Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Malaysia.
United States Naval Medical Research Unit-2, Singapore.
PLoS Negl Trop Dis. 2021 May 20;15(5):e0009445. doi: 10.1371/journal.pntd.0009445. eCollection 2021 May.
Dengue fever is the most common mosquito-borne infection worldwide where an expanding surveillance and characterization of this infection are needed to better inform the healthcare system. In this surveillance-based study, we explored the prevalence and distinguishing features of dengue fever amongst febrile patients in a large community-based health facility in southern peninsular Malaysia.
Over six months in 2018, we recruited 368 adults who met the WHO 2009 criteria for probable dengue infection. They underwent the following blood tests: full blood count, dengue virus (DENV) rapid diagnostic test (RDT), ELISA (dengue IgM and IgG), nested RT-PCR for dengue, multiplex qRT-PCR for Zika, Chikungunya and dengue as well as PCR tests for Leptopspira spp., Japanese encephalitis and West Nile virus.
Laboratory-confirmed dengue infections (defined by positive tests in NS1, IgM, high-titre IgG or nested RT-PCR) were found in 167 (45.4%) patients. Of these 167 dengue patients, only 104 (62.3%) were positive on rapid diagnostic testing. Dengue infection was significantly associated with the following features: family or neighbours with dengue in the past week (AOR: 3.59, 95% CI:2.14-6.00, p<0.001), cutaneous rash (AOR: 3.58, 95% CI:1.77-7.23, p<0.001), increased temperature (AOR: 1.33, 95% CI:1.04-1.70, p = 0.021), leucopenia (white cell count < 4,000/μL) (AOR: 3.44, 95% CI:1.72-6.89, p<0.001) and thrombocytopenia (platelet count <150,000/μL)(AOR: 4.63, 95% CI:2.33-9.21, p<0.001). Dengue infection was negatively associated with runny nose (AOR: 0.47, 95% CI:0.29-0.78, p = 0.003) and arthralgia (AOR: 0.42, 95% CI:0.24-0.75, p = 0.004). Serotyping by nested RT-PCR revealed mostly mono-infections with DENV-2 (n = 64), DENV-1 (n = 32) and DENV-3 (n = 17); 14 co-infections occurred with DENV-1/DENV-2 (n = 13) and DENV-1/DENV-4 (n = 1). Besides dengue, none of the pathogens above were found in patients' serum.
Acute undifferentiated febrile infections are a diagnostic challenge for community-based clinicians. Rapid diagnostic tests are increasingly used to diagnose dengue infection but negative tests should be interpreted with caution as they fail to detect a considerable proportion of dengue infection. Certain clinical features and haematological parameters are important in the clinical diagnosis of dengue infection.
登革热是全球最常见的蚊媒传染病，需要扩大对这种感染的监测和特征描述，以便更好地为医疗保健系统提供信息。在这项基于监测的研究中，我们在马来西亚半岛南部的一个大型社区卫生机构中探索了发热患者中登革热的流行情况和特征。
在 2018 年的六个月中，我们招募了符合世界卫生组织 2009 年可能登革热感染标准的 368 名成年人。他们接受了以下血液检查：全血细胞计数、登革热病毒（DENV）快速诊断试验（RDT）、酶联免疫吸附试验（dengue IgM 和 IgG）、巢式 RT-PCR 检测登革热、多重 qRT-PCR 检测寨卡、基孔肯雅热和登革热以及用于检测莱姆螺旋体 spp.、日本脑炎和西尼罗河病毒的 PCR 检测。
实验室确诊的登革热感染（定义为 NS1、IgM、高滴度 IgG 或巢式 RT-PCR 阳性）在 167 名（45.4%）患者中发现。在这 167 名登革热患者中，只有 104 名（62.3%）快速诊断检测呈阳性。登革热感染与以下特征显著相关：过去一周家中或邻居有登革热患者（优势比：3.59，95%置信区间：2.14-6.00，p<0.001）、皮肤疹（优势比：3.58，95%置信区间：1.77-7.23，p<0.001）、体温升高（优势比：1.33，95%置信区间：1.04-1.70，p=0.021）、白细胞减少症（白细胞计数<4000/μL）（优势比：3.44，95%置信区间：1.72-6.89，p<0.001）和血小板减少症（血小板计数<150000/μL）（优势比：4.63，95%置信区间：2.33-9.21，p<0.001）。登革热感染与流鼻涕（优势比：0.47，95%置信区间：0.29-0.78，p=0.003）和关节痛（优势比：0.42，95%置信区间：0.24-0.75，p=0.004）呈负相关。巢式 RT-PCR 血清分型显示主要为单感染，包括 DENV-2（n=64）、DENV-1（n=32）和 DENV-3（n=17）；14 例合并感染，包括 DENV-1/DENV-2（n=13）和 DENV-1/DENV-4（n=1）。除登革热外，患者血清中未发现上述任何病原体。
急性未分化发热感染对社区临床医生来说是一个诊断挑战。快速诊断检测越来越多地用于诊断登革热感染，但阴性检测应谨慎解读，因为它们未能检测到相当比例的登革热感染。某些临床特征和血液学参数对登革热感染的临床诊断很重要。
