TABLE 1.

Tissue distribution of plaque variants

Tissue source of isolate	% of isolatea
	Large-plaque virus	Small-plaque virus
Brain	0.5	99.5
GI tract	99.5	0.5
Lung	99	1
CSF	47	53
Kidney	22	78

^aPlaques were examined 72 h p.i. Sample size was 200 plaques.