Akinyi Mercy Yvonne, Chifwete Margaret, Ndwiga Leonard, Kimenyi Kelvin Muteru, Osoti Victor, Ochola-Oyier Lynette Isabella
KEMRI-Wellcome Trust Research Programme, Kenya Medical Research Institute, Kilifi, P.O. Box 230, 80108, Kenya.
Institute of Primate Research, National Museums of Kenya, Nairobi, 24481-00502, Kenya.
Wellcome Open Res. 2024 Sep 17;7:207. doi: 10.12688/wellcomeopenres.17972.4. eCollection 2022.
The focus on diagnosis has led to an underestimation of the global burden of malaria resulting from neglected species. However, there is still scarce data on the prevalence of species (spp) globally. To address this knowledge gap, data collected from cross-sectional studies in Kilifi county were used to: 1) determine the prevalence of infections; and 2) determine the sensitivity of different diagnostic assays in detecting infections.
A total of 531 individuals were sampled across three study sites in Kilifi County, Kenya between 2009 and 2020. Blood smears were prepared from peripheral blood and screened for parasite stages using light microscopy. Molecular screening involved DNA extraction of dried blood spots and blood in ethylenediaminetetraacetic acid, polymerase chain reaction (PCR) using primers targeting the 18 small ribosomal subunit and sequencing.
Microscopy screening revealed that the most prevalent species was (32.0%) followed by (9.0%) and then 1.5%). PCR screening identified additional positives cases. Overall PCR results indicate that43 (8.1%) out of the 531 individuals harbored infection with the highest prevalence reported in the tertiary health facility, (14.6%, 95% CI 8-23.6%), followed by the primary health facility (8.3%, 95% CI 5.4-11.9%), and the community from a cross-sectional blood survey, (3.6%, 95% CI 1.2-8.2%). Microscopy screening for had a low sensitivity of 7% (95% CI 1-19-30%) and a high specificity of 99% (95% CI 98-100%). Sequencing results confirmed the presence of .
This study provides baseline data for surveillance in Kilifi County, primarily using PCR to improve diagnosis. These results suggest that malaria elimination and eradication efforts should not only concentrate on but should embrace a holistic approach towards elimination of all spp.
对疟疾诊断的关注导致人们低估了被忽视疟原虫种类所造成的全球疟疾负担。然而，全球范围内关于这些疟原虫种类（spp）流行情况的数据仍然稀缺。为了填补这一知识空白，我们使用了从基利菲县横断面研究中收集的数据来：1）确定疟原虫感染的流行情况；2）确定不同诊断检测方法在检测疟原虫感染方面的敏感性。
2009年至2020年间，在肯尼亚基利菲县的三个研究地点共采集了531人的样本。从外周血制备血涂片，并用光学显微镜筛查疟原虫阶段。分子筛查包括从干血斑和乙二胺四乙酸抗凝血中提取DNA，使用靶向18小核糖体亚基的引物进行聚合酶链反应（PCR）并测序。
显微镜筛查显示，最常见的疟原虫种类是 [疟原虫种类1]（32.0%），其次是 [疟原虫种类2]（9.0%），然后是 [疟原虫种类3]（1.5%）。PCR筛查发现了更多的阳性病例。总体PCR结果表明,531名个体中有43人（8.1%）感染了疟原虫，其中三级医疗机构报告的感染率最高（14.6%，95%置信区间8 - 23.6%）,其次是初级医疗机构（8.3%，95%置信区间5.4 - 11.9%），以及横断面血液调查中的社区（3.6%，95%置信区间1.2 - 8.2%）。显微镜筛查 [疟原虫种类] 的敏感性较低，为7%（95%置信区间1 - 19 - 30%），特异性较高，为99%（95%置信区间98 - 100%）。测序结果证实了 [疟原虫种类] 的存在。
本研究为基利菲县的疟原虫监测提供了基线数据，主要使用PCR来改善诊断。这些结果表明，疟疾消除和根除工作不仅应集中在 [疟原虫种类] 上，还应采取全面的方法来消除所有疟原虫种类。
