CHICAGO, Dec. 7 (Xinhua) -- It is not likely that a single e-cigarette brand caused the national outbreak of vaping-related lung diseases reported across the United States, according to a report released by the U.S. Centers for Disease Control and Prevention (CDC) late Friday.

Dank Vapes were the most commonly reported THC-containing product used by patients nationwide, although there are regional differences, the CDC said in the report. However, rather than a licensed product coming from one business, Dank is a class of largely counterfeit THC-containing products of unknown origin.

CDC recommends that people should avoid vaping any products that contain THC, "particularly from informal sources like friends, family, or in-person or online dealers."

Vitamin E acetate, a thickening agent used in some vaping products, is likely to be associated with EVALI, which refers to "e-cigarette, or vaping, product use associated lung injury." However, "many substances and product sources are being investigated, and there might be more than one cause," said the CDC in its report.

As of Dec. 3, a total of 2,291 hospitalized EVALI cases had been reported to CDC from all 50 states, the District of Columbia, Puerto Rico and U.S. Virgin Islands. And 48 deaths had been confirmed in 25 states and the District of Columbia.