A variety of unfounded conspiracy theories and other misinformation about COVID-19 vaccines have spread based on misunderstood or misrepresented science, religion, and law. These have included exaggerated claims about side effects, misrepresentations about how the immune system works and when and how COVID-19 vaccines are made, a story about COVID-19 being spread by 5G, and other false or distorted information. This misinformation, some created by anti-vaccination activists, has proliferated and may have made many people averse to vaccination.

Vaccine hesitancy has led to governments and private organizations around the world introducing measures to incentivize or coerce vaccination, such as lotteries, mandates, and free entry to events, which has in turn led to further misinformation about the legality and effect of these measures themselves. Critics of vaccine mandates have argued that such requirements infringe on individual medical choice and personal autonomy.

In the US, some prominent biomedical scientists who publicly advocate vaccination have been attacked and threatened in emails and on social media by anti-vaccination activists.

Misinformation

Various false theories have spread in different parts of the world regarding the COVID-19 vaccines.

COVID-19 and variant related claims Prevalent COVID-19 skepticism Prior to the vaccine launch many citizens expressed skepticism that COVID-19 was a serious disease or that their countries had cases or high number of cases of the disease during 2020 and 2021. This prior skepticism that was pushed by the late President of Tanzania, John Pombe Magufuli is seen as a leading reason for vaccine hesitancy within the country. Magufuli declared Tanzania COVID-19 free in mid-2020 and pushed herbal remedies, praying and steam inhalation as remedies to COVID-19.

Delta variant and vaccines As the delta variant of COVID-19 began to spread globally, disinformation campaigns seized on the idea that COVID-19 vaccines had caused the delta variant, despite the fact that the vaccines cannot replicate the virus. A French virologist likewise falsely claimed that antibodies from vaccines had created and strengthened COVID-19 variants through a previously debunked theory of Antibody-dependent enhancement. A related debunked theory, out of India, claimed that COVID-19 vaccines were lowering people's ability to withstand new variants instead of boosting immunity.

The website Natural News published an article in July 2021 claiming that CDC director Rochelle Walensky admitted that COVID-19 vaccines do not protect against the delta variant and that vaccinated people could be superspreaders due to having a higher viral load. Walensky actually said in a press briefing that vaccinated and unvaccinated people could have "similarly high" viral loads when infected with the delta variant, but did not say that vaccinated people had a higher viral loads or were "super-spreaders". She also stated that the vaccine "continues to prevent severe illness, hospitalization, and death", even against the delta variant. A July 2021 study in the New England Journal of Medicine reported that the Pfizer–BioNTech COVID-19 vaccine was 88 percent effective in preventing symptomatic infections caused by the delta variant.

Organized crime Fake vaccines In July 2021, Indian police arrested 14 people for administering doses of fake salt water vaccines instead of the Oxford–AstraZeneca COVID-19 vaccine at nearly a dozen private vaccination sites in Mumbai. The organizers, including medical professionals, charged between $10 and $17 for each dose, and more than 2,600 people paid to receive the vaccine.

Interpol issued a global alert in December 2020 to law enforcement agencies in its member countries to be on the lookout for organized crime networks targeting COVID-19 vaccines, physically and online. The WHO also released a warning in March 2021 after many ministries of health and regulatory agencies received suspicious offers to supply vaccines. They also noted that some doses of the vaccines were being offered on the dark web priced between $500 and $750, but there was no way to verify the distribution pipeline.

Fake vaccination cards In the United States, there was a surge of individuals either looking to purchase fake vaccination cards, alter medical records to show vaccination, or create fake vaccination cards to sell. In Hawaii a vacationer was arrested after it was discovered she had a fake vaccination card, a California doctor was arrested for falsifying patients' vaccination records, and three state troopers in Vermont were arrested for helping create false cards. In August 2021 US Customs and Border Prevention agents seized 121 packages with more than 3,000 fake vaccination cards that had been shipped from Shenzhen to be distributed in the US.

Check Point research released in August 2021 showed that fake vaccination cards were being sold via messaging apps and priced between $100 and $120 a card. Interpol announced that they were seeing a direct correlation between countries requiring negative COVID-19 tests to enter the country and the increased number of provided fake vaccination cards.

Medical claims

Claims of inefficacy

Recurrent claims, based on misinterpretation of statistical data, have been made regarding the efficacy of COVID-19 vaccines. A frequent fallacy consisted in concluding on the ineffectiveness (or low effectiveness) of vaccines after noticing the apparently high proportion of vaccinated patients among COVID-19-related hospitalisations and deaths, without taking into account the high proportion of vaccinated people among the general population, thus committing the base rate fallacy; or without taking into account the tendency of people at higher risk of developing severe illness from COVID-19 to be vaccinated in priority, thus ignoring the Yule–Simpson effect.

In the United Kingdom, a report from the Scientific Pandemic Influenza Group on Modelling (SPI-M), published in March 2021, predicted that 60% of hospitalisations and 70% of deaths would be among people who had received two doses of the vaccine, despite the latter remaining highly effective. The report stated: "This (modelling) is not the result of vaccines being ineffective, merely uptake being so high".

Multiple studies have confirmed the effectiveness of a booster dose given on top of the two normal doses of the Pfizer–BioNTech COVID-19 vaccine. There is evidence that those who have received a boosted dose experience reduced severity of infection, in addition to reduced likelihood of developing COVID-19 to begin with.

On 17 January 2023, Ron DeSantis claimed, "Almost every study now has said with these new boosters, you're more likely to get infected with the bivalent booster," but PolitiFact rated that claim False, noting that, on the contrary, a "study found that the bivalent booster is 30% effective in preventing infection from the virus."

mRNA vaccines are not vaccines Financial analyst and self-help entrepreneur David Martin claimed that mRNA vaccines do not fit the U.S. Centers for Disease Control and Prevention's (CDC) or the U.S. Food and Drug Administration's (FDA) definitions of a vaccine because they do not prevent transmission of SARS-CoV-2, the virus that causes COVID-19. While research has been ongoing to evaluate the effect of vaccination on SARS-CoV 2 transmission, neither the CDC nor the FDA stipulate that vaccines must stop transmission of a virus, both stating that a vaccine is a product that stimulates the immune system to produce immunity to an infectious agent.

Altering human DNA The use of mRNA-based vaccines for COVID-19 has been the basis of misinformation circulated in social media, wrongly claiming that the use of RNA somehow alters a person's DNA. The DNA alteration conspiracy theory was cited by a Wisconsin hospital pharmacist who deliberately removed 57 vaccine vials from cold storage in December 2020 and was subsequently charged with felony reckless endangerment and criminal damage to property by Ozaukee County prosecutors.

mRNA in the cytosol is very rapidly degraded before it would have time to gain entry into the cell nucleus (mRNA vaccines must be stored at very low temperature to prevent mRNA degradation). Retrovirus can be single-stranded RNA (just as SARS-CoV-2 vaccine is single-stranded RNA) which enters the cell nucleus and uses reverse transcriptase to make DNA from the RNA in the cell nucleus. A retrovirus has mechanisms to be imported into the nucleus, but other mRNA lack these mechanisms. Once inside the nucleus, creation of DNA from RNA cannot occur without a primer, which accompanies a retrovirus, but which would not exist for other mRNA if placed in the nucleus. Thus, mRNA vaccines cannot alter DNA because they cannot enter the nucleus, and because they have no primer to activate reverse transcriptase.

Because of misinformation suggesting that COVID-19 might alter DNA, some academics insisted that mRNA vaccines were not a "gene therapy" to prevent the spread of this misinformation, but others said that mRNA vaccines were a gene therapy because they introduce genetic material into cells.

Reproductive health In a December 2020 petition to the European Medicines Agency, German physician Wolfgang Wodarg and British researcher Michael Yeadon suggested, without evidence, that mRNA vaccines could cause infertility in women by targeting the syncytin-1 protein necessary for placenta formation. Their petition to halt vaccine trials soon began circulating on social media. A survey of young women in the United Kingdom later found that more than a quarter would refuse COVID-19 vaccines out of concerns for their effects on fertility. A study in Andrologia found that Google searches relating to a supposed link between vaccination against COVID-19 and adverse effects on fertility increased following the Emergency Use Authorization of COVID vaccines in the United States, indicating that concerns about alleged impacts on fertility are a major contributor to vaccine hesitancy. Syncytin-1 and the SARS-CoV-2 spike protein targeted by the vaccines are largely dissimilar, sharing a sequence of only four amino acids out of several hundred. A study conducted on 44 rats injected with the Pfizer–BioNTech COVID-19 vaccine at doses over 300 times the human dose by body weight and 44 rats injected with placebo found no statistically significant evidence of any adverse effects on the fertility of female rats or on the health of the offspring of rats (the 3% lower pregnancy rate found in the vaccine group was not statistically significant). David Gorski wrote on Science-Based Medicine that Wodarg and Yeadon were "stoking real fear [...] based on speculative nonsense".

False claims that a vaccinated person could "shed" SARS-CoV-2 spike proteins, allegedly causing menstrual irregularities or other harmful effects on the reproductive health of non-vaccinated women who are in proximity to them, such as miscarriage, were cited by the Centner Academy, a private school in Miami, which announced it would not employ teachers who received the COVID-19 vaccine. Other businesses refused to serve vaccinated customers, citing concerns that vaccinated people could shed the virus. Some promoters of this claim have recommended the use of face masks and social distancing to protect themselves from those who have been vaccinated. Gynecologist and medical columnist Jen Gunter stated none of the vaccines currently approved in the United States "can possibly affect a person who has not been vaccinated, and this includes their menstruation, fertility, and pregnancy".

Risk of diseases

Bell's palsy