This week, Children’s Health Defense backed a lawsuit against its founder, Health and Human Services Secretary Robert F. Kennedy Jr., alleging he “has failed” to comply with federal law by not creating a federal task force seeking the development of “safer” childhood vaccines.

The mercury-based ingredient has prompted concerns from some organizations, although the CDC has said there is no evidence it causes harm.

A nonprofit anti-vaccine group founded by Robert F. Kennedy Jr. is suing him, in his capacity as secretary of the US Department of Health and Human Services, for failing to establish a task force to promote the development of safer childhood vaccines.

What is thimerosal, does it have side effects and why is RFK Jr. removing the controversial preservative from the flu shot? Here's what to know.

The US Department of Health and Human Services has adopted a recommendation to remove a preservative called thimerosal from all influenza vaccines distributed in the United States.

While few shots still contain thimerosal, the move eliminates a vaccine option for Americans and is a win for the anti-vaccine movement.

The Wisconsin DHS added a requirement for the 2024-25 school year for the Meningococcal conjugate vaccine (MenACWY) by seventh grade, and a booster by 12th grade. Meningococcal disease is a rare, but serious disease that can be fatal in 10% to 15% of people who get it.