PDF(Pubmed)
Abstract：
Malaria remains a public health problem in many parts of the world. In Malaysia, the significant progress towards the national elimination programme and effective disease notification on malaria has resulted in zero indigenous human malaria cases since 2018. However, the country still needs to determine the extent of malaria exposure and transmission patterns, particularly in high-risk populations. In this study, a serological method was used to measure transmission levels of Plasmodium falciparum and Plasmodium vivax among indigenous Orang Asli communities in Kelantan, Peninsular Malaysia. A community-based cross-sectional survey was conducted in three Orang Asli communities (i.e., Pos Bihai, Pos Gob, and Pos Kuala Betis) in Kelantan from June to July 2019. Antibody responses to malaria were assessed by enzyme-linked immunosorbent assay (ELISA) using two P. falciparum (PfAMA-1 and PfMSP-119) and two P. vivax (PvAMA-1 and PvMSP-119) antigens. Age-adjusted antibody responses were analysed using a reversible catalytic model to calculate seroconversion rates (SCRs). Multiple logistic regression was used to investigate factors associated with malaria exposure. The overall malaria seroprevalence was 38.8% for PfAMA-1, 36.4% for PfMSP-119, 2.2% for PvAMA-1, and 9.3% for PvMSP-119. Between study areas, the proportion of seropositivity for any P. falciparum and P. vivax antigens was significantly highest in Pos Kuala Betis with 34.7% (p < 0.001) and 13.6% (p < 0.001), respectively. For all parasite antigens except for PvAMA-1, the proportion of seropositive individuals significantly increased with age (all p < 0.001). Based on the SCR, there was a higher level of P. falciparum transmission than P. vivax in the study area. Multivariate regression analyses showed that living in Pos Kuala Betis was associated with both P. falciparum (adjusted odds ratio [aOR] 5.6, p < 0.001) and P. vivax (aOR 2.1, p < 0.001) seropositivities. Significant associations were also found between age and seropositivity to P. falciparum and P. vivax antigens. Analysis of community-based serological data helps describe the level of transmission, heterogeneity, and factors associated with malaria exposure among indigenous communities in Peninsular Malaysia. This approach could be an important adjunct tool for malaria monitoring and surveillance in low malaria transmission settings in the country.
摘要：
疟疾在世界许多地方仍然是一个公共卫生问题。在马来西亚,自2018年以来，在国家消除疟疾计划和有效的疾病通报方面取得了重大进展，导致零土著人类疟疾病例。然而,该国仍然需要确定疟疾的暴露程度和传播方式，特别是在高危人群中。在这项研究中,血清学方法用于测量吉兰丹土著OrangAsli社区中恶性疟原虫和间日疟原虫的传播水平，马来西亚半岛。在三个OrangAsli社区进行了基于社区的横断面调查(即，PosBihai,PosGob,和PosKualaBetis)于2019年6月至7月在吉兰丹。使用两种恶性疟原虫（PfAMA-1和PfMSP-119）和两种间日疟原虫（PvAMA-1和PvMSP-119）抗原，通过酶联免疫吸附测定（ELISA）评估了对疟疾的抗体反应。使用可逆催化模型分析年龄调整的抗体应答以计算血清转化率(SCR)。采用多因素logistic回归分析与疟疾暴露相关的因素。PfAMA-1的总体疟疾血清阳性率为38.8％，PfMSP-119为36.4％，PvAMA-1为2.2％，PvMSP-119为9.3％。在研究区域之间，任何恶性疟原虫和间日疟原虫抗原的血清阳性比例在PosKualaBetis中最高，分别为34.7％（p<0.001）和13.6％（p<0.001），分别。对于除PvAMA-1外的所有寄生虫抗原，血清阳性个体的比例随年龄显着增加（所有p<0.001）。根据SCR，在研究区域，恶性疟原虫的传播水平高于间日疟原虫。多变量回归分析显示，生活在PosKualaBetis与恶性疟原虫（校正比值比[aOR]5.6，p<0.001）和间日疟原虫（aOR2.1，p<0.001）血清阳性相关。在年龄与恶性疟原虫和间日疟原虫抗原的血清阳性之间也发现了显着关联。基于社区的血清学数据分析有助于描述传播水平，异质性，以及与马来西亚半岛土著社区疟疾暴露相关的因素。这种方法可以成为该国低疟疾传播环境中疟疾监测和监测的重要辅助工具。
