Table 2.

Spatio-temporal irregular clusters of annual measles incidence during 2004–2014

Type of cluster	Cluster period	Cluster center	No. of counties	LLR	RR	P-value*
Most likely cluster	2014	108.08 E, 22.92 N	5	1042.05	6.22	0.001
Secondary cluster 1	2013–2014	106.51 E, 24.83 N	10	764.37	4.24	0.001
Secondary cluster 2	2004–2005	109.76 E, 24.02 N	23	637.35	4.26	0.001
Secondary cluster 3	2007	108.11 E, 24.17 N	1	552.47	9.86	0.001

^*Kulldorff’s space-time scan statistics based on Poisson model and elliptical-cylinder scanning window