Absztrakt
Identification of the specific Simulium species at play in the transmission of Onchocerca volvulus is important because it helps to explain the epidemiology and clinical presentation of the disease and guides in monitoring of long term impact of ivermectin treatment on onchocerciasis transmission. The study therefore sought to use molecular markers for vector identification. A combination of Polymerase Chain Reaction (PCR) assay and Restriction fragment Length polymorphism (RFLP) was used to identify members of Simulium damnosum complex in forest area of south western Nigeria. The results revealed the presence of three members of the Simulium damnosum complex: S. yahense, S. sirbanum and S. damnosum ss. S. yahense was the predominant and major vector in the study sites. This provides baseline data for future monitoring vector of human onchocerciasis in the area.
Keywords: Simulium damnosum, onchocerca volvulus, Nigeria, molecular identification
Résumé
Identification des espèces spécifiques de Simulium transmettant l’Onchocercose volvulus est important parce qu’il aide à expliquer l’épidémiologie et la présentation clinique de la maladie et guide a contrôler l’impact a long terme du traitement de l’Ivermectine sur la transmission de l’onchocercose. Cette étude utilisait les marqueurs moléculaires pour l’identification du vecteur. Une combinaison de la réaction en chaîne Polymérase (PCR) et la digestion enzymatique polymorphique (RFLP) était utilisée pour identifier les membres du Simulium damnosum complexe dans la foret au sud Ouest du Nigeria. Les résultats révélaient la présence de trios sous types de Simulium damnosum complexe: S. yahense, S. sirbanum et S. damnosum ss. S. yahense était le plus prédominant et le vecteur majeur dans les sites étudiés. Ceci apporte une donnée de base sur le contrôle future du vecteur de l’onchocercose chez l’humain dans cette région.
Correspondence: Dr. E.T. Idowu, Public Health Division, Nigerian Institute of Medical Research, PMB 2013, Yaba, Lagos, Nigeria. Email: etidowu@yahoo.com
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