This year's flu vaccine reduced the risk of hospitalization in the Southern Hemisphere but wasn't as effective as the one used in the prior season, a new CDC study found.

What is thimerosal? Thimerosal is a preservative found in the flu vaccine to help facilitate the use of multi-dose vials without the risk of contamination. It contains a particular type of mercury.

A CDC advisory panel has recommended that the preservative thimerosal be dropped from flu vaccines, a largely symbolic move but one that could sow doubts about safety.

Advisers to the Centers for Disease Control and Prevention recommended against flu shots containing the ingredient thimerosal. Why is the additive, safely used since the 1930s, being questioned again?

Here are more takeaways from the first meeting of Kennedy’s vaccine panel. Key decisions on RSV immunizations and flu vaccines The advisers made a number of new recommendations this week.

Final Thoughts The return of vaccine-preventable diseases isn’t just about individual choices—it’s about protecting our most vulnerable.