Laboratory of Biochemistry, Faculty of Science, The University of Bamenda, Bambili, Cameroon.
Organisation de coordination pour la lutte contre les Endémies en Afrique Centrale, OCEAC Yaoundé, Yaounde, Cameroon.
Malar J. 2024 Aug 13;23(1):243. doi: 10.1186/s12936-024-05013-x.
In endemic locations, asymptomatic malaria is a major contribution to the rise in clinical malaria. In order to achieve the goal of interrupting malaria transmission, control programmes should take into consideration carriers of asymptomatic malaria parasite. Hence, the purpose of this study was to look at the prevalence and risk factors of asymptomatic malaria in children in Nkwen village.
Using a cross-sectional and community-based design, conducted between June and December 2022, a total of 246 children were enrolled after obtaining informed and signed consent from parents and/ or guardians. To collect data, pre-tested, closed-ended, structured questionnaires were used, ensuring the accuracy and reliability of the information gathered. A digital thermometer with infrared forehead capability was used to take participants' body temperature, providing precise measurements and respondents with temperature < 37.5 °C, and not presenting any symptoms or indicators of malaria were included in the study, ensuring the focus on asymptomatic cases. Blood samples were collected by venipuncture and screened for the presence of asymptomatic parasitaemia using blood smear microscopy and nested polymerase chain reaction (PCR). Data was entered into Microsoft Excel worksheet and analysed using SPSS version 23 software. Logistic regression models were carried out to explore the risk factors associated with asymptomatic malaria at household and individual levels and statistically significant association was considered at a p-value < 0.05.
A total of 246 healthy children were examined for asymptomatic malaria infection using microscopy and PCR. Of the examined children, 65.9% (162/246) were malaria positive by PCR while 59.3% (146/246) were malaria positive by microscopy. Considering both diagnostic methods, females had a greater prevalence of asymptomatic malaria than males. In logistic analysis, the risk of developing asymptomatic malaria was associated several factors: previous malaria episode (OR = 5.14; CI 2.94-9.01), family history of malaria (OR = 3.86; CI 2.21-6.74), homestead near swampy areas (OR = 3.56; CI 2.10-10.61), non-utilization of insecticide treated nets (OR = 4.36; CI 2.53-7.5), non-usage of indoor residual spray (IRS) (OR = 6.67; CI 3.75-11.86) and opened eaves (OR = 3.86; CI 2.21-6.74). No associations were established between asymptomatic malaria and the following factors: age group (p > 0.05), gender (p > 0.05) and type of wall construction (p > 0.05).
The high rate of asymptomatic malaria in this study is a significant problem and may jeopardize the current malaria control effort. Personal and house-level risk factors were linked with asymptomatic malaria. Therefore, it should be considered when evaluating and restructuring more successful malaria elimination tactics to accomplish the intended goals of malaria control.
在流行地区，无症状疟疾是临床疟疾上升的主要原因。为了实现阻断疟疾传播的目标，控制规划应考虑无症状疟原虫携带者。因此，本研究的目的是观察恩克文村儿童中无症状疟疾的流行率和危险因素。
采用横断面和基于社区的设计，于 2022 年 6 月至 12 月进行，在获得父母和/或监护人的知情同意后，共纳入 246 名儿童。为了收集数据，使用了经过预测试的封闭式、结构化问卷，确保了所收集信息的准确性和可靠性。使用具有红外额头功能的数字温度计测量参与者的体温，提供了精确的测量值和体温<37.5°C的测量值，并且没有出现任何疟疾症状或指标的参与者被纳入研究，以确保重点关注无症状病例。通过静脉穿刺采集血样，并使用血涂片显微镜检查和巢式聚合酶链反应（PCR）筛查无症状寄生虫血症。数据输入 Microsoft Excel 工作表，并使用 SPSS 版本 23 软件进行分析。进行逻辑回归模型，以探索家庭和个体层面与无症状疟疾相关的危险因素，并且认为 p 值<0.05 时具有统计学意义。
使用显微镜和 PCR 检查了 246 名健康儿童的无症状疟疾感染情况。在所检查的儿童中，65.9%（162/246）通过 PCR 检测为疟疾阳性，59.3%（146/246）通过显微镜检测为疟疾阳性。考虑到两种诊断方法，女性的无症状疟疾患病率高于男性。在逻辑分析中，发生无症状疟疾的风险与以下因素相关：既往疟疾发作（OR=5.14；CI 2.94-9.01）、疟疾家族史（OR=3.86；CI 2.21-6.74）、住所靠近沼泽地（OR=3.56；CI 2.10-6.71）、未使用驱虫蚊帐（OR=4.36；CI 2.53-7.5）、未使用室内滞留喷雾（IRS）（OR=6.67；CI 3.75-11.86）和开放的屋檐（OR=3.86；CI 2.21-6.74）。无症状疟疾与以下因素之间没有关联：年龄组（p>0.05）、性别（p>0.05）和墙壁结构类型（p>0.05）。
本研究中无症状疟疾的高发病率是一个严重的问题，可能危及当前的疟疾控制工作。个人和家庭层面的危险因素与无症状疟疾有关。因此，在评估和重组更成功的疟疾消除策略以实现疟疾控制的既定目标时，应考虑这些因素。
