Abstract:
The increase in incidence and geographical expansion of viruses transmitted by the Aedes mosquitoes, such as dengue (DENV) and zika (ZIKV) in the Americas, represents a burden for healthcare systems in tropical and subtropical regions. These and other under-detected arboviruses co-circulate in Costa Rica, adding additional complexity to their management due to their shared epidemiological behavior and similarity of symptoms in early stages. Since diagnostics of febrile illness is mostly based on clinical symptoms alone, we gathered acute-phase serum and urine from 399 samples of acute dengue-like cases from two healthcare facilities of Costa Rica, during an outbreak of arboviruses from July 2017 to May 2018, and tested them using molecular and serological methods. The analyses showed that of the clinically presumptive arbovirus cases that were reported, only 39.4% (n=153) of the samples were confirmed positive by RT-PCR to be DENV (DENV (10.3%), CHIKV (0.2%), ZIKV (27.3%), or mixed infections (1.5%). RT-PCR for other alphaviruses and flaviviruses, and PCR for Leptospira sp were negative. Furthermore, to assess flavivirus positivity in post-acute patients, the negative sera were tested against Dengue-IgM. 20% of sera were found positive, confounding even more the definitive number of cases, and emphasizing the need of several distinct diagnostic tools for accurate diagnostics. Molecular characterization of the prM and E genes from isolated viruses revealed that the American/Asian genotype of DENV-2 and the Asian lineage of ZIKV were circulating during this outbreak. Two different clades of DENV-2 American/Asian genotype were identified to co-circulate in the same region and a difference in the platelet and leukocyte count was noted between people infected with each clade, suggesting a putative distinct virulence. Our study sheds light on the necessity for healthcare strategies in managing arbovirus outbreaks, emphasizing the importance of comprehensive molecular and serological diagnostic approaches, as well as molecular characterization. This approach aids in enhancing our understanding of the clinical and epidemiological aspects of arboviral diseases during outbreaks. Our research highlights the need to strengthen training programs for health professionals and the need to increase research-based on laboratory evidence for diagnostic accuracy, guidance, development and implementation of public health interventions and epidemiological surveillance.
摘要:
伊蚊传播的病毒的发病率增加和地域扩展,例如美洲的登革热(DENV)和寨卡(ZIKV),代表了热带和亚热带地区医疗保健系统的负担。这些和其他未被检测到的虫媒病毒在哥斯达黎加共同传播,由于他们共同的流行病学行为和早期症状的相似性,增加了他们管理的额外复杂性。由于发热性疾病的诊断主要基于临床症状,我们收集了来自哥斯达黎加两个医疗机构的399例急性登革热样病例的急性期血清和尿液,在2017年7月至2018年5月的一次虫媒病毒暴发期间,并使用分子和血清学方法对其进行了测试。分析显示,在报告的临床推定虫媒病毒病例中,只有39.4%(n=153)的样本通过RT-PCR证实为DENV(DENV(10.3%),CHIKV(0.2%),ZIKV(27.3%),或混合感染(1.5%)。其他甲病毒和黄病毒的RT-PCR,钩端螺旋体的PCR为阴性。此外,评估急性后患者的黄病毒阳性,对阴性血清进行了登革热IgM检测。20%的血清为阳性,甚至混淆了案件的确定数量,并强调需要几种不同的诊断工具来进行准确的诊断。来自分离病毒的prM和E基因的分子表征表明,在这次爆发期间,DENV-2的美国/亚洲基因型和ZIKV的亚洲谱系正在流行。DENV-2美国/亚洲基因型的两个不同的进化枝被确定为在同一区域共同循环,并且在感染每个进化枝的人之间注意到血小板和白细胞计数的差异,暗示了一种推测的独特毒力.我们的研究揭示了医疗保健策略在管理虫媒病毒爆发中的必要性,强调全面的分子和血清学诊断方法的重要性,以及分子表征。这种方法有助于增强我们对暴发期间虫媒病毒病的临床和流行病学方面的理解。我们的研究强调需要加强对卫生专业人员的培训计划,并需要增加基于实验室证据的诊断准确性研究,指导,制定和实施公共卫生干预措施和流行病学监测。