TABLE 1.

Survival of vegetative C. difficile on nutrient-free agar^a

Time (h:min)	ATCC 9689b		VA 11		VA 17		CC 20
	Aerobicc	Anaerobicd	Aerobic	Anaerobic	Aerobic	Anaerobic	Aerobic	Anaerobic
0	4+	4+	4+	4+	4+	4+	4+	4+
0:15	4+	4+	4+	4+	4+	4+	4+	4+
0:30	4+	4+	4+	4+	4+	4+	3+	4+
1:00	3+	4+	4+	4+	4+	4+	2+	4+
2:00	4+	4+	4+	4+	4+	4+	3+	4+
3:00	2+	4+	4+	4+	3+	4+	1+	4+
6:00		4+	1+	4+	1+	4+		4+
9:00		4+		4+		4+		4+

^a1+, fewer than 30 scattered colonies; 2+, 30 to 100 scattered colonies, few touching; 3+, >100 crowded but distinct colonies; 4+, lawn.

^bStrain of C. difficile.

^cRoom air at ambient temperature.

^dAnaerobic chamber at 37°C.