On January 14, 2020, this report was posted online as an MMWR Early Release.

While the investigation continues, CDC recommends that the best way for persons to ensure that they are not at risk is to consider refraining from the use of all e-cigarette, or vaping, products.

Nationwide, most EVALI patients with data on product source reported acquiring THC-containing products from only informal sources, whereas most nicotine-containing products were acquired from commercial sources. EVALI patients aged 13–17 years were more likely to acquire both THC- and nicotine-containing products from informal sources than were adults.

CDC, the Food and Drug Administration (FDA), state and local health departments, and public health and clinical stakeholders continue to investigate a nationwide outbreak of e-cigarette, or vaping, product use–associated lung injury (EVALI) (1). EVALI patients in Illinois, Utah, and Wisconsin acquired tetrahydrocannabinol (THC)-containing products primarily from informal sources (2,3). This report updates demographic characteristics and self-reported sources of THC- and nicotine-containing e-cigarette, or vaping, products derived from EVALI patient data reported to CDC by state health departments. As of January 7, 2020, among 1,979 (76%) patients with available data on substance use, a total of 1,620 (82%) reported using any THC-containing products, including 665 (34%) who reported exclusive THC-containing product use. Use of any nicotine-containing products was reported by 1,128 (57%) patients, including 264 (13%) who reported exclusive nicotine-containing product use. Among 809 (50%) patients reporting data on the source of THC-containing products, 131 (16%) reported acquiring their products from only commercial sources (i.e., recreational dispensaries, medical dispensaries, or both; vape or smoke shops; stores; and pop-up shops), 627 (78%) from only informal sources (i.e., friends, family, in-person or online dealers, or other sources), and 51 (6%) from both types of sources. Among 613 (54%) EVALI patients reporting nicotine-containing product use with available data on product source, 421 (69%) reported acquiring their products from only commercial sources, 103 (17%) from only informal sources, and 89 (15%) from both types of sources. Adolescents aged 13–17 years were more likely to acquire both THC- and nicotine-containing products from informal sources than were persons in older age groups. The high prevalence of acquisition of THC-containing products from informal sources by EVALI patients reinforces CDC’s recommendation to not use e-cigarette, or vaping, products that contain THC, especially those acquired from informal sources. Although acquisition of nicotine-containing products through informal sources was not common overall, it was common among persons aged <18 years. While the investigation continues, CDC recommends that the best way for persons to ensure that they are not at risk is to consider refraining from the use of all e-cigarette, or vaping, products.

This report updates patient demographic characteristics, self-reported substance use, and e-cigarette, or vaping, product sources reported to CDC as of January 7, 2020. States and jurisdictions voluntarily report data on confirmed and probable hospitalized or deceased EVALI patients to CDC weekly using established case definitions* and data collection tools.† Data on substance use and product source were collected from EVALI patients or their proxies (e.g., family members) via standard interview. Commercial product sources were defined as recreational or medical dispensaries, vape or smoke shops, stores, and pop-up shops. Informal sources were defined as friends, family, in-person or online dealers, or other sources. Severe clinical course was defined as hospital stay of ≥10 days; admission to an intensive care unit; requirement for endotracheal intubation, continuous positive airway pressure, or bilevel positive airway pressure; or death. All analyses were conducted using R software (version 3.6; R Foundation for Statistical Computing). The association of age group and product source was tested using Fisher’s exact test, with p-values <0.05 considered statistically significant.

As of January 7, 2020, among 1,979 (76%) patients with substance use data available, 1,620 (82%) reported using any THC-containing e-cigarette, or vaping, products, and 665 (34%) (i.e., 41% of patients reporting any THC-containing product use) reported exclusive use of these products (Table). Among patients reporting any THC-containing product use, 865 (53%) had data on frequency of use; 641 (74%) reported daily use, and 122 (14%) reported using these products a few times per week. Among EVALI patients reporting any THC-containing product use, 809 (50%) reported product source, including 131 (16%) who reported acquiring products from only commercial sources, 627 (78%) from only informal sources, and 51 (6%) from both sources. The most common sources reported for THC-containing products were family members or friends (38%), followed by dealers (31%), and other sources (23%). Medical dispensaries were reported as a source for THC-containing products by 3% of EVALI patients and recreational dispensaries by 8% of EVALI patients.

Overall, 1,128 (57%) patients reported using any nicotine-containing products, and 264 (13%) (i.e., 23% of patients reporting any nicotine-containing product use) reported exclusive use of these products. Among 681 (60%) patients with data available on frequency of nicotine-containing product use, 580 (85%) reported daily use, with a similar percentage among exclusive (84%) users. Among EVALI patients reporting use of any nicotine-containing product, 613 (54%) reported product source, including 421 (69%) who reported acquiring products from only commercial sources, 103 (17%) from only informal sources, and 89 (15%) from both sources. Among EVALI patients reporting use of any nicotine-containing products, the most commonly reported sources for nicotine-containing products were vape or smoke shops (48%), stores (43%), and family members or friends (15%).

Younger age was significantly associated with acquiring THC-containing and nicotine-containing products through informal sources (Figure 1). Among EVALI patients reporting use of any THC-containing products, 122 of 130 (94%) of those aged 13–17 years acquired products through only informal sources, compared with 42 of 68 (62%) of those aged 45–77 years (p<0.001). Among EVALI patients reporting use of any nicotine-containing products, 46 of 109 (42%) of those aged 13–17 years acquired products through only informal sources, compared with five of 43 (12%) of those aged 45–75 years (p<0.001).

The percentage of EVALI patients in each state acquiring THC-containing products from informal sources varied (Figure 2). Alaska, Hawaii, Idaho, Iowa, Mississippi, Montana, Oklahoma, Rhode Island, South Dakota, and Vermont had the highest percentages of patients acquiring THC-containing products from informal sources (50–100%). The percentage of EVALI patients acquiring nicotine-containing products from informal sources also varied by state, with Nevada having the highest percentage (57%).