Epidemiology and control of frontier malaria in Brazil: lessons from community-based studies in rural Amazonia

Autor(es):Mostrar menos -

da Silva, Natal S. ^[1] ; da Silva-Nunes, M. ^{[1, 2]} ; Malafronte, Rosely S. ^{[3, 4]} ; Menezes, Maria J. ^[1] ; D'Arcadia, Rosane R. ^[1] ; Komatsu, Natalia T. ^[1] ; Scopel, Kezia K. G. ^{[5, 1]} ; Braga, Erika M. ^[5] ; Cavasini, Carlos E. ^[6] ; Cordeiro, Jose A. ^[7] ; Ferreira, Marcelo U. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Ciencias Biomed, Dept Parasitol, BR-05508900 Sao Paulo - Brazil

^[2] Univ Fed Acre, Ctr Ciencias Saude & Desporto, Rio Branco, AC - Brazil

^[3] Inst Med Trop Sao Paulo, Lab Protozool, Sao Paulo - Brazil

^[4] Univ Sao Paulo, Fac Med, Dept Doencas Infecciosas & Parasitarias, Sao Paulo - Brazil

^[5] Univ Fed Minas Gerais, Inst Ciencias Biol, Dept Parasitol, Belo Horizonte, MG - Brazil

^[6] Fac Med Sao Jose do Rio Preto, Dept Doencas Dermatol Infecciosas & Parasitarias, Sao Jose Do Rio Preto, SP - Brazil

^[7] Fac Med Sao Jose do Rio Preto, Dept Epidemiol & Saude Colet, Sao Jose Do Rio Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Transactions of the Royal Society of Tropical Medicine and Hygiene; v. 104, n. 5, p. 343-350, MAY 2010.
• Citações Web of Science: 37

Resumo

We describe the epidemiology of malaria in a frontier agricultural settlement in Brazilian Amazonia. We analysed the incidence of slide-confirmed symptomatic infections diagnosed between 2001 and 2006 in a cohort of 531 individuals (2281.53 person-years of follow-up) and parasite prevalence data derived from four cross-sectional surveys. Overall, the incidence rates of Plasmodium vivax and P. falciparaum were 20.6/100 and 6.8/100 person-years at risk, respectively, with a marked decline in the incidence of both species (81.4 and 56.8%, respectively) observed between 2001 and 2006. PCR revealed 5.4-fold more infections than conventional microscopy in population-wide cross-sectional surveys carried out between 2004 and 2006 (average prevalence, 11.3 vs. 2.0%). Only 27.2% of PCR-positive (but 73.3% of slide-positive) individuals had symptoms when enrolled, indicating that asymptomatic carriage of low-grade parasitaemias is a common phenomenon in frontier settlements. A circular cluster comprising 22.3% of the households, all situated in the area of most recent occupation, comprised 69.1% of all malaria infections diagnosed during the follow-up, with malaria incidence decreasing exponentially with distance from the cluster centre. By targeting one-quarter of the households, with selective indoor spraying or other house-protection measures, malaria incidence could be reduced by more than two-thirds in this community. (C) 2010 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 05/51988-0 - Epidemiologia da malaria: fatores de risco, distribuicao espaco-temporal e resposta ao tratamento em uma coorte rural amazonica.
• Beneficiário: Marcelo Urbano Ferreira
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 03/09719-6 - Aquisicao de imunidade contra plasmodium vivax: estudo longitudinal em uma comunidade rural da amazonia brasileira.
• Beneficiário: Marcelo Urbano Ferreira
• Modalidade de apoio: Auxílio à Pesquisa - Regular