Autor(es):
Viana, Giselle Maria Rachid ; Silva-Flannery, Luciana ; Barbosa, Danielle Regina Lima ; Lucchi, Naomi ; Valle, Suiane Costa Negreiros do ; Farias, Samela ; Barbalho, Nayara ; Marchesini, Paola ; Rossi, Juliana Chedid Nogaredi ; Udhayakumar, Venkatachalam ; P?voa, Marinete Marins ; Oliveira, Alexandre Macedo de
Data: 2018
Origem: Oasisbr
Assunto(s): Mal?ria / diagn?stico; Mal?ria Falciparum / parasitologia; Mal?ria Vivax / parasitologia; Rea??o em Cadeia da Polimerase em Tempo Real / m?todos; T?cnicas de Amplifica??o de ?cido Nucleico / m?todos; T?cnicas e Procedimentos Diagn?sticos; Sensibilidade e Especificidade; Brasil / epidemiologia; Regi?o Norte; Cruzeiro do Sul (AC)
Descrição
This study was supported by the Amazon Malaria Initiative, which is funded by the United States Agency for International Development (USAID)
Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Ananindeua, PA, Brasil.
Centers for Disease Control and Prevention. Centers for Global Health. Division of Parasitic Diseases and Malaria. Malaria Branch. Atlanta, GA, United States of America.
Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Ananindeua, PA, Brasil.
Centers for Disease Control and Prevention. Centers for Global Health. Division of Parasitic Diseases and Malaria. Malaria Branch. Atlanta, GA, United States of America.
Secretaria Estadual de Sa?de do Acre. Hemon?cleo Cruzeiro do Sul. Cruzeiro do Sul, AC, Brasil.
Secretaria Estadual de Sa?de do Acre. Hemon?cleo Cruzeiro do Sul. Cruzeiro do Sul, AC, Brasil.
Secretaria Estadual de Sa?de do Acre. Hemon?cleo Cruzeiro do Sul. Cruzeiro do Sul, AC, Brasil.
Coordena??o Geral do Programa Nacional de Controle da Mal?ria e Doen?as Transmitidas pelo Aedes. Bras?lia, DF, Brasil.
Coordena??o Geral do Programa Nacional de Controle da Mal?ria e Doen?as Transmitidas pelo Aedes. Bras?lia, DF, Brasil.
Centers for Disease Control and Prevention. Centers for Global Health. Division of Parasitic Diseases and Malaria. Malaria Branch. Atlanta, GA, United States of America.
Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Ananindeua, PA, Brasil.
Centers for Disease Control and Prevention. Centers for Global Health. Division of Parasitic Diseases and Malaria. Malaria Branch. Atlanta, GA, United States of America.
Conventional molecular methods, such as nested polymerase chain reaction (PCR), are very sensitive for detection of malaria parasites, but require advanced laboratory equipment and trained personnel. Real-time loop-mediated isothermal amplification (RealAmp), a loopmediated isothermal amplification-based molecular tool (LAMP), facilitates rapid target amplification at a single temperature setting, reducing the need for sophisticated equipment. We evaluated the performance of a field-adapted RealAmp assay for malaria diagnosis in Cruzeiro do Sul, Acre State, Brazil, a remote area in Brazil with limited laboratory capabilities. We enrolled 1,000 patients with fever (axillary temperature 37.5 C) or history of fever in last 24 h presenting for malaria diagnosis from February through June 2015. DNA was extracted from dried blood spots using a boil and spin method (heat treatment) at the sample processing site, and also using commercial kits at a Brazilian national reference laboratory. RealAmp was performed for Plasmodium genus, P. falciparum, and P. vivax identification. In addition, Giemsa-stained blood smears were prepared and examined by two independent well-trained study microscopists. A combination of Real-time PCR and nested PCR was used as reference test. The sensitivity and specificity of RealAmp in the field site laboratory were 94.1% (95% confidence interval [CI]: 90.1?96.8) and 83.9% (95% CI: 81.1?86.4), respectively. The sensitivity and specificity of local microscopy were 87.7% (95% CI: 82.6? 91.7) and 98.9% (95% CI: 97.8?99.4), respectively, while study microscopy showed sensitivity of 96.4% (95% CI: 93.0?98.4) and specificity of 98.2% (95% CI: 97.0?99.0). None of the three tests detected 20 P. falciparum and P. vivax mixed infections identified by the reference test. Our findings highlight that it is possible to implement simple molecular tests in facilities with limited resources such as Cruzeiro do Sul in Brazil. RealAmp sensitivity was similar to that of microscopy performed by skilled professionals; both RealAmp and study microscopy performed poorly in detection of mixed infection. Attempts to develop and evaluate simpler molecular tools should continue, especially for the detection of malaria infection in remote areas.
