Table 2.

Survival of infectious hematopoietic necrosis virus in fish tissues

Species	Tissue	Source of virus contamination	Test conditions (°C)	Starting titre	Titre reduction (log10)/virus detection	Reference
Rainbow trout	Homogenate of kidney, spleen and heart	7–9 cm fish from a farm with a recent history of IHN	4	104.8 TCID50 mL−1	Titre reduced by about 1–2 log per day. Virus survived 3 (but not 4) days	[134]
			25		No evidence of virus after 1 day
Rainbow trout	Homogenate of muscle and skin from fingerlings (fish minus heads tails and viscera)	Seeded with IHNV	4	105.7 TCID50 mL−1	Titre reduced by 3 logs after 7 days	[140]
			10		Titre reduced by 4 logs after 5 days
			21		Titre reduced by 3 logs after 4 days
Rainbow trout	Individual homogenates of brain, liver, kidney and spleen from 3 fish of approx 900 g	Seeded with IHNV	−20	103.6–103.9 pfu mL−1	Virus survived for 5 months in brain, 3.5 months in liver and spleen and 4 weeks in kidney tissue	[150]
			4		Virus survived at least 5 weeks in brain, 4 weeks in liver, 3 weeks in spleen and was detected after 3 but not 7 days in kidney tissue
			20		Virus survived at least 1 week in brain, losing 1 log titre; survived 1 day in liver or spleen. Virus detected intermittently over a 3 day period in kidney, but not after 1 week
Sockeye salmon	Fry	Seeded with IHNV	−20	103.7 pfu mL−1	Virus survived 4 weeks	[150]
			4		Detected after 3 but not 4 weeks
			20		Detected after 4 h but not 24 h
Sockeye salmon	Homogenate of gut, pyloric ceca, kidney, spleen and liver	Seeded with IHNV	38	>107 pfu mL−1	c. 5 logs in <50 min	[141]
			32		c. 4 logs in 2.5 h
			28		c. 4 logs in 2.5 h
			8		No significant loss after c 3 h