Adeleke Monsuru A, Mafiana Chiedu F, Sam-Wobo Sammy O, Olatunde Ganiyu O, Ekpo Uwem F, Akinwale Olaoluwa P, Toe Laurent
Molecular Parasitology Laboratory, Public Health Division, Nigerian Institute of Medical Reseach, P,M,B 2013, Yaba, Lagos, Nigeria.
Parasit Vectors. 2010 Oct 7;3:93. doi: 10.1186/1756-3305-3-93.
Studies on biting behaviours and infectivity status of insect vectors are pre-requisites in understanding the epidemiology of the vector- borne diseases and planning effective control measures. A longitudinal study was carried out to investigate the transmission index of Simulium damnosum complex species along Osun River, South Western Nigeria. Adult flies were collected on human attractants from 07:00 to 18:00 hours for two consecutive days from February 2008 to June 2009 at three communities: Osun Eleja, Osun Ogbere and Osun Budepo. The infectivity rate was determined by dissection and Polymerase Chain Reaction amplification (PCR) of 0-150 genes of Onchocerca parasite using the pool screening technique.
The results indicated that the majority of the flies collected at the three sampling points were nulliparous as they accounted for 53.90%, 57.86% and 59.58% of the flies dissected at Osun Budepo, Osun Ogbere and Osun Eleja, respectively. The parous rate was higher during the dry season than the wet season but the difference was not statistically significant (p < 0.05). The biting activity of the parous flies showed two peaks at Osun Budepo and three peaks at Osun Eleja and Osun Ogbere. Of the 1,472 flies dissected and 1,235 flies screened by molecular method, none was infected with Onchocerca parasite at the three sampling points however the annual biting rates at the three communities were higher than 1,000 considered as tolerable value for a person living in an onchocerciasis zone by Word Health Organization.
The study has provided the baseline data for further study on onchocerciasis transmission dynamics and the need to intercept man- simuliid vector contact at the study area.
对昆虫媒介的叮咬行为和感染状况进行研究，是了解媒介传播疾病流行病学和规划有效控制措施的先决条件。在尼日利亚西南部的奥孙河沿岸开展了一项纵向研究，以调查恶蚋复合体物种的传播指数。2008年2月至2009年6月期间，连续两天在07:00至18:00时，于奥孙埃莱贾、奥孙奥格贝雷和奥孙布德波三个社区，利用人体诱饵收集成年苍蝇。采用混合样本筛查技术，通过解剖和对盘尾丝虫寄生虫的0 - 150个基因进行聚合酶链反应扩增（PCR）来确定感染率。
结果表明，在三个采样点收集的大部分苍蝇为未产卵的，分别占在奥孙布德波、奥孙奥格贝雷和奥孙埃莱贾解剖苍蝇的53.90%、57.86%和59.58%。产卵率在旱季高于雨季，但差异无统计学意义（p < 0.05）。已产卵苍蝇的叮咬活动在奥孙布德波出现两个高峰，在奥孙埃莱贾和奥孙奥格贝雷出现三个高峰。在解剖的1472只苍蝇和通过分子方法筛查的1235只苍蝇中，三个采样点均未发现感染盘尾丝虫寄生虫，然而三个社区的年叮咬率均高于1000，世界卫生组织认为这是生活在盘尾丝虫病流行区的人的可耐受值。
该研究为进一步研究盘尾丝虫病传播动态以及在研究区域阻断人与蚋类媒介接触的必要性提供了基线数据。
