Table 1. Primary and secondary transmissions of Nor98 agent to PrP^VRQ transgenic mice.

Isolate (PrP genotype)	Passage number	Brain tissue*	Mean survival time, days (SEM)	n/n′†
Lindås (AHQ)	First	2 mg	295 (18)	7/7
	Second	2 mg	235 (6)	7/7
	Third	2 mg	190 (10)	6/6
	Fourth	0.2 mg	222 (6)	5/5
Rauland (ARQ)	First	2 mg	224 (10)	6/6
	Second	2 mg	202 (7)	7/7
	Second	200 ng	251 (8)	6/6
	Second	20 ng	294 (17)	6/6
	Second	2 ng	329 (14)	6/6‡

^*Animals were inoculated intracerebrally with the indicated amount of brain tissue equivalent

^†Diseased/inoculated

^‡All six mice tested PrP^res-positive by immunoblotting