Since the coronavirus pandemic erupted last year, PolitiFact has fact-checked hundreds of misleading statements about the development, deployment, content, safety and effectiveness of COVID-19 vaccines. Even as the U.S. sees a rise in cases among unvaccinated populations, the unsupported claims keep coming.

False narratives that the vaccines are mandatory and that they result in widespread death more than doubled across social media, broadcast and traditional media, and online sites over the past three months, according to Zignal Labs Inc., a media intelligence firm.

“Every adult can get it, so of course every adult is in the potential audience for misinformation,” said John Gregory, deputy health editor at NewsGuard, a firm tracking online misinformation.

Hundreds of anti-vaccine groups remain active on Facebook, and one watchdog group found that 12 online influencers were behind 65% of the anti-vaccine misinformation on Facebook, Instagram and Twitter. False claims are frequently boosted by politicians and pundits, too.

People who get their news from conservative media are more likely to believe misinformation about the vaccines, according to a recent survey from the University of Pennsylvania. On Fox News, for example, recent calls by some hosts to get vaccinated came against the backdrop of months of skepticism and misleading claims from the likes of Tucker Carlson.

Here are 10 persistent falsehoods we have seen, and our related fact checks.

“The COVID-19 vaccines do not work.” FACT: They do.

“Maybe (the COVID-19 vaccine) doesn’t work, and they’re simply not telling you that,” Carlson said in April, citing government advice to continue taking certain precautions. PolitiFact rated that Pants on Fire.

Clinical trials and real-world studies proved the vaccines are safe and effective at protecting against infections and severe symptoms. As vaccinations ramped up in the spring, cases and hospitalizations went down. Public health officials now say 99.5% of COVID-19 deaths in the past few months have been among unvaccinated people. Our fact-checking has found that:

• No, it isn’t safer to “skip” the vaccine.
• Yes, the vaccines are as effective as manufacturers and public health officials have said.
• The vaccines are more protective, not less, than antibodies from a natural infection.
• Dr. Anthony Fauci, the chief medical adviser to President Joe Biden, never said that the vaccines don’t work, as one viral video claimed.

“The COVID-19 vaccines were not properly tested or developed.” FACT: They were.

The U.S. allowed emergency use of three different vaccines after clinical trials involving tens of thousands of participants showed they were safe and effective. But false and misleading claims about the vaccines’ development still circulated, including:

• A blog post that claimed the Food and Drug Administration said Pfizer-BioNTech’s vaccine killed two trial participants. That’s not what happened.
• A local politician’s Pants on Fire claim that the vaccines couldn’t possibly be safe because they were developed so quickly.
• A pair of Instagram posts that claimed vaccine developers skipped animal and human trials, False and False.
• Claims that the FDA never signed off on the vaccines, even though the agency allowed three for emergency use. And, no, it wasn’t Fauci’s wife who gave the green light.
• A False internet rumor that said Moderna developed the vaccine in 2019.
• A post that claimed Fauci invested millions of dollars in the shots. There’s no evidence of that.

“The COVID-19 vaccines are mandatory.” FACT: They aren’t.

Colleges and businesses can require vaccinations as a condition of entrance or employment, despite online posts claiming that’s illegal. Businesses are not barred by health information privacy laws from asking customers about vaccinations, either.

But social media users and influencers have continued to warn without evidence that the White House will be making the vaccines mandatory. The White House has not announced any such plans, and as the federal government has little authority to require vaccinations.

• A federal law Facebook users warned about in 2020 never materialized.
• Biden did not promote mandatory vaccinations in a March address, despite one conservative commentator’s claim in a Facebook Live video.
• A national door-to-door effort to inform unvaccinated Americans of their options does not involve federal employees forcing people to get the shots.

“The COVID-19 vaccines contain microchips for government tracking.” FACT: They don’t.

Baseless claims about COVID-19 vaccines containing microchips were circulating well before the vaccines existed — even though that’s not physically possible.

As Dr. Paul Offit, chair of vaccinology at the University of Pennsylvania’s Perelman School of Medicine, pointed out: “A microchip is about 0.5 inch long. That wouldn’t fit through the end of a needle.” Also:

• Democrats never pushed to introduce microchips into Americans’ bodies as part of any mandatory vaccination campaign. Neither did Biden. Or George Soros. Or Bill Gates.
• The Gates Foundation didn’t spend millions to add microchips to all medical injections.
• Gates didn’t call for digital vaccination records. That widespread quote attributed to him was made up.
• Vaccine recipients are not being monitored via certificates of vaccination or automatically enrolled in a government tracking system.
• The government isn’t using vaccine microchips to track recipients’ movements and locations through 5G cellular networks or other technology.
• Viral videos of people claiming that their bodies are interacting with magnets, Bluetooth devices and animal scanners after getting vaccinated don’t prove what they claim to.

“The COVID-19 vaccines contain metals and other problematic ingredients.” FACT: They don’t.

The makeup of the vaccines available in the U.S is no secret. Ingredient lists for the Pfizer, Moderna and Johnson & Johnson shots can all be found online, courtesy of the FDA.

But conspiratorial claims abound:

• Gates isn’t fighting to keep the ingredients secret. They’re already public.
• The vaccines do not contain aluminum, metals or other materials that a magnet could interact with, despite false claims and videos purporting to show otherwise.
• The vaccines do not contain toxic ingredients that are more dangerous than COVID-19.
• The Oxford-AstraZeneca vaccine allowed in parts of Europe does not contain aborted fetal tissue.
• Moderna’s vaccine does not include an ingredient “for research use only,” and Pfizer’s does not contain graphene oxide, as two Instagram videos claimed.
• There is no plot to kill people with vaccines full of saline, which is used to dilute the Pfizer vaccine before it is injected.

“The COVID-19 vaccines have caused widespread death and disease.” FACT: They haven’t.

The COVID-19 vaccines are known to cause some temporary side effects, such as fatigue. But widespread death and serious disease? Such claims often trace back to an unverified federal database that has become a breeding ground for anti-vaccine misinformation.

Carlson, for example, cited the database to suggest that thousands of people had died from the vaccines. His claim rated False. But similarly problematic claims continue to spread online.

The Centers for Disease Control and Prevention wrote as of July 21 that based on its review of all information for death reports in the database, there remains no “causal link” to the vaccines.

• Gates never said that the vaccine would kill 1 million people.
• The vaccines have not been shown to cause death, autoimmune diseases, prion diseases or neurodegenerative diseases, or sudden infant death syndrome.
• There’s no evidence that the vaccines produce a toxin causing heart problems.
• The death rate for vaccinated people is not higher than for unvaccinated people. And vaccine-related deaths don’t rival COVID-19 deaths.
• There’s no evidence that funeral directors said the only people dying are dying because of the COVID-19 vaccine. Most people dying from COVID-19 are unvaccinated.
• The CDC did not say that the vaccine is sending more young people to the hospital than the coronavirus.

“The COVID-19 vaccines killed or harmed various celebrities.” FACT: They haven’t.

Social media users have tried to link the deaths of celebrities and specific people to the COVID-19 vaccines. Those claims haven’t panned out.

• Rapper DMX died of a heart attack, not the vaccine.
• Baseball legend Hank Aaron died from natural causes, not the vaccine.
• Boxer Marvelous Marvin Hagler died from natural causes, not the vaccine.
• Social media claims that four British Airways pilots, five JetBlue crew members, and an Ohio doctor died from the vaccines are False. A video of a nurse becoming dizzy after her shot lacked context and was not indicative of something dangerous in the vaccine.
• Danish soccer player Christian Eriksen’s on-field collapse in June was not due to the vaccine. His professional club said he hadn’t received a shot.

“The COVID-19 vaccines alter your DNA.” FACT: They don’t.

The COVID-19 vaccines don’t alter people’s DNA.

The available vaccines use different technologies to instruct cells to build protection against the virus. But no genetic material enters the part of the cell that hosts DNA, per the CDC. 

Gates didn’t say that the vaccines would alter DNA, nor did Moderna’s chief medical officer.

And the shots definitely don’t replace DNA with genetic coding that makes people “cooperate with the New World Order,” as one Pants on Fire Instagram post claimed.

“The COVID-19 vaccines stunt fertility and disrupt pregnancies.” FACT: They don’t.

Online rumors linking the vaccines to pregnancy and fertility complications are unsupported. Studies are ongoing, and the CDC says on its website:

“There is currently no evidence that COVID-19 vaccination causes any problems with pregnancy, including the development of the placenta. In addition, there is no evidence that female or male fertility problems are a side effect of any vaccine.”

Some false claims about fertility are premised on the idea that a spike protein generated after vaccination resembles a protein on placental cells. But the two proteins aren’t similar enough to confuse the immune system into attacking the placental cells, PolitiFact reported.

• Public health officials have not cautioned against getting pregnant after vaccination.
• The vaccines did not cause a 366% increase in United Kingdom miscarriages over six weeks in March.
• There is no evidence that the vaccines caused hundreds of miscarriages, and an online rumor about an “82% miscarriage rate” misrepresented a study’s preliminary data.
• A study did not show that the vaccine affects sperm production.

“The COVID-19 vaccines can ‘shed’ to affect unvaccinated people.” FACT: They don’t.

The vaccines do not “shed” to affect unvaccinated people. In fact, that’s biologically impossible.

Such shedding can only occur with vaccines that use weakened forms of the virus, according to the CDC. But none of the COVID-19 shots are live-virus vaccines.

• A vaccinated person won’t affect unvaccinated people’s menstrual cycles or fertility.
• A vaccinated person won’t cause death and disease in unvaccinated people nearby.
• A vaccinated person won’t pass natural immunity off to unvaccinated people nearby.

This article was originally published by PolitiFact, which is part of the Poynter Institute. It is republished here with permission. See the sources for these fact checks here and more of their fact checks here.