What happens when public health officials tell people to be on the lookout for respiratory conditions that might be related to "vaping"? They get a lot more cases, less clarity about what is going on, and a handy propaganda weapon to deploy against potentially lifesaving products they irrationally dislike.

Since early last week, when a couple dozen cases of breathing problems following vaping had been reported in Illinois, Minnesota, and Wisconsin, the number has climbed into the triple digits. According to an August 23 update from the Centers for Disease Control and Prevention (CDC), "193 potential cases of severe lung illness associated with e-cigarette product use had been reported by 22 states." Those cases include the first reported fatality, which happened in Illinois.

"The Illinois patient's death was disclosed during a news conference held by officials at the Centers for Disease Control and Prevention, the Food and Drug Administration and the state of Illinois," The New York Times reports. "They did not provide details about the patient's identity, saying only that the person was an adult who had vaped recently and then succumbed to a severe respiratory illness. Health officials did not say what product the patient had used, whether an e-cigarette or other vaping device; nor did they specify what substance was vaped."

We likewise do not know exactly what the other patients were vaping, or even whether it was actually the cause of their symptoms. We do know that many of these patients, in Illinois and elsewhere, were vaping black-market cannabis extracts, which may have been contaminated by dangerous chemicals or may have contained synthetic cannabinoids rather than the real thing. We also know that many patients were using refillable vaping systems rather than disposable e-cigarettes or pod-loaded products like Juul. But we don't know whether they were filled with store-bought e-liquid, DIY mixtures, or mysterious fluids purchased on the black market. In this context, it is more than a little misleading to say these cases involve "e-cigarettes" or "vaping"—terms that most people will understand as referring to commercially produced nicotine delivery devices.

Scott Gottlieb, former head of the Food and Drug Administration (FDA), does not think these respiratory illnesses are linked to legally produced e-cigarettes. "The legal vapes have been actively regulated by FDA since Aug 2017," he wrote on Twitter this week. "FDA has conducted thousands of inspections of manufacturers and vape stores, published manufacturing guidance, sought product removals etc. These tragedies point to illegal vapes and THC."

Boston University public health professor Michael Siegel elaborated on the cannabis angle in a recent National Review piece. "In at least some of the cases," he notes, "the use of a THC oil, such as butane hash oil, has been implicated. In January of this year, there was a published case report of a severe, acute respiratory illness attributable to the use of butane hash oil. All 21 cases reported in California were apparently attributed to vaping marijuana, with all the THC e-liquids being purchased on the street."

Last week, the National Organization for the Reform of Marijuana Laws (NORML) warned cannabis consumers to be wary of black-market products. "Unregulated illicit market cannabis products, like products in any unregulated marketplace, are of variable quality and may put some consumers at risk," said Paul Armentano, NORML's deputy director. "These incidents linked to the use of unregulated, illicit market vapor cartridges reinforce the need for greater market regulation, standardization, and oversight—principles which NORML has consistently called for in the cannabis space. Consumers must also be aware that not all products are created equal; quality control testing is critical and only exists in the legally regulated marketplace."

That problem has nothing to do with legally produced e-cigarettes that deliver nicotine. But journalists are still drawing a connection to products like Juul, and public health officials are using this vaping scare as an opportunity to warn the public that "e-cigarettes do not emit a harmless aerosol" and "can include a variety of potential[ly] harmful ingredients," as the CDC's Brian King put it during a press briefing last Friday. Although "we haven't specifically linked any of those specific ingredients to the current cases," King said, "we know that e-cigarette aerosol is not harmless."

This is blatant, baseless scaremongering. Because black-market cannabis products may pose unknown hazards, King seems to think, people should stay away from legal nicotine delivery devices, even though they are a much less dangerous alternative to conventional cigarettes. Siegel argues that the CDC's vague, blanket warnings about "e-cigarettes" and "vaping" are "irresponsible and a potential hazard to public health," driven by "a categorical anti-vaping stance that has become commonplace and threatens to undermine decades of anti-smoking efforts."

Yesterday, USA Today reported that the CDC, the FDA, and state health departments "say they are completing the painstaking work of tracing common factors that may have triggered the spate of vaping-related lung illnesses." But given the way these cases were identified, there may be no "common factors."

Doctors noticed that some patients with respiratory problems were vapers, leading to a post hoc, ergo propter hoc presumption that has colored all subsequent judgments about the causes of those symptoms. Public health officials invited reports about people who 1) vaped and 2) had breathing problems. They got a bunch of them, seemingly confirming the initial hypothesis. But some of these cases may have nothing to do with vaping, while those that do may involve a variety of specific agents. In fact, that is almost bound to be the case, since we know the patients used different products, delivering different drugs, purchased in different places.

What does this all have to do with a smoker who is considering a switch to a different source of nicotine that could save his life by eliminating the tobacco combustion products he is currently inhaling? Absolutely nothing. Officials who claim to be interested in promoting public health should stop pretending otherwise.

[This article has been updated with comments from Scott Gottlieb.]