Myths persist about pediatric COVID-19 vaccines and myocarditis

This week, popular social media posts attacked maternal immunizations and a potential ovarian cancer vaccine. Regionally, social media users debated vaccines for older adults and vaccine mandates.

Old myths about COVID-19 vaccine safety recirculated online this week as vaccine opponents targeted vaccines for older and pregnant adults. A preprint study was used to falsely claim that only mRNA COVID-19 vaccination—and not COVID-19 infection—is linked to myocarditis. Meanwhile, popular social media posts falsely warned that any vaccination during pregnancy is unsafe and claimed without evidence that a prospective ovarian cancer vaccine will be unsafe.     

Regional conversations focused on vaccines for adults and school and employer vaccine mandates.  

---

What’s trending nationally in vaccine conversation:

Vaccine opponents have resurfaced the false claim that heart inflammation (also known as myocarditis) in children and adolescents only occurs after mRNA vaccination and not COVID-19 infection. The claim is based on misrepresentations of a preprint Oxford University study that examined outcomes after Pfizer COVID-19 vaccination in the U.K. The misleading narrative about the study and the misrepresentations of its conclusions have been circulating online for several months despite the fact that it has not yet been peer-reviewed. 

The Slovakian government appointed a well-known vaccine opponent to a commission investigating the country’s pandemic response. The commissioner, who previously referred to the COVID-19 pandemic as bioterrorism and fervently opposed Slovakia’s vaccination campaign, released a controversial report in early October that reportedly claims that mRNA COVID-19 vaccines alter DNA and called to ban the vaccines. Notably, the report appears to repeat some of the false claims about COVID-19 vaccine safety promoted by the Florida surgeon general. U.S.-based vaccine opponents are sharing news about the report and are celebrating it as a reckoning. The report has been widely criticized by experts, including the country’s former health minister, who resigned shortly after its release. 

In early October, a University of Oxford research team received funding from Cancer Research UK to develop the first vaccine against ovarian cancer. The vaccine would train the immune system to recognize proteins on the surface of ovarian cancer cells to fight the disease in its earliest stages. Although some people celebrated the news, social media posts reporting on the study were flooded with conspiracy theories and anti-vaccine claims. Many posts claimed without evidence that the not-yet-developed vaccine is dangerous, while others rejected vaccines outright. A few posts also circulated the myth that vaccines cause cancer.

Read the fact checks: 

• USA Today: False claim that study found myocarditis only after vaccine, not COVID-19 
• University of Colorado: Top Vaccines For Older Adults to Consider and Why 
• Cancer Research Institute: Cancer Vaccines: Preventive, Therapeutic, Personalized

---

What’s happening in the Northeast:

A New Jersey-based “medical freedom” organization claimed in a popular social media post that older adult patients are being given recommended vaccines against the flu, COVID-19,  pneumonia, and RSV without informed consent. The claims are based on unsourced secondhand anecdotes. Responses to the post falsely claimed that getting multiple vaccines at the same time is unsafe and suggested that health care providers are trying to kill off elderly patients.

What’s happening in the South:

A widely circulated social media post claimed that a college baseball player died of a sudden cardiac arrest after being forced to get a COVID-19 vaccine. According to the athlete’s obituary, he died five months after leaving the university, which reportedly required him to be vaccinated to play. The post gained traction quickly, garnering nearly 50,000 engagements and over 1,000 comments. Many responses claim without evidence that COVID-19 vaccination was responsible for the death and expressed outrage at the university’s vaccine policy.

What’s happening in the Midwest:

An Illinois-based medical professional society launched a campaign called “Adults Need Vaccines Too” to raise awareness about the importance of adult vaccination. The initiative aims to educate the public about recommended vaccines for adults and encourage more adults to stay up to date on their vaccinations to protect themselves and their communities. A social media post announcing the campaign received over 150 comments, including some claiming that vaccines are ineffective, unsafe, and unnecessary. Some posts insinuate that adults are ignoring vaccine recommendations because of distrust of COVID-19 vaccines. 

What’s happening in the West:

On October 9, a federal appeals court reinstated a Montana law that prohibits employers from discriminating based on vaccination status, including in health care settings. The court’s decision has been widely celebrated on social media, with many calling it a victory for freedom of choice and saying “it’s about time.” A prominent anti-vaccine figure celebrated the ruling on social media, referring to vaccination as an injection of “poison.” 

---

Recommendations for public health professionals 

Each week the Infodemiology.com team will provide messaging recommendations in response to some of the trending narratives outlined above. These helpful tips can be used when creating content, updating web pages and FAQs, and to inform strategy for messaging about vaccines.

Concerns about heart inflammation remain a major factor in COVID-19 vaccine hesitancy among parents. Debunking messaging may emphasize that the preprint study currently circulating online did not compare heart inflammation rates after vaccination and after infection, nor did it analyze data that would have allowed any conclusions to be made about heart inflammation risk after COVID-19 infection. Messaging may also explain that many large-scale studies have shown that COVID-19 vaccines are safe, serious adverse reactions are extremely rare, and the risk of cardiac complications is far higher after COVID-19 infection than after COVID-19 vaccination.

The claims in the Slovakian government report are not backed by science but are instead based on conspiracy theories. Messaging may highlight the March 2023 FDA and CDC letter countering similar misleading claims made by the Florida Department of Health. Debunking messaging may emphasize that all approved COVID-19 vaccines are safe and none alter recipients’ DNA. After over four years of research and monitoring, no widespread safety concerns related to mRNA vaccines have been identified. 

False claims and conspiracy theories about cancer and vaccines have circulated for decades. Messaging may explain that scientists are developing vaccines to specifically recognize and fight cancer cells, including rare, aggressive, and difficult-to-treat cancers. If developed, the experimental ovarian cancer vaccine will go through rigorous safety and clinical trials before being considered for approval. 

Interested in recommendations tailored to health care providers? Click here.