Bookelaar B E, O'Reilly A J, Lynch S A, Culloty S C
Aquaculture and Fisheries Development Centre, School of Biological, Earth and Environmental Sciences & Environmental Research Institute, University College Cork, Cork, Ireland.
Dis Aquat Organ. 2018 Sep 27;130(3):221-233. doi: 10.3354/dao03264.
Ostreid herpesvirus-1 microVar (OsHV-1 µVar) has been responsible for significant mortalities globally in the Pacific oyster Crassostrea gigas. While the impact of this virus on the Pacific oyster has been significant, this pathogen may have wider ecosystem consequences. It has not been definitively determined how the virus is sustaining itself in the marine environment and whether other species are susceptible. The shore crab Carcinus maenas is a mobile predator and scavenger of C. gigas, commonly found at Pacific oyster culture sites. The aim of this study was to investigate the role of the crab in viral maintenance and transmission to the Pacific oyster. A field trial took place over 1 summer at different shore heights at 2 Irish Pacific oyster culture sites that are endemic for OsHV-1 µVar. Infection of OsHV-1 µVar in tissues of C. maenas at both shore heights of both sites was detected by polymerase chain reaction (PCR), quantitative PCR (qPCR), in situ hybridization and direct Sanger sequencing. In addition, a laboratory trial demonstrated that transmission of the virus could occur to naïve C. gigas within 4 d, from C. maenas previously exposed to the virus in the wild. These findings provide some insight into the possibility that the virus can be transmitted through marine food webs. The results also suggest viral plasticity in the hosts required by the virus and potential impacts on a range of crustacean species with wider ecosystem impacts if transmission to other species occurs.
牡蛎疱疹病毒-1微变种（OsHV-1 µVar）已在全球范围内导致太平洋牡蛎巨蛎大量死亡。虽然这种病毒对太平洋牡蛎的影响巨大，但这种病原体可能会对生态系统产生更广泛的影响。目前尚未明确确定该病毒如何在海洋环境中维持自身生存，以及其他物种是否易感。海滨蟹平背蜞是巨蛎的一种移动性捕食者和清道夫，常见于太平洋牡蛎养殖场所。本研究的目的是调查这种螃蟹在病毒维持以及向太平洋牡蛎传播过程中所起的作用。在爱尔兰两个太平洋牡蛎养殖场所（均为OsHV-1 µVar地方病流行区）的不同海岸高度进行了为期1个夏季的田间试验。通过聚合酶链反应（PCR）、定量PCR（qPCR）、原位杂交和直接桑格测序，在两个场所不同海岸高度的平背蜞组织中均检测到了OsHV-1 µVar感染。此外，一项实验室试验表明，在野外曾接触过该病毒的平背蜞可在4天内将病毒传播给未接触过病毒的太平洋牡蛎。这些发现为该病毒可通过海洋食物网传播的可能性提供了一些见解。研究结果还表明该病毒对宿主具有可塑性，如果病毒传播到其他物种，可能会对一系列甲壳类物种产生潜在影响，并对生态系统产生更广泛的影响。
