Table 2. Significant clusters identified by national cluster detection.

Maximum size of temporal window = 1 month
Cluster ID	Locations	Time period	Observedcases	Expectedcases	Relativerisk	p-value	Log-likelihoodratio	Nested withinCluster
1A	SA	3/2004	3	0.00089	3370.06	0.002	21.36	Nil
1B	NT, QLD	11/2004	36	12.60	2.86	0.036	14.77	2E, 2F, 2G, 3B
Maximum size of temporal window = 2 months
Cluster ID	Locations	Time period	Observed cases	Expected cases	Relative risk	p-value	Log-likelihood ratio	Nested within Cluster
2A	NT, QLD	1–2/2004	14	1.93	7.25	0.025	15.66	Nil
2B	SA	3/2004	3	0.00089	3370.06	0.002	21.37	Nil
2C	NT, QLD, WA	10–11/2004	71	28.06	2.54	0.001	23.06	Nil
2D	NT, QLD, WA	10–11/2004	67	26.16	2.57	0.001	22.25	Nil
2E	NT, QLD	10–11/2004	45	16.17	2.79	0.005	17.26	2C, 2D
2F	NT, QLD	10–11/2004	51	19.12	2.68	0.002	18.21	2C, 2D
2G	NT, QLD	10–11/2004	60	23.35	2.58	0.002	20.04	2C, 2D
2H	WA	12/2005–1/2006	14	1.28	10.96	0.002	20.78	Nil
Maximum size of temporal window = 3 months
Cluster ID	Locations	Time period	Observed cases	Expected cases	Relative risk	p-value	Log-likelihood ratio	Nested within Cluster
3A	SA	3/2004	3	0.00089	3370.06	0.002	21.37	Nil
3B	QLD	11/2004–1/2005	73	35.37	2.07	0.042	15.34	Nil
3C	QLD	11/2004–1/2005	76	36.22	2.11	0.021	16.62	Nil
3D	SA	3–5/2005	24	5.72	4.20	0.013	16.15	Nil
3E	WA	12/2005–1/2006	14	1.28	10.96	0.002	20.78	Nil
3F	NT, QLD	9–11/2007	26	4.60	5.66	0.001	23.66	3F
3G	NT, QLD, SA, WA	9–11/2007	36	8.20	4.40	0.001	25.49	Nil

SA – South Australia; NT- Northern Territory; QLD – Queensland; WA – Western Australia.