Maricelma Fialho is an indigenous leader of the Terena people, born in the village of Bananal, Mato Grosso do Sul, Brazil. She is a biomedical doctor, master and PhD student in Infectious and Parasitic Diseases at the Faculty of Medicine of the Federal University of Mato Grosso do Sul (UFMS). Maricelma is dedicated to research into infectious diseases, with an emphasis on fungi that cause systemic mycoses, which mainly affect rural indigenous communities.

During the COVID-19 pandemic, Maricelma established partnerships with institutions and managed to distribute alcoholic beverages and food to indigenous villages, benefiting hundreds of families. Additionally, she is treasurer of the Terena Institute of Intercultural Education and a volunteer for the Brazilian Red Cross, working as a translator of the Terena Language.

Representing Brazil at the Youth Leadership Coalition (IYLC) Latin America, Maricelma participates in global discussions on civic and political participation. Her efforts include educational initiatives and distribution of computer equipment to promote digital inclusion. Maricelma also organizes sporting events in her Bananal village, with a focus on reducing alcohol and tobacco consumption among young indigenous people. Its main objectives are to improve basic sanitation, indigenous health, offer English courses and improve sports infrastructure for young people.