Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2019

Erindi/veggspjald / Talk/poster V34

Source, transmission and development of Ichthyophonus hoferi infection in the Icelandic summer-spawning herring

Höfundar / Authors: Hrólfur Smári Pétursson (1) Birkir Þ. Bragason (1), Guðmundur J. Óskarsson (2) and Árni Kristmundsson (1)

Starfsvettvangur / Affiliations: 1. Institute for Experimental Pathology at Keldur, University of Iceland. Keldnavegur 3, IS-112, Reykjavik Iceland hrolfurs@hi.is; birkirbr@hi.is; arnik@hi.is 2. Marine and Freshwater Research Institute in Iceland, Skúlagata 4, IS-101 Reykjavík, Iceland. gudmundur.j.oskarsson@hafogvatn.is

Kynnir / Presenter: Hrólfur Smári Pétursson

In 2008, severe and highly prevalent (up to 70-80%) Ichthyophonus hoferi infections were experienced in older cohorts of herring, followed by a significant decline in the stock. The reason for this sudden increase in infections of this endemic pathogen is unclear and a decade later, the epidemic is still ongoing. The aim is to investigate the source, transmission and development of Ichthyophonus infections to shed light on this prolonged epidemic in the Icelandic population of summer spawning herring. Different age groups of herring and various species of pelagic crustaceans, as well as haddock, cod and plaice are examined for infections using PCR, qPCR, conventional histology and in situ hybridization.
Results indicate that various pelagic crustacean species carry Ichthyophonus infections and are therefore a reservoir for the parasite. Factors such as consumption of infected crustaceans over extended periods and/or the stressful process of maturation may lead to intensified infections and development of clinical disease. Changes in environment cannot be disregarded but data is lacking for further support. The route of transmission and the development of the parasite in fish and crustacean hosts, remain unclear. Observations via in situ hybridization technique and calcofluor-white chitin staining further support infection via crustacean consumption.