Update July 2nd 2019
In June we reported that a small number of fish exhibiting signs of bleeding and/or ulceration had been caught in Norway, Ireland and Scotland. This post provides an update on the current knowledge relating to the disease in the British Isles.
Firstly, a number of fish health vets and ecologists in Norway and Sweden have suggested a link to a vitamin deficiency – vitamin B1, otherwise known as thiamine. No causative pathogen, such as a bacteria or a virus, has been reported to date. The link with B1 came about as fish that were treated with vitamin B1 fully recovered and those not treated had increased mortality. Over recent years the issue of vitamin B1 deficiency has been recorded in other fish species, birds and shell fish. There is also the possibility that the thiamine treatment may have boosted the affected salmon’s immune system and aided with recovery.
In the UK no causative agent has been found for the fish showing signs of this trauma. However, the testing is ongoing and results are still awaited. In the meantime, the various Fish Health Inspectors around the British Isles are continuing to monitor the situation. It remains the case that it is important that any moribund (dying) fish are screened for pathogens by an appropriate authority, and to do this they must, where possible, be kept alive until a Fish Health Inspector can examine them. Unfortunately, dead fish cannot provide the information needed to inform people of what is going on. If the fish is not moribund but still exhibiting signs of bleeding or ulceration, or you are unsure, then please just take a photo and contact the relevant authority detailed below. However, at the moment there is no requirement at this stage to remove fish with damage for disease control purposes.
The contact details for the various Fish Health Inspectors and organisations, along with further information are:
Ireland – Marine Institute (Fish Health) www.marine.ie/Home/site-area/areas-activity/fish-health/fish-health. Tel (+) 353 (0)91387200
Scotland – Marine Scotland Fish Health Inspectorate, https://www2.gov.scot/Topics/marine/Fish-Shellfish/FHI/Personnel. Tel 0131 244 3498
England and Wales – National Fish Laboratory. Email fish.health@environment-agency.gov.uk Tel 0148041458
Northern Ireland – DAERA Northern Ireland, www.daera-ni.gov.uk/articles/northern-ireland-disease-status-and-designations-notices. Tel 02844 618090