Munang'andu Hetron M
Section of Aquatic Medicine and Nutrition, Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences Oslo, Norway.
Front Microbiol. 2016 Dec 14;7:1986. doi: 10.3389/fmicb.2016.01986. eCollection 2016.
Studies on the epidemiology of viral diseases in aquaculture have for a long time depended on isolation of viruses from infected aquatic organisms. The role of aquatic environments in the epidemiology of viral diseases in aquaculture has not been extensively expounded mainly because of the lack of appropriate tools for environmental studies on aquatic viruses. However, the upcoming of metagenomics analyses opens great avenues in which environmental samples can be used to study the epidemiology of viral diseases outside their host species. Hence, in this review I have shown that epidemiological factors that influence the composition of viruses in different aquatic environments include ecological factors, anthropogenic activities and stocking densities of cultured organisms based on environmental metagenomics studies carried out this far. Ballast water transportation and global trade of aquatic organisms are the most common virus dispersal process identified this far. In terms of disease control for outdoor aquaculture systems, baseline data on viruses found in different environments intended for aquaculture use can be obtained to enable the design of effective disease control strategies. And as such, high-risk areas having a high specter of pathogenic viruses can be identified as an early warning system. As for the control of viral diseases for indoor recirculation aquaculture systems (RAS), the most effective disinfection methods able to eliminate pathogenic viruses from water used in RAS can be identified. Overall, the synopsis I have put forth in this review shows that environmental samples can be used to study the epidemiology of viral diseases in aquaculture using viral metagenomics analysis as an overture for the design of rational disease control strategies.
长期以来，水产养殖中病毒性疾病的流行病学研究一直依赖于从受感染的水生生物中分离病毒。水生环境在水产养殖病毒性疾病流行病学中的作用尚未得到广泛阐述，主要是因为缺乏用于水生病毒环境研究的合适工具。然而，宏基因组学分析的出现开辟了广阔的途径，可利用环境样本研究宿主物种之外的病毒性疾病流行病学。因此，在本综述中，基于迄今为止开展的环境宏基因组学研究，我指出影响不同水生环境中病毒组成的流行病学因素包括生态因素、人为活动以及养殖生物的放养密度。压载水运输和水生生物的全球贸易是迄今为止确定的最常见的病毒传播过程。就室外水产养殖系统的疾病控制而言，可获取不同水产养殖用水环境中病毒的基线数据，以设计有效的疾病控制策略。这样一来，具有高致病性病毒风险的高风险区域可被识别出来作为预警系统。至于室内循环水养殖系统（RAS）的病毒性疾病控制，可确定能够从RAS用水中消除致病性病毒的最有效消毒方法。总体而言，我在本综述中提出的概要表明，利用病毒宏基因组学分析作为合理疾病控制策略设计的序曲，环境样本可用于研究水产养殖中病毒性疾病的流行病学。
