TABLE 2.

Pathogenicity scores in C3H mice

Pathogenicity	TTJ inflammation	EPB culture	No. of organs colonized
Nonpathogenic	−	−	0
Low pathogenicitya	+/−	+/−	0 or 1b
Pathogenic	+	+	1–6

^aAt least one of the three must be positive. 

^bBladder.