To be clear, the history of vaccines has not been without genuine danger and controversy. In the United States, vaccine opponents received sobering confirmation of their fears in 1901, when thirteen children in St. Louis died after receiving a diphtheria antitoxin that had been accidentally contaminated with tetanus. The same year, a contaminated smallpox vaccine killed several children in Camden, New Jersey. Those tragic incidents led Congress to pass the Biologics Control Act, which standardized the vaccination production process and required pharmaceutical firms manufacturing vaccines to be licensed.

That made vaccine formulation significantly safer but did not eradicate resistance to it. In his book, Suspicious Minds, Rob Brotherton points to a controversy during the mid-1970s, when parents in England, Asia, and the United States claimed that the DPT vaccine (against diphtheria, pertussis, and tetanus) had made their children sick. It is likely that the vaccine did cause seizures and development delays in some children; like all vaccines, DPT carried a risk of side effects. In 1982 a documentary called Vaccine Roulette aired on a Washington, DC, station: it gives equal time to vaccine researchers working for the FDA and to researchers calling the DPT vaccine outdated and insufficiently “pure.” It downplays the dangers of serious diseases like whooping cough while presenting the vaccines as irresponsible to give to children. In both the United Kingdom and the United States, vaccination rates dipped in response to the film; as in the case of MMR, they began to increase only after concerted responses from the American Academy of Pediatrics and the CDC, and the British Joint Commission on Vaccination and Immunization.

In 1986, the United States passed the National Childhood Vaccine Injury Act and in 1988 created the National Vaccine Injury Compensation Program, whose very existence has been used as proof by anti-vaccination activists that vaccines are unavoidably unsafe. In fact, though, the program, which is funded through the Department of Health and Human Services, was set up as a response to a wave of DPT-related lawsuits. Parents alleging DPT injuries were awarded huge amounts at jury trials, and soon pharmaceutical companies were no longer producing the DPT vaccine, fearful of litigation. When the last DPT vaccine manufacturer threatened to stop production, the vaccine court was created as a no-fault system for the federal government to award money to the plaintiffs without affecting pharmaceutical companies or burying vaccinations under a tide of lawsuits.

The CDC now uses a tool called the Vaccine Adverse Event Reporting System, which requires doctors to report reactions to vaccinations. The CDC estimates that doctors file about thirty thousand reports each year, about 85 to 90 percent of them describing mild side effects like fever, arm soreness, or “crying and mild irritability.” The remaining 10 to 15 percent involve serious adverse events resulting in “permanent disability, hospitalization, life-threatening illness, or death.” Even then, the CDC and most public health experts agree that while vaccines can be followed by adverse reactions, they are rarely caused by the vaccine. Nonetheless, there are still vaccine deaths across the world: in June 2017 in South Sudan, fifteen children died after a botched measles vaccination. The vaccine was apparently left unrefrigerated, and one syringe was reused for four days.

For their part, anti-vaxxers tend to downplay the seriousness of disease outbreaks when they do occur. A popular anti-vaccination naturopathic physician, Sherri Tenpenny, has for years claimed that infants “rarely” die from measles. “Why is there such HYSTERIA over measles?” Tenpenny wrote on her medical practice’s Facebook page in 2013. “It is a rash, fever and desquamation of skin on hands and soles after 10 days, signaling the end of the infection and the resultant lifetime immunity. Doctors in the 1940s (the last THINKING doctors, IMO) wrote many articles about how important a measles infection was to long term health and vitality. Now, we act like measles somehow equates to DEATH.”

In fact, it can. According to the World Health Organization, some 134,000 children worldwide died from measles in 2015. Early that year, a measles outbreak at Disneyland infected 147 people and spread across seven states and into Canada and Mexico. It was the largest outbreak of the disease since 1991, and an analysis in the journal JAMA Pediatrics found that it was fueled in part by parents who declined to vaccinate their kids.

The need for everyone to vaccinate their children—except those with legitimate medical reasons—was brutally demonstrated when a sudden measles outbreak in Minnesota revealed that Somali parents there weren’t vaccinating their children. Vaccination rates in the area first started to dip in 2008, when Somali parents there noticed, with alarm, that many of their children were enrolled in programs for children on the autism spectrum. They didn’t recall having seen autism before coming to the United States. Even though a University of Minnesota study showed that autism rates were virtually the same among white and Somali children, and only somewhat higher than the Latino and African American populations, the findings didn’t soothe frightened parents. Oh, and also—between 2008 and 2016, Andrew Wakefield came to speak at Somali community forums at least twice.

In 2016, public health officials found that only about 41 percent of Somali toddlers in Minnesota had received the MMR vaccine, according to the state Department of Health, with many parents in the community apparently following anti-vaccine activists’ instructions to either forgo the vaccine entirely or wait till their children were five years old. (The CDC recommends that children get their first dose at twelve to fifteen months old.) The outbreak began in late March 2017; by August, seventy-nine people had become sick and twenty-two were hospitalized. More than eight thousand people in all were estimated to have been exposed to the disease.

In both the cases of Disneyland and Minnesota, anti-vaccination activists attributed the outbreaks to dark machinations. They suggested that at Disneyland the outbreak was either engineered by the government or played up by a compliant media to pass a controversial California state law, SB 277, which requires immunizations for children to attend daycare or public school. Conservative television personality and enthusiastic conspiracist Glenn Beck baldly called the outbreak a “hoax.” “Is it possible we have been lied to about the measles, this outbreak?” he pontificated on his show in February 2015. The news reports, he said, were meant to instill a “herd mentality,” so that parents would “grab their children and obey the government.”

In Minneapolis, health officials told the Washington Post they had received word that white women visiting Somali communities across the city had claimed, the Post wrote, that “the measles outbreak had been created by the Health Department to persuade Somali parents to vaccinate.” The women were never identified. Wakefield, meanwhile, told the Post he’d visited the Somali community there only after they became concerned about autism among their children. “The Somalis had decided themselves that they were particularly concerned,” he told the paper. “I was responding to that.”

As for the outbreak, he added, “I don’t feel responsible at all.”

The argument that the government uses medicine to instill cowlike compliance extends well beyond vaccines. For years, Americans have been terrified of fluoride, which some cities started adding to their water supply in 1945. Conspiracies and Secret Societies, a conspiracy-leaning encyclopedia, sums up the most common objection to the practice: the Nazis did it first. “Drinking water containing fluoride was first utilized in Nazi prison camps,” the authors, Brad and Sherry Steiger, write. (The couple also cowrote a number of books about UFOs, werewolves, and the paranormal.) “In the 1930s Hitler and Nazi scientists envisioned world dominion through mass medication of water supplies. A report submitted to the German general staff indicated findings that repeated doses of very small amounts of fluoride would gradually decrease people’s ability to resist domination, slowly narcotizing a certain region of the brain and rendering the individuals submissive to the will of those who wished to govern them.”

That’s all very specific (apart from “a certain region of the brain”), but Holocaust historians say there’s no evidence whatsoever that the claim is true. Patricia Heberer, who specializes in German medical history, including the hideous Nazi experiments, told PolitiFact, “I just can’t see it.” But, Heberer added, she’d heard similar claims during the Cold War about Communists dumping fluoride in the water to narcotize the populace. The American Dental Association—which, as you’d expect, is sturdily pro-fluoride—points out that historical objections to fluoride tend to shift with the times.

“In the 1950s fluoridation was a Communist plot,” according to a surprisingly readable ADA pamphlet on the subject. “With America’s growing concern for environmental issues in the 1960s, fluoridation was pollution. After the Vietnam War in the 1970s, the anti-fluoridationists capitalized on the popularity of conspiracy theories by portraying fluoridation as a conspiracy between the U.S. government, the dental-medical establishment and industry. As Americans became more concerned about their health in the 1980s, anti-fluoridationists claimed fluoridation caused AIDS and Alzheimer’s disease. In the 1990s, claims of fluoride causing hip fractures and cancer were designed to resonate with aging baby boomers. With the new millennium, overexposure and toxicity, in association with lead and arsenic poisoning, have surfaced as common themes.”

Underlying these changing concerns is one constant: fear of the heavy, strangling hand of government control. Mandatory vaccine laws and such measures as putting fluoride in the water are unquestionably good for public health, but they tend to create a noticeable backfire effect, confirming people’s beliefs in an overbearing government. Just to complicate things, it is also true that the government has engaged in very real, disturbing medical experimentation on civilians and then covered it up. That includes the widely forgotten yet deeply troubling program of federally funded scientists irradiating thousands of people.

Beginning in 1944 and continuing for the next three decades, in secretive federally backed experiments, thousands of prisoners, terminally ill patients, and disabled children were dosed with radiation, usually derived from plutonium, to test the effects of radioactive contamination. The breadth and cruelty of the program beggar belief: in the late 1940s and early 1950s, a group of children at the Walter Fernald State School in Massachusetts were given both radioactive iron and calcium in their milk and oatmeal, an experiment engineered by the Massachusetts Institute of Technology in partnership with Quaker Oats, who wanted to use radioactive material to prove that the nutrients in its oatmeal “traveled throughout the body,” according to the New York Times.

In a letter to their parents, the school’s superintendent, Malcolm J. Farrell, said the children would be given a “special diet” in order to study the way the body absorbed iron and vitamins. He did not ask for consent to irradiate their children; instead, the boys involved thought they’d been invited to join a special “science club.”

The radiation doses were fairly low and none of the former Fernald students—wards of the state who were often inaccurately classified as mentally disabled—are reported to have suffered any significant health effects. But the experiment was still appalling: the boys were talked into participating without any idea what they were ingesting, and it’s doubtful they could have refused: until the 1960s, Fernald was known as a brutal place, with meager food and filthy living conditions. One former ward, Fred Boyce, called it “a prison,” and told news outlets he was outraged and disgusted when he later learned he’d been one of the children fed radioactive material. In 1996, Boyce organized a class-action lawsuit with about thirty other former Fernald wards, eventually winning a $1.85 million settlement from MIT and Quaker Oats.

In the mid-1960s through the 1970s, prisoners in the states of Oregon and Washington had their testicles irradiated through a project directly funded by the Atomic Energy Commission, part of a study to determine how much radiation astronauts could be exposed to during missions. Participation in the program was supposedly voluntary—as voluntary as anything can be for a prison inmate—but many of the men who participated later said they had not been told of the long-term risks involved. Some told the Washington Post decades after that they suffered from rashes, lumps, and irritation on their testicles; one said his testicle became fused to his scrotum after the experiments.

Some cases were so bizarre that survivors were taken to be insane when they discussed them. Such was the sad story of Elmer Allen, an African American train porter who lived in the tiny town of Italy, Texas. He had been diagnosed with bone cancer in his left leg in 1947, and, according to his family, was asked by doctors “whether they could inject him with a radioactive trace element.” Allen’s leg was injected, but the procedure didn’t save it; the leg was amputated and taken by researchers at the University of San Francisco, where he was being treated.

In 1973, Elmer and his wife were offered a free trip to New York, told that doctors there wanted to follow up on the success of the 1947 operation two decades later. But as Fredna and Elmer were on their way to New York, they were pulled off the train in Chicago and taken by limousine to the Argonne National Laboratory. Scientists wanted to run tests to see the effect of the radioactive trace on Elmer’s body in the intervening decades. In the process, they found damage in his jawbone that looked like it had been caused by radiation.

In the course of his life, Elmer reportedly struggled with alcoholism and been diagnosed as a paranoid schizophrenic. He would tell his neighbors that he’d been used as a “guinea pig” by the government, but they and, for a time, his family, took that to be the ramblings of a disturbed man.

The mystery was finally solved after Elmer died in 1991, when a reporter, Eileen Welsome, found his name along with those of seventeen other people who had also been injected by government scientists at around the same time at hospitals across the country. The injection turned out to be plutonium, and it had no medical benefit: it was part of the Manhattan Project, the federal research into developing nuclear weapons. The people injected with plutonium were all expected to die soon after receiving the plutonium; scientists were using them to test the body’s reaction to exposure to radioactive material.

“The tragic part about Elmer’s story,” Welsome told Amy Goodman on Democracy Now! in 2004, “is that nobody believed him.”

Experiments were even carried out on the dead, with bodies being exhumed to test their radiation levels. In those cases, too, families frequently weren’t given enough information about what they were being asked to consent to. In one project in the mid-’50s, Project SUNSHINE, the cadavers of dead infants were exhumed from across Australia and Europe and sent to the United States to test whether a particular radioactive isotope was concentrated in their bones. Their next of kin were not informed.

In a particularly ghoulish detail, Willard Libby, a University of Chicago researcher who worked for the Atomic Energy Commission, was quoted in a commission transcript jovially expressing his search for the bodies of dead babies. “I don’t know how to get them,” Libby said, “but I do say that it is a matter of prime importance to get them and particularly in the young age group. So, human samples are of prime importance, and if anybody knows how to do a good job of body snatching, they will really be serving their country.”

In all, about four thousand radiation experiments took place during those three decades, according to an advisory committee created in 1994 by Bill Clinton to examine their grim history. Only a handful of victims or their survivors ever got compensation from the government.

Then there is MKUltra, the series of mind-control experiments conducted by the CIA that would challenge the imagination of the most paranoid of conspiracy theorists. Founded in 1947, the CIA was concerned that the Communists had discovered a mind-control drug, which spurred the agency’s efforts to get America into the race. MKUltra was approved in 1953, with a then-enormous budget of $300,000 and a specific mandate to test the efficacy of LSD. Presiding over MKUltra—the umbrella name for one hundred forty-nine bizarre projects designed to test what mind-altering drugs could do for national defense—was Sidney Gottlieb, a chemist and former chief of the CIA’s technical services division. (Gottlieb, a very busy man, was also involved in the CIA’s “gadget shop,” which produced devices aimed at killing Fidel Castro and other inconvenient world leaders.) MKUltra experiments involved testing the drugs on human subjects; in some experiments, the subjects were unaware that they were being drugged. In MKUltra’s first year of operation, an FBI agent named Frank Olson, covertly dosed with LSD, died. The LSD had been mixed in a bottle of Cointreau and offered to the unwitting Olson by Gottlieb; after drinking it, Olson suffered a mental break and, nine days later, threw himself from a tenth-story window. But nothing seemed to slow the program’s bizarre work for long; even then, MKUltra was only halted temporarily.

Some of the MKUltra experiments straddled the line between science and sadism. In one, the agency set up a controlled safe house, where sex workers were instructed to dose their clients, who were then observed from behind two-way mirrors. The project was dubbed Operation Midnight Climax, which makes it sound as if everyone involved in creating it was having a good time. CIA operatives soon leaped beyond the bounds of the safe house: people were dosed with LSD, marijuana, and other drugs in restaurants and bars and on the beach. A CIA source speaking to author John Marks told him, “If we were scared enough of a drug not to try it out on ourselves, we sent it to San Francisco.”

Most of the MKUltra records were deliberately destroyed by the government in 1973. According to a contemporaneous report in the New York Times, that was done to hide evidence of possible criminal wrongdoing, including Sidney Gottlieb’s personal involvement in the death of Frank Olson. The project only came to public attention in 1975, as a result of two government actions: the Church Committee—a Senate Select Committee assigned to look into spying by the CIA, NSA, and FBI on both foreign leaders and US citizens, which found widespread examples of harassment of political activists, including Martin Luther King, Jr.—and the President’s Commission on CIA Activities in the United States, commissioned by Gerald Ford. (Even then, it took investigative stories by Seymour Hersh at the New York Times and other journalists to expose the worst of the outrages, as well as the destruction of records.) The CIA called MKUltra a shameful chapter in its history, never to be repeated, but its shadow was not easily dispelled. Concerns about government mind control are so entrenched as to be the subject of jokes; the original idea of a tinfoil hat, after all, is to keep the government from beaming its rays of influence into one’s brain.

Gottlieb, meanwhile, never faced any consequences for his work with the CIA—why would he?—and upon retiring, moved to India for eighteen months with his wife to run a leper colony, according to a New York Times obituary. From there, he bought a cabin in Virginia, tried unsuccessfully to start a commune, and focused his time on folk dancing and herding goats along with, as the Times put it dryly, “consciousness-raising and fighting lawsuits from survivors of his secret tests.” He died at eighty. Secretive to the last, his wife declined to disclose his cause of death.