TABLE 1.

Comparison of the efficiencies of plaque formation (e.o.p.) at the NPT of 38.5°C or 39.5°C and the PT of 32°C^a

Virus	Efficiency of plaque formation at NPT indicated and PT of 32°C
	38.5°C	39.5°C	39.5°C
ts1249	8.5 × 10−5	1.0 × 10−4
ts+1249rev	1.1	0.9
ts+1249MR	1.5	1.1
ts1204	2.4 × 10−5	<1.2 × 10−5
ts+1204rev	1.1	3.0 × 10−2a
Strain 17 wt	1.6	1.2
ts1208			4.3 × 10−4
ts+1208MR			0.9
Strain 17 wt			0.5

^aPlaques were very small compared with wt HSV-1 plaques at 39.5°C.