Koi Herpesvirus of the family Herpesviridae

Koi Herpesvirus Disease is a viral disease of common carp Cyprinus carpio, including all its ornamental varieties such as koi, ghost koi etc. The virus is highly contagious and may cause up to 100% mortality. KHV has already caused severe fish losses to ornamental wholesalers, retailers and carp fishery owners and continues to pose a significant threat to anyone dealing with or keeping common carp.

As a notifiable disease there is a legal obligation to report any suspicion of a clinical outbreak of Koi Herpesvirus Disease to the Fish Health Inspectorate (FHI). If the disease is found to be present the FHI will advise on the most appropriate methods of control.

 

Koi Herpes Virus Disease  (FHI)

Viral haemorrhagic septicaemia virus (VHSV)

Viral Haemorrhagic Septicaemia Virus (VHSV) is an important fish virus that has caused several large-scale fish kills in both fresh and saltwater fish in farmed and wild fish. Viral haemorrhagic septicaemia (VHS) is a highly infectious virus disease predominantly affecting rainbow trout (Oncorhynchus mykiss) in aquaculture.

The virus is an enveloped negative-stranded RNA virus belonging to the family Rhabdoviridae and the genus Novirhabdovirus. The virus can be divided into 4 distinct genotypes and 10 subtypes with different geographical occurrence, host range and infectivity patterns. VHSV have been isolated in the tempered Northern hemisphere, e.g. North America, Asia and Europe. The disease occurs endemically in the continental part of Europe, in Turkeyand in part of Finland. Occasionally outbreaks in farmed rainbow trout and turbot have occurred in Scandinavia and the British Isles. The North Sea, Kattegat and the Baltic Seahouses endemically infected populations of wild fish. VHSV have been isolated from more than 82 different fish species.

 Viral Haemorrhagic septicaemia virus (OIE)

Infectious haematopoietic necrosis virus(IHNV)

Infectious haematopoietic necrosis (IHN) is a viral disease affecting most species of salmonid fish. Caused by the rhabdovirus, infectious haematopoietic necrosis virus (IHNV), the principal clinical and economic consequences of IHN occur on farms rearing fry or juvenile rainbow trout in freshwater where acute outbreaks can result in very high mortality. However, both Pacific and Atlantic salmon reared in fresh water or sea water can be severely affected.

Infectious hematopoietic necrosis virus (IHNV), is a negative-sense single-stranded RNA virus that is a member of the familyRhabdoviridaeand the genusNovirhabdovirus,like VHSV. IHNV is present inUSAandCanada, inJapanandKoreaand in the continental part ofEurope.

Both VHS and IHN are listed as non-exotic diseases in the EU and are therefore watched closely by the European Community Reference Laboratory for Fish Diseases, and by National Reference Laboratories.