Analysis of influenza vaccine coverage in the Coastal Plain region of the State of Piauí, from 2015 to 2020 . Research, Society and Development, [S. l.], v. 10, n. 15, p. e59901523543, 2021. DOI: 10.33448/rsd-v10i15.23543. Disponível em: https://rsdjournal.org/rsd/article/view/23543. Acesso em: 5 dec. 2025.