The COVID-19 pandemic has overshadowed followup to 2019's outbreak of e-cigarette or vaping product use-associated lung injury (EVALI) cases. But the Centers for Disease Control and Prevention did issue a final update on the nationwide case total in February, tallying 2,807 EVALI hospitalizations nationwide and 68 confirmed deaths in 29 states and Washington, D.C. And research into pulmonary vaping illnesses continues, with Ohio State University receiving a $5.5 million grant from the American Heart Association to study EVALI in July.
The CDC reports a consistent decline in EVALI cases since September 2019, and identifies vitamin E acetate — a vaping additive used to dilute marijuana oils — as the primary cause. Use of Vitamin E acetate is predominantly relegated to black-market vape products, a conclusion backed by the Yale study, which dove into state totals of EVALI cases in 12- to 64-year-olds.
According to the study, Delaware, Utah and seven connected Midwestern states — Illinois, Indiana, Iowa, Minnesota, North Dakota, South Dakota and Wisconsin — accounted for a "high-prevalence cluster" of EVALI cases, or 25 to 114 cases per 100,000 residents. Meanwhile, the first five states to legalize recreational marijuana — Alaska, California, Colorado, Oregon and Washington — each had under one recorded case per 100,000 residents. As study author and Yale School of Public Health Assistant Professor Abigail Friedman points out, none of the states with high EVALI rates had legal marijuana markets in 2019.
"If e-cigarette or marijuana use per se drove this outbreak, areas with more engagement in those behaviors should show a higher EVALI prevalence," she says in a statement. "This study finds the opposite result. Alongside geographic clusters of high EVALI prevalence states, these findings are more consistent with locally available e-liquids or additives driving the EVALI outbreak than a widely used, nationally-available product."
The Yale study argues that banning marijuana and nicotine vaping products, both of which became increasingly popular from 2015 to 2019, leads to a larger presence of black-market and informally sourced vape products that are made without regulations.
"If the goal was to reduce EVALI risks, the study suggests that those policies may have targeted the wrong behavior," Friedman notes, adding that established, regulated nicotine and marijuana markets "may have crowded out use of riskier, informally sourced e-liquids."
Efforts to ban the sale of flavored nicotine products at the Colorado Legislature and Denver City Council failed earlier this year, but Boulder began prohibiting flavored nicotine vaping products last October, and the Loveland City Council is currently considering a similar ordinance.
As of January 2020, eight EVALI cases have been reported in Colorado.
Earlier this month, a national CDC survey showed that under 20 percent of high school students and around 5 percent of middle school students admitted to recent vaping, down from 28 percent of high-schoolers and 11 percent of middle school students in 2019.
Update: This article was updated on September 14 to correct an error stating that vitamin E acetate is mixed with nicotine vaping oil.