Epidemiological and serological aspects of hepatitis A among children and teenagers in the city of Santos: a cross-sectional study - Ciaccia, Maria Célia Cunha; Moreira, Regina Célia; Ferraro, Alexandre Archanjo; Lemos, Marcílio Figueiredo; Oba, Isabel Takano; Porta, Gilda (São Paulo Medical Journal, 2012)