肯尼亚西部高地在使用 ITN 前后不同年龄段间疟原虫寄生虫状况。

Age-specific Plasmodium parasite profile in pre and post ITN intervention period at a highland site in western Kenya.

机构信息

Centre for Global Health Research, Kenya Medical Research Institute (KEMRI), PO Box 1578, Kisumu, 40100, Kenya.

Kenyatta University, PO Box 43844, Nairobi, Kenya.

出版信息

Malar J. 2017 Nov 16;16(1):466. doi: 10.1186/s12936-017-2119-y.

DOI:10.1186/s12936-017-2119-y

PMID:29145842

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC5689155/

Abstract

BACKGROUND

Monitoring and evaluation of entomological, parasitological and clinical data is an important component of malaria control as it is a measure of the success of the interventions. In many studies, clinical data has been used to monitor trends in malaria morbidity and mortality. This study was conducted to demonstrate age dependent prevalence of malaria in the pre- and post-interventions period.

METHODS

A series of cross-sectional malaria parasitological surveys were conducted in Iguhu, western Kenya. Participants were randomly selected school-aged children between 6 and 13 years. The study was conducted between June 2002-December 2003 and January 2012-February 2015. Sexual and asexual parasite prevalence and densities were determined using microscopy. Age-dependence in parasite infections was compared between 2002-2003 and 2012-2015.

RESULTS

Plasmodium falciparum had the highest prevalence of 43.5 and 11.5% in the pre- and post-intervention periods. Plasmodium malariae had a prevalence of 2.3 and 0.2%, while Plasmodium ovale had a prevalence of 0.3 and 0.1% during the pre- and post-intervention period, respectively. There was a 73.7% reduction in prevalence of P. falciparum in the post-intervention compared to the pre-intervention period. Plasmodium falciparum parasite density increased by 71.2% between pre- and post-intervention period from (geometric mean of) 554.4-949.2 parasites/µl. Geometric mean gametocytaemia in Iguhu was higher in the post-intervention period (106.4 parasites/µl), when compared to the pre-intervention period (54.1 parasites/µl). Prevalence and density of P. falciparum showed a lower age-dependency during post-intervention period when compared to pre-intervention period.

CONCLUSION

The study provides evidence for reduction of malaria prevalence following the introduction of LLINs and ACT in western Kenya. Fewer people become infected but the few infected may be more infectious as suggested by higher gametocyte densities. The high parasite densities, which were not dependent on age, observed in the post intervention period imply that a more comprehensive integrated malaria management may be required to sustain the current interventions and hence reduce malaria transmission.

摘要

背景

监测和评估昆虫学、寄生虫学和临床数据是疟疾控制的重要组成部分，因为它是干预措施成功的衡量标准。在许多研究中，临床数据被用于监测疟疾发病率和死亡率的趋势。本研究旨在展示干预前后疟疾在不同年龄段的流行情况。

方法

在肯尼亚西部的 Iguhu 进行了一系列横断面寄生虫学调查。参与者是随机选择的 6 至 13 岁的学龄儿童。该研究于 2002 年 6 月至 2003 年 12 月和 2012 年 1 月至 2015 年 2 月进行。使用显微镜确定有性和无性寄生虫的流行率和密度。比较了 2002-2003 年和 2012-2015 年之间寄生虫感染的年龄依赖性。

结果

恶性疟原虫在干预前和干预后的流行率分别为 43.5%和 11.5%，最高。间日疟原虫的流行率分别为 2.3%和 0.2%，卵形疟原虫的流行率分别为 0.3%和 0.1%。干预后恶性疟原虫的流行率比干预前下降了 73.7%。恶性疟原虫寄生虫密度从干预前（几何平均值为 554.4-949.2 个/μl）到干预后增加了 71.2%。与干预前相比，Iguhu 的配子体血症几何平均值在干预后更高（106.4 个/μl）。干预后恶性疟原虫的流行率和密度比干预前的年龄依赖性低。