Pathology. A) Rainbow trout from the co-habitation group (KV) collected 12 days after challenge. Note the loss of scales and epidermis (arrow) and haemorrhages on the vicera. This individual was positive (kidney; Ct = 26) for presence of VHS virus. B) Rainbow trout from the bath challenged group (BV) collected 7 days after challenge showing haemorrhages (arrows) in the somatic muscle (kidney, VHSV Ct = 27). C) Loss of haematopoietic cells and massive haemorrhages in the kidney of a rainbow trout (KV group) collected 18 days after challenge (kidney; VHSV Ct = 36, spleen; VHSV Ct = 28), D) Accumulation of inflammatory cells (arrow) surrounding a blood sinus in the liver of rainbow trout (group BV) collected 19 days after challenge (kidney, VHSV Ct = 24).