1Basic Science Laboratory, U.S. Army Medical Research Directorate-Africa/Kenya Medical Research Institute, Kisumu, Kenya.
2Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, Maryland.
Am J Trop Med Hyg. 2021 Jun 7;105(1):159-166. doi: 10.4269/ajtmh.21-0012.
Asymptomatic malarial parasitemia represents the largest reservoir of infection and transmission, and the impact of coinfection with HIV-1 on this reservoir remains incompletely described. Accordingly, we sought to determine the prevalence of asymptomatic malarial parasitemia in Kombewa, Western Kenya, a region that is endemic for both malaria and HIV-1. A total of 1,762 dried blood spots were collected from asymptomatic adults in a cross-sectional study. The presence of parasitemia was first determined by a sensitive Plasmodium genus-specific 18S assay, followed by less sensitive species-specific DNA-based quantitative polymerase chain reaction (PCR) assays. The prevalence of asymptomatic malarial parasitemia by 18S genus-specific PCR assay was 64.4% (1,134/1,762). Of the 1,134 malaria positive samples, Plasmodium falciparum was the most prevalent species (57.4%), followed by Plasmodium malariae (3.8%) and Plasmodium ovale (2.6%) as single or mixed infections. As expected, the majority of infections were below the detection limit of microscopy and rapid diagnostic tests. HIV-1 prevalence was 10.6%, and we observed a significant association with malarial parasitemia by χ2 analysis (P = 0.0475). Seventy-one percent of HIV-1 infected volunteers were positive for Plasmodium 18S (132/186), with only 29% negative (54/186). In HIV-1-negative volunteers, the proportion was lower; 64% were found to be positive for 18S (998/1,569) and 36% were negative (571/1,569). Overall, the prevalence of asymptomatic malarial parasitemia in Western Kenya is high, and knowledge of these associations with HIV-1 infection are critically important for malaria elimination and eradication efforts focused on this important reservoir population.
无症状疟原虫血症代表着最大的感染和传播源，而 HIV-1 合并感染对此感染源的影响仍不完全清楚。因此，我们试图确定肯尼亚西部 Kombewa 地区无症状疟原虫血症的流行率，该地区既是疟疾又是 HIV-1 的流行区。在一项横断面研究中，共采集了 1762 份无症状成人的干血斑。首先通过敏感的疟原虫属特异性 18S 检测来确定是否存在疟原虫血症，然后使用不太敏感的种特异性 DNA 定量聚合酶链反应（PCR）检测。18S 属特异性 PCR 检测无症状疟原虫血症的流行率为 64.4%（1134/1762）。在 1134 例疟原虫阳性样本中，最常见的疟原虫种是恶性疟原虫（57.4%），其次是间日疟原虫（3.8%）和卵形疟原虫（2.6%），为单一或混合感染。正如预期的那样，大多数感染的显微镜和快速诊断检测都低于检测限。HIV-1 的流行率为 10.6%，我们通过 χ2 分析观察到与疟原虫血症有显著相关性（P = 0.0475）。71%的 HIV-1 感染志愿者 18S 呈阳性（132/186），只有 29%为阴性（54/186）。在 HIV-1 阴性志愿者中，比例较低；18S 阳性率为 64%（998/1569），阴性率为 36%（571/1569）。总的来说，肯尼亚西部无症状疟原虫血症的流行率很高，了解这些与 HIV-1 感染的关联对于针对这一重要感染源人群开展的疟疾消除和根除工作至关重要。
