TABLE 1.

Results of the viability study of C. burnetii in dust using BALB/c and cultivation in Vero cell lines

Collection date (no. of months since last parturition)	BALB/c mouse inoculation			Spleen wt/body wt	Culture in cell lines (Vero E6) (GE/ml)					Viable C. burnetii
	No. of GEa injected	Days p.i.b	No. of GE in spleen		Inoculated	Day 6 p.i.	1st passage	2nd passage	3rd passage
February (0)	87.5 × 103	7	66.7 × 103	0.0032	8.8 × 102	0.0	0.0	0.0	0.0	No
		7	93.2 × 103	0.0040	0.0	0.0				No
		21	80.9 × 103	0.0040	4.9 × 103	5.0 × 103	4.5 × 104	2.7 × 105	2.9 × 105	Yes
		21	79.3 × 104	0.0054	3.6 × 104	1.2 ×105	2.3 × 105	1.7 × 105	4.7 × 105	Yes
June (2)	100 × 103	7	0.0	0.0037	NDc	NAd	NA	NA	NA	No
		7	0.0	0.0039	ND	NA	NA	NA	NA	No
		21	0.0	0.0045	ND	NA	NA	NA	NA	No
		21	0.0	0.0043	ND	NA	NA	NA	NA	No
July (3)	100 × 103	7	0.0	0.0046	ND	NA	NA	NA	NA	No
		7	0.0	0.0041	ND	NA	NA	NA	NA	No
		21	0.0	0.0049	ND	NA	NA	NA	NA	No
		21	0.0	0.0041	ND	NA	NA	NA	NA	No
August (4)	100 × 103	7	0.0	0.0041	ND	NA	NA	NA	NA	No
		7	0.0	0.0042	ND	NA	NA	NA	NA	No
		21	0.0	0.0044	ND	NA	NA	NA	NA	No
		21	0.0	0.0046	ND	NA	NA	NA	NA	No
Negative control (PBS)	NA	7	0.0	0.0038	0.0	0.0	0.0	0.0	0.0	No
		7	0.0	0.0033	0.0	0.0	0.0	0.0	0.0	No
		21	0.0	0.0037	0.0	0.0	0.0	0.0	0.0	No
		21	0.0	0.0033	0.0	0.0	0.0	0.0	0.0	No

^aGE, genome equivalents of C. burnetii determined by quantitative real-time PCR targeting IS1111.

^bp.i., postinfection.

^cND, not done.

^dNA, not applicable.