Virale Hämorrhagische Septikämie (VHS) und Infektiöse Hämatopoetische Nekrose (IHN) – Viral Hemorrhagic Septicemia and Infectious Hematopoietic Necrosis

According to EU legislation and OIE definition, Viral Haemorrhagic Septicaemia (VHS) and Infectious Haematopoietic Necrosis (IHN) are notifiable diseases. These diseases are caused by the rhabdoviruses VHS virus (VHSV) and IHN virus (IHNV), respectively. The national reference laboratory for VHS and IHN at the Institute of Infectology, Friedrich-Loeffler-Institut (FLI), Federal Research Institute for Animal Health is responsible for the annual data collection and analysis from the diagnostic laboratories of all German federal states and reports the results to the European Community Reference Laboratory, located in Copenhagen, Denmark. These reports contain general information on aquaculture in Germany including structure and production as well as specific data on epidemiology based on diagnostics in the regional laboratories and the national reference laboratory. Salmonids, mainly rainbow trout (Oncorhynchus mykiss) were produced in 4,081 farms. In 2013, 12 new VHS and 5 new IHN outbreaks in trout frams were registered by TSN. Laboratory diagnosis was conducted using accredited methods such as cell cultivation followed by identification of viral pathogens using immunofluorescence, neutralization assay and/or antigen ELISA as described in CD 2001/183/EC or in the OIE recommendations. Molecular biological diagnostic methods such as RT-PCR or real-time PCR are recently under validation. Furthermore, results obtained by RT-PCR and sequencing can be used to trace the origin of the viruses from outbreaks and therefore facilitate tracking of introduction routes and countermeasures. Possible options to control VHS and IHN outbreaks are described by EU legislation.