Any plot that relies on my ability to maintain conspiratorial silence is doomed to fail. Whatever skills it takes to succeed in espionage or racketeering, I patently lack.

Just a couple of days ago, in a slip I knew I’d make sooner or later, I signed an email from my pen name’s account with my real moniker. (As noted in my bio, I write with a pseudonym.) The worst that came of it was slight confusion on the recipient’s part and a small compromise in the security of an identity I maintain out of convenience more than necessity. Were I actually part of some massive conspiracy of silence with higher stakes, I probably would have been rubbed out by professional goons by now.

And yet, according to the theories of at least one member of Congress, several celebrities, and nearly half of the American people, I am a small part of one or more nefarious schemes to poison or sicken innocent people. To believe, for example, that vaccines are actually harmful is to believe that pretty much every health care provider in this country is not only secretly malevolent, but also really good at maintaining airtight adherence to omertà over a period of several decades. Put bluntly, Alicia Silverstone and Jenny McCarthy think I’m knowingly poisoning kids, and mum’s the word.

But the aptly-cast star of “Clueless” is hardly alone. According to a study reported in the journal JAMA Medicine recently, 49 percent of Americans believe in at least one of six medical conspiracies.

The authors surveyed 1,351 adults and asked if they believed any of the following: that the FDA was hiding natural cancer cures; that cellphones actually cause cancer; that the CIA spread HIV to African Americans on purpose; that genetically-modified foods were part of a worldwide population-control effort; that doctors administer vaccines knowing that they are harmful; or that water fluoridation is a plot to get rid of industrial waste. Nearly half believed at least one of those theories, the most popular being the one about natural cancer cures at 37 percent, with the one about cellphones and the one about vaccines tied for second at 20 percent. Three or more conspiracies were believed by 18 percent. As a big proponent of both comprehensive vaccination for children and water fluoridation, that implicates me in two of them.

Every one of those theories seems like the kind of googly-eyed lunacy only the fringiest fringe-dwellers would believe. But it’s hard to dismiss 49 percent of survey respondents as occupying some kind of fringe. No less a personage than Rep. Dana Rohrabacher, GOP congressman from California’s 48th district and the vice chairman of the House Committee on Science, Space and Technology, is quoted by an anti-fluoridation website saying, “I don’t know whether or not fluoridating the water helps people’s teeth become better or not.”

Leaving aside the startling implications of a member of the House Science Committee not having a rudimentary understanding of science, I can only imagine what motivation Rep. Rohrabacher would ascribe to the American Dental Association for supporting a practice that, in fact, costs them business by preventing cavities and lowering the need for expensive dental procedures.

Unsurprisingly, the study showed that the more one subscribes to medical conspiracy theories, the less likely one is to trust doctors or the medical establishment. But we don’t have the luxury of simply writing these people off and attending to those who view us with less suspicion. When a large segment of the population holds on to one or more erroneous medical beliefs, their resultant decisions have implications for everyone. Anti-vaxxers failing to vaccinate their kids is having a catastrophic effect on the herd immunity everyone relies on to keep preventable illness at bay. Efforts to block fluoridation leave everyone’s children more susceptible to dental decay, the most common chronic disease of childhood and a cause of needless pain, psychological distress, and even school failure (it’s hard to concentrate when your teeth hurt all day).

But of course, I can cite statistics until I’m blue in the face. For people prone to believe doctors like me are part of some malign conspiracy, nothing I say will make a difference. The best I can hope for is that a steady drumbeat of factually sound information will remain part of our public narrative, bit by bit eroding the mass of misinformation and outright paranoia we’re facing.