Huang Fang, Takala-Harrison Shannon, Liu Hui, Xu Jian-Wei, Yang Heng-Lin, Adams Matthew, Shrestha Biraj, Mbambo Gillian, Rybock Demian, Zhou Shui-Sen, Xia Zhi-Gui, Zhou Xiao-Nong, Plowe Christopher V, Nyunt Myaing M
Division of Malaria Research, Institute for Global Health, University of Maryland School of Medicine, Baltimore, Maryland.
National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China.
Am J Trop Med Hyg. 2017 Nov;97(5):1524-1531. doi: 10.4269/ajtmh.17-0167. Epub 2017 Oct 10.
Malaria infections may be symptomatic, leading to treatment, or "asymptomatic," typically detected through active surveillance, and not leading to treatment. Malaria elimination may require purging both types of infection. Using detection methods with different sensitivities, we conducted a cross-sectional study in two rural communities located along the border between China's Yunnan Province and Myanmar's Shan and Kachin States, to estimate the prevalence of asymptomatic and symptomatic malaria. In Mong Pawk, all infections detected were asymptomatic, and the prevalence of was 0.3%, 4.3%, 4.0%, and 7.8% by light microscopy, rapid diagnostic test (RDT), conventional polymerase chain reaction (cPCR), and multiplexed real-time PCR (RT-PCR), respectively, and prevalence was 0% by all detection methods. In Laiza, of 385 asymptomatic participants, 2.3%, 4.4%, and 12.2% were positive for by microscopy, cPCR, and RT-PCR, respectively, and 2.3% were -positive only by RT-PCR. Of 34 symptomatic participants in Laiza, 32.4% were positive by all detection methods. Factors associated with infection included gender (males higher than females, = 0.014), and young age group (5-17 age group compared with others, = 0.0024). Although the sensitivity of microscopy was adequate to detect symptomatic infections, it missed the vast majority (86.5%) of asymptomatic infections. Although molecular detection methods had no advantage over standard microscopy or RDT diagnosis for clinically apparent infections, malaria elimination along the Myanmar-China border will likely require highly sensitive surveillance tools to identify asymptomatic infections and guide targeted screen-and-treat interventions.
疟疾感染可能有症状，从而导致接受治疗，也可能“无症状”，通常通过主动监测发现，且不会导致接受治疗。消除疟疾可能需要清除这两种类型的感染。我们使用具有不同灵敏度的检测方法，在中国云南省与缅甸掸邦和克钦邦边境沿线的两个农村社区开展了一项横断面研究，以估算无症状和有症状疟疾的流行率。在孟帕，检测到的所有感染均为无症状感染，通过光学显微镜、快速诊断检测（RDT）、传统聚合酶链反应（cPCR）和多重实时聚合酶链反应（RT-PCR）检测的流行率分别为0.3%、4.3%、4.0%和7.8%，所有检测方法检测到的 流行率均为0%。在赖扎，385名无症状参与者中，通过显微镜检查、cPCR和RT-PCR检测，分别有2.3%、4.4%和12.2%的 呈阳性，仅通过RT-PCR检测有2.3%的 呈阳性。在赖扎的34名有症状参与者中，所有检测方法检测到的阳性率为32.4%。与感染相关的因素包括性别（男性高于女性，P = 0.014）和年轻年龄组（5 - 17岁年龄组与其他年龄组相比，P = 0.0024）。虽然显微镜检查的灵敏度足以检测有症状感染，但它遗漏了绝大多数（86.5%）无症状感染。尽管分子检测方法在临床明显感染的诊断方面相对于标准显微镜检查或RDT诊断没有优势，但中缅边境地区消除疟疾可能需要高度灵敏的监测工具来识别无症状感染并指导有针对性的筛查和治疗干预措施。
