Hacettepe University, Faculty of Sciences, Department of Biology, Division of Ecology, Ankara, Turkey.
Robert Koch Institute, Center for Biological Threats and Special Pathogens 1 (ZBS-1), Berlin, Germany.
Infect Genet Evol. 2018 Jan;57:36-45. doi: 10.1016/j.meegid.2017.11.003. Epub 2017 Nov 8.
Mosquitoes are involved in the transmission and maintenance of several viral diseases with significant health impact. Biosurveillance efforts have also revealed insect-specific viruses, observed to cocirculate with pathogenic strains. This report describes the findings of flavivirus and rhabdovirus screening, performed in eastern Thrace and Aegean region of Anatolia during 2016, including and expanding on locations with previously-documented virus activity. A mosquito cohort of 1545 individuals comprising 14 species were collected and screened in 108 pools via generic and specific amplification and direct metagenomics by next generation sequencing. Seven mosquito pools (6.4%) were positive in the flavivirus screening. West Nile virus lineage 1 clade 1a sequences were characterized in a pool Culex pipiens sensu lato specimens, providing the initial virus detection in Aegean region following 2010 outbreak. In an Anopheles maculipennis sensu lato pool, sequences closely-related to Anopheles flaviviruses were obtained, with similarities to several African and Australian strains of this new insect-specific flavivirus clade. In pools comprising Uranotaenia unguiculata (n=3), Cx. pipiens s.l. (n=1) and Aedes caspius (n=1) mosquitoes, sequences of a novel flavivirus, distantly-related to Flavivirus AV2011, identified previously in Spain and Turkey, were characterized. Moreover, DNA forms of the novel flavivirus were detected in two Ur. unguiculata pools. These sequences were highly-similar to the sequences amplified from viral RNA, with undisrupted reading frames, suggest the occurrence of viral DNA forms in natural conditions within mosquito hosts. Rhabdovirus screening revealed sequences of a recently-described novel virus, named the Merida-like virus Turkey (MERDLVT) in 5 Cx. pipiens s.l. pools (4.6%). Partial L and N gene sequences of MERDLVT were well-conserved among strains, with evidence for geographical clustering in phylogenetic analyses. Metagenomics provided the near-full genomic sequence in a specimen, revealing an identical genome organization and limited divergence from the prototype MERDLVT isolate.
蚊子在几种具有重大健康影响的病毒性疾病的传播和维持中发挥作用。生物监测工作还发现了昆虫特异性病毒，这些病毒与致病性菌株同时存在。本报告描述了在 2016 年东色雷斯和安纳托利亚爱琴海地区进行的黄病毒和弹状病毒筛查结果，包括并扩展了以前有病毒活动的地点。通过通用和特定扩增以及下一代测序的直接宏基因组学，从 14 种 1545 只蚊子中收集和筛查了 108 个虫池。在黄病毒筛查中，有 7 个蚊子池（6.4%）呈阳性。在库蚊属蚊子中鉴定出西尼罗河病毒谱系 1 分支 1a 序列，这是继 2010 年爆发后在爱琴海地区首次检测到该病毒。在一个按蚊属蚊子池中，获得了与按蚊属黄病毒密切相关的序列，与该新型昆虫特异性黄病毒分支的几个非洲和澳大利亚株具有相似性。在包含 U. unguiculata（n=3）、Cx. pipiens s.l.（n=1）和 Aedes caspius（n=1）蚊子的 3 个虫池中，鉴定出一种新型黄病毒的序列，该病毒与先前在西班牙和土耳其发现的 Flavivirus AV2011 远相关。此外，在 2 个 U. unguiculata 虫池中检测到新型黄病毒的 DNA 形式。这些序列与从病毒 RNA 扩增的序列高度相似，具有完整的阅读框，表明在蚊子宿主的自然条件下存在病毒 DNA 形式。弹状病毒筛查显示，在 5 个 Cx. pipiens s.l. 虫池中发现了一种新型病毒的序列，称为 Merida-like virus Turkey（MERDLVT）（4.6%）。MERDLVT 的 L 和 N 基因部分序列在菌株间高度保守，系统发育分析表明存在地理聚类证据。宏基因组学在一个标本中提供了近乎完整的基因组序列，揭示了与原型 MERDLVT 分离株相同的基因组组织和有限的差异。
