Table 2. Bioassay of disinfected 263K brain homogenate in tg7 mice.

Disinfectant (fresh)	Dilution of 263K scrapie brain homogenate inoculated after treatmenta							Titerb	Log10 Reduction in titer
	10−3	10−4	10−5	10−6	10−7	10−8	10−9
Saline	4/4 c, 55	4/4, 62	4/4, 66	4/4, 71	4/4, 81.5	1/4, 258	1/4, 146	9.5	NA
40% Wex-cide	nt	0/5	0/4	0/4	nt	nt	nt	≤ 5.0	≥4.5
4% Wex-cide	0/6	0/3	0/4	0/3	nt	nt	nt	≤ 4.0	≥5.5
2% eLpH	1/4, 197	0/4	0/4	nt	nt	nt	nt	4.25	5.25
Disinfectant (aged)
4% Wex-cide 6 weeks	0/8, 288	0/6	0/5	nt	nt	nt	nt	≤ 4.0	≥5.5
2% eLpH 6 weeks	0/8, 288	0/7	0/6	nt	nt	nt	nt	≤ 4.0	≥5.5
4% Wex-cide 8 months	0/8, 299	0/6	0/7	nt	nt	nt	nt	≤ 4.0	≥5.5
2% eLpH 8 months	0/8, 299	0/9	0/5	nt	nt	nt	nt	≤ 4.0	≥5.5

^aAliquots of 263K brain homogenates (10%) were exposed to different disinfectants or saline for 30 minutes at a 1:9 ratio. Solutions were then further diluted for bioassay in mice. Each recipient mouse received 30μl of inoculum.

^b The calculated titer reported is the log₁₀LD₅₀/gram of tissue

^c The numerator is the number of prion-positive mice (see Methods), and the denominator is the number of mice inoculated. For groups with positive mice the average incubation period in days-post inoculation (dpi) is provided. Tg7 mice typically do not develop 263K prion disease after 200 dpi. Mice that did not develop clinical signs of prion disease were euthanized at 288–300 dpi.

NA: not applicable, nt: not tested