Data Deficit: Are Covid-19 vaccines safe for men under age 40?

Challenge:
- On October 7, Florida Surgeon General Dr. Joseph A. Ladapo announced that he recommends males aged 18-39 not receive the Covid-19 mRNA vaccine, citing concern of increased risk of cardiac-related death.
- This recommendation is based on a study of Florida residents that suggested, “mRNA vaccination may be driving the increased risk in males, especially among males aged 18 – 39” but ultimately concluded that “risk for both all-cause and cardiac-related deaths was substantially higher 28 days following COVID-19 infection.”
- The study was not published in a journal, does not list its authors, and is not peer reviewed.
- The Palm Beach Post reports the study has “drawn rebuke from doctors who point out his recommendation lacks evidence.”
Fuels Rumors:
- Vaccine skeptics have made many misleading claims about Covid-19 vaccines, cardiac-related death, myocarditis, and pericarditis previously.
- Dr. Ladapo’s position and credentials give him credibility that can be cited by vaccine skeptics using his recommendation to further discourage vaccination.
Data Deficits:
- Do mRNA vaccines affect heart health? Are there specific concerns men and boys should be aware of?
- What are the risks of cardiac problems after an infection with Covid-19 versus vaccination?
Data Deficit: Is it safe to breastfeed after vaccination?

Challenge:
- Vaccine skeptics omitted key context in social media posts regarding a JAMA Pediatrics study on Covid-19 vaccines and breastfeeding.
- The study discussion emphasized that “the sporadic presence and trace quantities of COVID-19 vaccine mRNA detected in EBM suggest that breastfeeding after COVID-19 mRNA vaccination is safe, particularly beyond 48 hours after vaccination.”
- The discussion later noted that “caution is warranted about breastfeeding children younger than 6 months in the first 48 hours after maternal vaccination until more safety studies are conducted.”
- Several posts – including one from JAMA Pediatrics – emphasized that “caution is warranted” in the first 48 hours, but neglected to note the study explicitly states that breastfeeding after Covid-19 vaccination is safe.
Fuels Rumors:
- Vaccine skeptics have shared misleading claims about the safety of taking the Covid-19 vaccine during pregnancy and its impacts on fertility previously.
- The JAMA Pediatrics study is easy to misconstrue, and provides a credible source for anti-vaccine activists to cite as “proof” of their misleading claims regarding vaccine safety.
Data Deficits:
- Do trace amounts of mRNA in breastmilk affect infants?
Data Deficit: Can Covid-19 vaccines make certain cancers worse?

Challenges:
- A recent piece in The Atlantic told the story of Dr. Michael Goldman, whose lymphoma worsened after receiving a Covid-19 booster shot in 2021 (note: this was not the bivalent booster).
- Dr. Goldman believes he may be the “rare unfortunate exception” regarding the safety of vaccines for cancer patients.
Fuels Rumors:
- Some anti-vaccine activists, like Dr. Ryan Cole, promote the false claim that vaccines cause cancer.
- This story – well-reported and in a mainstream outlet – can be used to give credence to false claims.
Data Deficits:
- How does vaccination impact the immune system of a healthy person? Of a person with cancer?
- Should people with certain types of cancer avoid or delay vaccination?
Data Deficit: Do childhood vaccines increase risk of asthma?

Challenges:
- STAT covered a study that “suggests there may be a link between aluminum used in vaccines that are given to young children in the first two years of life and the risk of developing asthma before age 5.”
- STAT reports the study is preliminary and that the authors “urge caution” in the interpretation of results.
- Note: This claim is not specific to Covid-19 vaccination, but rather some routine childhood vaccines.
Fuels Rumors:
- Gives new life to long-standing claims by anti-vaccine activists that aluminum is a dangerous ingredient.
Data Deficits:
- Why is aluminum an ingredient in childhood vaccines?
- Is there other, stronger evidence that it may be dangerous?
Lorraine Broertjes of the Brown University Information Futures Lab and Isabella Navia of ATI contributed reporting to this briefing.