title: The Acre Project: the epidemiology of malaria and arthropod-borne virus infections in a rural Amazonian population.
abstract: 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.
authors.affiliation: Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil.
authors.forename: Mônica da
authors.initials: Md
authors.lastname: Silva-Nunes
authors.forename: Rosely dos Santos
authors.initials: Rdos S
authors.lastname: Malafronte
authors.forename: Bruna de Almeida
authors.initials: Bde A
authors.lastname: Luz
authors.forename: Estéfano Alves de
authors.initials: EA
authors.lastname: Souza
authors.forename: Lívia Carício
authors.initials: LC
authors.lastname: Martins
authors.forename: Sueli Guerreiro
authors.initials: SG
authors.lastname: Rodrigues
authors.forename: Jannifer Oliveira
authors.initials: JO
authors.lastname: Chiang
authors.forename: Pedro Fernando da Costa
authors.initials: PF
authors.lastname: Vasconcelos
authors.forename: Pascoal Torres
authors.initials: PT
authors.lastname: Muniz
authors.forename: Marcelo Urbano
authors.initials: MU
authors.lastname: Ferreira
mesh_terms: D000293:Adolescent; D000328:Adult; D000914:Antibodies, Viral / Q000097:blood; D001102:Arbovirus Infections / Q000453:epidemiology* / Q000276:immunology; D001103:Arboviruses / Q000276:immunology; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D003429:Cross Reactions; D003716:Dengue Virus / Q000276:immunology; D017753:Ecosystem; D019353:Endemic Diseases; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007223:Infant; D008288:Malaria / Q000453:epidemiology* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012424:Rural Population; D016036:Seroepidemiologic Studies; D012737:Sex Factors
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G