Soniran Olajoju T, Idowu Olufunmilayo A, Ogundapo Segun S
Biology Research Unit, Akanu Ibiam Federal Polytechnic, Unwana, Ebonyi State, Nigeria.
Pure and Applied Zoology Department, Federal University of Agriculture, Abeokuta, Ogun State, Nigeria.
Malariaworld J. 2017 Aug 1;8:13. eCollection 2017.
Antimalarial drug-resistant strains have been a major obstacle to the global efforts of controlling and eliminating malaria. The hope of reintroducing chloroquine for the treatment of uncomplicated malaria follows recent reports on decreases in the prevalence of chloroquine-resistant in several countries and recently, its total disappearance in Malawi and Zambia. In Nigeria, the discontinued use of chloroquine for malaria treatment was officially announced in 2005. A few available reports have shown a persistent high prevalence of the major biomarker of chloroquine resistance in southwest Nigeria. However, information on its prevalence in rural and urban areas is scanty. We investigated possible factors associated with the prevalence of a biomarker for chloroquine-resistance in Ogun State, southwest Nigeria.
Parasite DNA was extracted from dried blood spots collected by finger-prick in malaria symptomatic and asymptomatic subjects attending the urban-based State General Hospital and a rural-based Primary Health Centre. A structured questionnaire was used to collect data on malaria/fever treatment history. Nested Polymerase Chain Reaction (PCR) followed by Restriction Fragment Length Polymorphisms (RFLP) analysis was used to detect mutations in the chloroquine resistance transporter ().
Of the 243 participants recruited for this study, 56 were found to harbour parasites, of which 62.5% (35/56) showed symptoms of malaria. Prevalence of chloroquine-resistant strains ( K76T) was 69.6%. The prevalence of K76T recorded in the rural area (91.7%) was significantly higher (P<0.05) than that in the urban area (53.1%). There was no correlation between prevalence of chloroquine-resistant strains and malaria symptoms in the rural area. However, prevalence of chloroquine-resistant strains was significantly higher in malaria-symptomatic subjects from the urban area.
Drug-resistant strains recorded in the rural area were associated with self-medication and patronage of drug vendors who continue to sell chloroquine. These findings present the importance of continuous surveillance of biomarkers indicating drug resistance especially now that antimalarial drug resistance is a threat to malaria eradication.
抗疟药物耐药菌株一直是全球控制和消除疟疾努力的主要障碍。随着最近一些国家氯喹耐药率下降的报道，以及最近在马拉维和赞比亚氯喹耐药现象完全消失，重新引入氯喹治疗非复杂性疟疾的希望随之而来。在尼日利亚，2005年正式宣布停止使用氯喹治疗疟疾。少数现有报告显示，尼日利亚西南部氯喹耐药的主要生物标志物患病率持续居高不下。然而，关于其在农村和城市地区患病率的信息却很少。我们调查了尼日利亚西南部奥贡州与氯喹耐药生物标志物患病率相关的可能因素。
从在城市的州立综合医院和农村的初级卫生中心就诊的有疟疾症状和无症状受试者通过手指采血采集的干血斑中提取寄生虫DNA。使用结构化问卷收集疟疾/发热治疗史数据。采用巢式聚合酶链反应（PCR），随后进行限制性片段长度多态性（RFLP）分析，以检测氯喹耐药转运蛋白（）中的突变。
在本研究招募的243名参与者中，发现56人携带疟原虫，其中62.5%（35/56）有疟疾症状。氯喹耐药菌株（K76T）的患病率为69.6%。农村地区记录的K76T患病率（91.7%）显著高于城市地区（53.1%）（P<0.05）。农村地区氯喹耐药菌株的患病率与疟疾症状之间没有相关性。然而，城市地区有疟疾症状的受试者中氯喹耐药菌株的患病率显著更高。
农村地区记录的耐药疟原虫菌株与自我用药以及继续销售氯喹的药品供应商的光顾有关。这些发现表明持续监测指示耐药性的生物标志物的重要性，尤其是现在抗疟药物耐药性对疟疾根除构成威胁的情况下。
