Table 3.

Distribution of isolates by category of epidemiological variables for all isolates, those from cluster 6 and cluster 8.

Variable	Category	Number and percentage of isolates (n = 53)	Number cluster 6 (n = 27)	Number cluster 8 (n = 7)
State	Queensland	36 (67.9%)	24 (88.9%)	6 (85.7%)
	New South Wales	17 (32.1%)	3 (11.1%)	1 (14.3%)
Production	Meat/Feedlot	41 (77.4%)	23 (85.2%)	6 (85.7%)
	Dairy	5 (9.4%)	1 (3.7%)	1 (14.3%)
	Unknown	7 (13.2%)	3 (11.1%)	0 (0%)
Sample site	Lung	38 (71.7%)	19 (70.4%)	6 (85.7%)
	Brain	3 (5.7%)	2 (7.4%)	1 (14.3%)
	Nasal	5 (9.4%)	1 (3.7%)	0 (0%)
	Other	3 (5.7%)	3 (11.1%)	0 (0%)
	Unknown	4 (7.5%)	2 (7.4%)	0 (0%)
Year of isolation	1989–1994	4 (7.5%)	4 (14.8%)	0 (0%)
	1995–2000	9 (17%)	6 (22.2%)	2 (28.6%)
	2001–2005	9 (17%)	7 (25.9%)	2 (28.6%)
	2006–2010	25 (47.2%)	6 (22.2%)	2 (28.6%)
	2011–2012	2 (3.8%)	1 (3.7%)	1 (14.3%)
	Unknown	4 (7.5%)	3 (11.1%)	0 (0%)
Sex	Male	13 (24.5%)	8 (29.6%)	1 (14.3%)
	Female	11 (20.8%)	4 (14.8%)	2 (28.6%)
	Unknown	29 (54.7%)	15 (55.6%)	4 (42.9%)
Origin	Introduced	23 (43.4%)	13 (48.2%)	4 (57.1%)
	Homebred	7 (13.2%)	5 (18.5%)	0 (0%)
	Unknown	23 (43.4%)	9 (33.3%)	3 (42.9%)
Age (months)	0–6	12 (22.6%)	6 (22.2%)	3 (42.8%)
	7–12	10 (18.9%)	5 (18.5%)	1 (14.3%)
	13–18	15 (28.3%)	7 (26%)	2 (28.6%)
	19–24	5 (9.4%)	3 (11.1%)	1 (14.3%)
	Unknown	11 (20.8%)	6 (22.2%)	0 (0%)
Other infections	IBRVa	1 (1.8%)	1 (3.7%)	0 (0%)
	Coronavirus	2 (3.7%)	1 (3.7%)	0 (0%)
	Pestivirus	1 (1.8%)	0 (0%)	1 (14.3%)
	Negativeb	13 (24.5%)	9 (33.3%)	1 (14.3%)
	Not tested	36 (67.9%)	16 (59.3%)	5 (71.4%)

^aInfectious bovine rhinotracheitis virus.

^bTested for at least one virus but all results were negative.