The Acre Project: the epidemiology of malaria and arthropod-borne virus infections in a rural Amazonian population

• Published in: Cadernos de saúde pública Vol. 22; no. 6; pp. 1325 - 1334
• Main Authors: Silva-Nunes, Mônica da, Malafronte, Rosely dos Santos, Luz, Bruna de Almeida, Souza, Estéfano Alves de, Martins, Lívia Carício, Rodrigues, Sueli Guerreiro, Chiang, Jannifer Oliveira, Vasconcelos, Pedro Fernando da Costa, Muniz, Pascoal Torres, Ferreira, Marcelo Urbano
• Format: Journal Article
• Language: English; Portuguese
• Published: Brazil Escola Nacional de Saúde Pública Sergio Arouca, Fundação Oswaldo Cruz 01.06.2006; Escola Nacional de Saúde Pública, Fundação Oswaldo Cruz
• Subjects: Adolescent; Adult; Amazonian Ecosystem; Antibodies, Viral - blood; Arbovirus Infections; Arbovirus Infections - epidemiology; Arbovirus Infections - immunology; Arboviruses; Arboviruses - immunology; Brazil - epidemiology; Child; Child, Preschool; Cross Reactions; Dengue; Dengue Virus - immunology; Ecosystem; Endemic Diseases; Enzyme-Linked Immunosorbent Assay; Female; Humans; Immunoglobulin G - blood; Infant; Malaria; Malaria - epidemiology; Malaria - immunology; Male; Middle Aged; Prevalence; PUBLIC, ENVIRONMENTAL & OCCUPATIONAL HEALTH; Rural Population; Seroepidemiologic Studies; Sex Factors; Brazil; Ecossistema Amazônico; Malaria; Arbovirus Infections; Arbovírus; Amazonian Ecosystem; Dengue; Arboviruses; Infecções por Arbovirus; Malária
• ISSN: 0102-311X; 1678-4464; 1678-4464; 0102-311X
• DOI: 10.1590/S0102-311X2006000600021

The authors describe the baseline malaria prevalence and arbovirus seroprevalence among 467 subjects in an ongoing cohort study in rural Amazonia. Most subjects (72.2%) reported one or more previous episodes of malaria, and 15.6% had been hospitalized for malaria, but only 3.6% of individuals five years or older had malaria parasites detected by microscopy (10 with Plasmodium vivax and 4 with P. falciparum). Antibodies to Alphavirus, Orthobunyavirus, and/or Flavivirus were detected by hemagglutination inhibition (HI) in 42.6% of subjects aged five years or older, with a higher seropositivity rate among males (49.2%) than females (36.2%). Since 98.9% of subjects had been immunized for yellow fever, the presence of cross-reactive antibodies to dengue and other Flaviviruses cannot be ruled out, but at least 12 subjects (3.3%) with IgM antibodies to dengue virus detected by ELISA had a putative recent exposure to this virus.