Importance of Preventative Vaccines for Medicare Advantage Plan Holders Preventative vaccines play a crucial role in safeguarding the health and well-being of individuals, particularly for Medicare Advantage plan holders. Seniors are more vulnerable to picking up various diseases and their complications.Vaccines offer a proactive approach to disease prevention, significantly reducing the risk of infections and their associated health burdens. Influenza Vaccine Influenza (flu) vaccine is a critical preventative measure for seniors. Each year, the flu virus evolves, making it essential for individuals, especially