From spring break parties to Mardi Gras, many recall the last major “normal” event they attended before the dawn of the Covid-19 pandemic, prompting governments worldwide to implement stay-at-home advisories and shutdowns.

Even prior to the detection of the first Covid-19 case in the U.S., fears and uncertainties fueled the rapid spread of misinformation. In March 2020, schools shuttered, remote work became the norm, and grocery stores enforced physical distancing. However, misinformation continued to thrive, inundating fact-checkers and public health officials. False claims linked Covid symptoms to 5G wireless technology, while unverified treatments flooded social media and political discourse. Amid ambiguity about the virus’s origins, some denied its existence altogether, leading PolitiFact to dub “downplay and denial” its 2020 “Lie of the Year.”

Four years on, public health measures have largely eased, but Covid misinformation persists, primarily revolving around vaccines and related conspiracy theories. PolitiFact has conducted over 2,000 fact checks on Covid vaccines alone.

According to Tara Kirk Sell, a senior scholar at the Johns Hopkins Center for Health Security, there has been a shift in levels of trust among misinformation researchers. Early in the pandemic, denial and fake cures prevailed, while later misinformation focused more on vaccines, often taking on a partisan nature.

A Loss of Trust in the Vaccines

One prevailing Covid misinformation narrative is a loss of trust in vaccines. Despite rapid development, with the first U.S. vaccinations administered in December 2020, skepticism persists. Experts attribute the swift vaccine development to saving millions of lives and preventing hospitalizations. Data from the Centers for Disease Control and Prevention shows a significant decline in Covid-related deaths since vaccines were introduced.

However, misinformation regarding the efficacy and safety of Covid vaccines remains prevalent on social media and in the statements of some public officials. U.S. presidential candidate Robert F. Kennedy Jr. has based his 2024 campaign on promoting conspiracy theories about vaccines, earning PolitiFact’s designation as the “Lie of the Year” in 2023.

PolitiFact has debunked various claims, such as the notion that spike proteins from vaccines replace sperm in vaccinated males (false) and the assertion that vaccines can alter DNA (misleading and unsupported by evidence). Social media posts even mocked Kansas City Chiefs tight end Travis Kelce for advocating vaccination, spreading false rumors that the vaccine shuts off recipients’ hearts (untrue). Some individuals cited an American Red Cross blood donation questionnaire as evidence of vaccine unsafety (rated False by PolitiFact).

Experts warn that this misinformation has tangible consequences. A September 2023 survey by KFF found that 57% of Americans express confidence in Covid vaccines, with vaccine skepticism more prevalent among politically conservative individuals. Immunization rates for routine vaccines for other diseases have also decreased, leading to measles outbreaks in states like Florida, Maryland, and Ohio. Florida’s surgeon general has expressed skepticism about vaccines and disregarded CDC guidance on disease containment.

Kindergarten vaccination rates have declined from 95% in the 2019-20 school year to 93% in 2022-23, below the CDC’s recommended 95% target to prevent disease outbreaks. Additionally, exemptions have risen to 3%, the highest recorded rate in the U.S. according to the CDC.

Unsubstantiated Claims That Vaccines Cause Deaths or Other Illness

PolitiFact has encountered numerous baseless claims suggesting that Covid vaccines have caused widespread deaths.

A recent viral post falsely asserted that 17 million people had died due to the vaccine, contradicting evidence from multiple reputable sources such as the World Health Organization and CDC affirming the safety and efficacy of vaccines in preventing severe illness and death.

Another online rumor falsely alleged that the booster vaccine contained eight strains of HIV and would result in a 23% mortality rate. However, vaccine manufacturers’ ingredient lists do not include HIV, and individuals living with HIV were prioritized during the early vaccine rollout to protect them from severe illness.

Additionally, Covid vaccines have been wrongly accused of causing Alzheimer’s and cancer, despite experts finding no evidence to support such claims.

Paul Offit, director of the Vaccine Education Center at the Children’s Hospital of Philadelphia, noted the remarkable scientific achievement of vaccine development juxtaposed with significant public rejection of the technology.

Despite vaccines being available for over three years, approximately 70% of Americans have completed a primary series of Covid vaccination, according to CDC data, with about 17% receiving the most recent bivalent booster.

False assertions often misuse data from the Vaccine Adverse Event Reporting System, a CDC and FDA-run database intended for researchers to identify patterns for further investigation.

An October 2023 survey by the Annenberg Public Policy Center at the University of Pennsylvania revealed that 63% of Americans believe it is safer to receive the Covid-19 vaccine than to contract the disease, down from 75% in April 2021.

Furthermore, celebrities like Betty White, Bob Saget, Matthew Perry, and DMX have been falsely linked to vaccine-related deaths, perpetuating misinformation. Céline Gounder, an infectious disease specialist, attributes these claims to cognitive bias and motivated reasoning, emphasizing the need to combat falsehoods with truth, particularly in personal tragedies like her husband’s passing, which anti-vaccine advocates inaccurately attributed to the Covid vaccine.