The influential activist recognized for advocating health rights for marginalized communities is Dr. Mona Hanna-Attisha. She played a critical role in exposing the Flint water crisis, highlighting the severe impact of lead contamination on children's health. Through her research and advocacy, she emphasized health disparities experienced by vulnerable populations and pushed for greater accountability in public health. Her efforts have inspired movements for clean water access and systemic change, championing health equity and social justice for marginalized groups.