Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.
School of Health Sciences, Kirinyaga University, Kerugoya, Kenya.
Trop Med Int Health. 2019 May;24(5):647-656. doi: 10.1111/tmi.13223. Epub 2019 Mar 18.
Kenya has, in the last decade, made tremendous progress in the fight against malaria. Nevertheless, continued surveillance of the genetic diversity and population structure of Plasmodium falciparum is required to refine malaria control and to adapt and improve elimination strategies. Twelve neutral microsatellite loci were genotyped in 201 P. falciparum isolates obtained from the Kenyan-Ugandan border (Busia) and from two inland malaria-endemic sites situated in western (Nyando) and coastal (Msambweni) Kenya. Analyses were done to assess the genetic diversity (allelic richness and expected heterozygosity, [H ]), multilocus linkage disequilibrium ( ) and population structure. A similarly high degree of genetic diversity was observed among the three parasite populations surveyed (mean H = 0.76; P > 0.05). Except in Msambweni, random association of microsatellite loci was observed, indicating high parasite out-breeding. Low to moderate genetic structure (F = 0.022-0.076; P < 0.0001) was observed with only 5% variance in allele frequencies observed among the populations. This study shows that the genetic diversity of P. falciparum populations at the Kenyan-Ugandan border is comparable to the parasite populations from inland Kenya. In addition, high genetic diversity, panmixia and weak population structure in this study highlight the fitness of Kenyan P. falciparum populations to successfully withstand malaria control interventions.
在过去的十年中，肯尼亚在抗击疟疾方面取得了巨大进展。然而，为了完善疟疾控制措施，并调整和改进消除策略，仍需继续监测恶性疟原虫的遗传多样性和种群结构。在肯尼亚-乌干达边境（布西亚）和肯尼亚西部内陆（Nyando）和沿海（Msambweni）的两个疟疾流行地区，对 201 个恶性疟原虫分离株进行了 12 个中性微卫星基因座的基因分型。进行了分析以评估遗传多样性（等位基因丰富度和预期杂合度[H]）、多位点连锁不平衡（）和种群结构。在所调查的三个寄生虫种群中观察到了同样高的遗传多样性（平均 H=0.76；P>0.05）。除了 Msambweni 之外，还观察到微卫星基因座的随机关联，表明寄生虫的异交率较高。遗传结构低至中等（F=0.022-0.076；P<0.0001），仅在种群之间观察到 5%的等位基因频率差异。本研究表明，肯尼亚-乌干达边境的恶性疟原虫种群的遗传多样性与肯尼亚内陆的寄生虫种群相当。此外，本研究中高遗传多样性、混合交配和弱种群结构突出了肯尼亚恶性疟原虫种群对成功抵御疟疾控制干预的适应能力。
