Maketa Vivi, Mavoko Hypolite Muhindo, da Luz Raquel Inocêncio, Zanga Josué, Lubiba Joachim, Kalonji Albert, Lutumba Pascal, Van Geertruyden Jean-Pierre
Department of Tropical Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo.
International Health Unit, Faculty of Medicine, University of Antwerp, Antwerp, Belgium.
Malar J. 2015 Feb 18;14:83. doi: 10.1186/s12936-015-0595-5.
Malaria is preventable and treatable when recommended interventions are properly implemented. Thus, diagnosis and treatment focus on symptomatic individuals while asymptomatic Plasmodium infection (PI) plays a role in the sustainability of the transmission and may also have an impact on the morbidity of the disease in terms of anaemia, nutritional status and even cognitive development of children. The objective of this study was to assess PI prevalence and its relationship with known morbidity factors in a vulnerable but asymptomatic stratum of the population.
A simple random sample, household survey in asymptomatic children under the age of five was conducted from April to September 2012 in two health areas of the health zone of Mont Ngafula 1, Kinshasa, Democratic Republic of Congo.
The PI prevalence were 30.9% (95% CI: 26.5-35.9) and 14.3% (95% CI: 10.5-18.1) in Cité Pumbu and Kindele health areas, respectively, (OR: 2.7; p <0.001). All were Plasmodium falciparum infected and 4% were co-infected with Plasmodium malariae. In Cité Pumbu and Kindele, the prevalence of anaemia (haemoglobin <11 g/dL) was 61.6% (95% CI: 56.6-66.5) and 39.3% (95% CI: 34.0-44.6), respectively, (OR: 2.5; p <0.001). The health area of Cité Pumbu had 32% (95% CI: 27.5-37.0) of chronic malnutrition (HAZ score ≤ -2SD) compared to 5.1% (95% CI: 2.8-7.6) in Kindele. PI was predictor factor for anaemia (aOR: 3.5, p =0.01) and within infected children, there was an inverse relationship between parasite density and haemoglobin level (β = -5*10(-5), p <0.001). Age older than 12 months (aOR: 3.8, p = 0.01), presence of anaemia (aOR: 3.4, p =0.001), chronic malnutrition (aOR: 1.8, p = 0.01), having a single parent/guardian (aOR: 1.6, p =0.04), and the non-use of insecticide-treated nets (aOR: 1.7, p = 0.04) were all predictors for PI in the overall population.
PI in asymptomatic children was correlated with anaemia and chronic malnutrition and was thus a harmful condition in the study population. Malaria control initiatives should not only focus on treatment of symptomatic infections but also take into consideration asymptomatic but infected children.
当推荐的干预措施得到妥善实施时，疟疾是可预防和可治疗的。因此，诊断和治疗主要针对有症状的个体，而无症状疟原虫感染（PI）在疟疾传播的持续性中发挥作用，并且在贫血、营养状况甚至儿童认知发育方面可能也会对疾病的发病率产生影响。本研究的目的是评估在一个易受影响但无症状的人群阶层中PI的患病率及其与已知发病因素的关系。
2012年4月至9月，在刚果民主共和国金沙萨蒙恩加富拉1卫生区的两个健康区域，对五岁以下无症状儿童进行了一项简单随机抽样的家庭调查。
在蓬布城和金代勒健康区域，PI患病率分别为30.9%（95%置信区间：26.5 - 35.9）和14.3%（95%置信区间：10.5 - 18.1），（比值比：2.7；p <0.001）。所有感染均为恶性疟原虫，4%同时感染了三日疟原虫。在蓬布城和金代勒，贫血（血红蛋白<11 g/dL）患病率分别为61.6%（95%置信区间：56.6 - 66.5）和39.3%（95%置信区间：34.0 - 44.6），（比值比：2.5；p <0.001）。蓬布城健康区域有32%（95%置信区间：27.5 - 37.0）的儿童存在慢性营养不良（身高别体重Z评分≤ -2标准差），而金代勒为5.1%（95%置信区间：2.8 - 7.6）。PI是贫血的预测因素（校正后比值比：3.5，p =0.01），在感染儿童中，寄生虫密度与血红蛋白水平呈负相关（β = -5×10⁻⁵，p <0.001）。年龄大于12个月（校正后比值比：3.8，p = 0.01）、存在贫血（校正后比值比：3.4，p =0.001）、慢性营养不良（校正后比值比：1.8，p = 0.01）、有单亲/监护人（校正后比值比：1.6，p =0.04）以及未使用经杀虫剂处理的蚊帐（校正后比值比：1.7，p = 0.04）均为总体人群中PI的预测因素。
无症状儿童中的PI与贫血和慢性营养不良相关，因此在研究人群中是一种有害状况。疟疾控制举措不仅应侧重于治疗有症状的感染，还应考虑无症状但感染的儿童。
