也门共和国乌萨卜阿斯萨菲尔地区疟疾传播高度异质性，存在大量亚临床感染且感染源多样。

High heterogeneity of malaria transmission and a large sub-patent and diverse reservoir of infection in Wusab As Safil district, Republic of Yemen.

作者信息

Cook Jackie, Grignard Lynn, Al-Eryani Samira, Al-Selwei Mustafa, Mnzava Abraham, Al-Yarie Hafed, Rand Alison, Kleinschmidt Immo, Drakeley Chris

机构信息

MRC Tropical Epidemiology Group, London School of Hygiene and Tropical Medicine, London, UK.

Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.

出版信息

Malar J. 2016 Apr 8;15:193. doi: 10.1186/s12936-016-1249-y.

BACKGROUND

Yemen remains the country with the highest malaria transmission within the Arabian Peninsula and a source of imported cases to neighbouring countries.

METHODS

This study collected samples from individuals resident in a valley in Western Yemen as a baseline to examine infection prevalence for a future trial. As well as rapid diagnostic test (RDT) and microscopy, a filter paper blood spot was collected for molecular and serological analyses.

RESULTS

Samples were collected from 2261 individuals from 12 clusters across a study area of approximately 100 km(2). Plasmodium falciparum infection prevalence was 12.4, 11.1 and 19.6% by RDT, microscopy and polymerase chain reaction (PCR), respectively. RDT and microscopy did not detect 45% of infections present, suggesting many infections were low-density. Infection prevalence and seroprevalence were highly heterogeneous between clusters, with evidence of higher exposure in clusters close to the wadi. The mean multiplicity of infection (MOI) was 2.3 and high heterozygosity and allelic richness were detected.

CONCLUSIONS

This highly diverse parasite population suggests a high degree of transmissibility and coupled with the substantial proportion of low-density infections, may pose challenges for malaria control and elimination efforts.

背景

也门仍是阿拉伯半岛疟疾传播率最高的国家，也是邻国输入性病例的来源地。

方法

本研究从也门西部一个山谷的居民中采集样本，作为未来一项试验的基线，以检测感染率。除了快速诊断检测（RDT）和显微镜检查外，还采集了滤纸血斑用于分子和血清学分析。

结果

在约100平方公里的研究区域内，从12个群组的2261个人中采集了样本。通过RDT、显微镜检查和聚合酶链反应（PCR）检测到的恶性疟原虫感染率分别为12.4%、11.1%和19.6%。RDT和显微镜检查未检测到45%的现有感染病例，这表明许多感染为低密度感染。各群组之间的感染率和血清阳性率高度不均一，有证据表明靠近干河的群组暴露风险更高。平均感染复数（MOI）为2.3，检测到高杂合性和等位基因丰富度。