Table 1.

Facilities, primary function, number of rooms surveyed, and dirty-bedding exposure time for surveillance mice monitored for EHS prevalence in 2009

Facility	Primary function	No. of rooms	Exposure time (mo)
A	Barrier and experimental use	14	1.5–6
B	Semibarrier and experimental use	5	1–5.5
C	Breeding and experimental use	19	0.6–5
D	Breeding and experimental use	14	1.5–6
E	Experimental use	3	1.5–6.5
F	Experimental use	2	3–5.5