mild-to-moderate gastrointestinal illness and fatigue.
In a statement, the CDC said available evidence does not suggest that an infectious disease is the principle cause of the illness. While a cause has not yet been identified, all reported cases had used e-cigarette products or had been vaping.
It also noted that in many cases, patients acknowledged the recent use of tetrahydrocannabinol-containing products; however, it said no specific product has been identified in all cases, nor has any product been conclusively linked to illnesses.
“Even though cases appear similar, it is not clear if these cases have a common cause or if they are different diseases with similar presentations,” the CDC said.