Table 3. Comparative age distributions of the most common MLST clonal complexes by study area (first year of the study)*.

Clonal complex	Age group	Isolates		Incidence/100,000		Incidence ratio	95% confidence intervals	p value
		Rural	Suburban	Rural	Suburban
ST–21	0–14	2	14	6.65	17.68	0.38	0.04–1.64	–
	15–34	9	24	24.27	21.02	1.15	0.47–2.57	–
	35–54	12	18	24.38	15.14	1.61	0.71–3.53	–
	>55	13	13	20.17	11.43	1.76	0.75–4.13	–
ST–45	0–14	3	1	9.97	1.26	7.89	0.63–414.40	–
	15–34	1	4	2.70	3.50	0.77	0.02–7.78	–
	35–54	7	6	14.22	5.05	2.82	0.81–10.15	–
	> 55	10	3	15.51	2.64	5.88	1.51–33.24	<0.01
ST–257	0–14	2	1	6.65	1.26	5.26	0.27–310.48	–
	15–34	1	8	2.70	7.01	0.38	0.01–2.87	–
	35–54	3	8	6.09	6.73	0.91	0.15–3.77	–
	> 55	4	4	6.21	3.52	1.76	0.33–9.47	–
ST–443	0–14	1	0	3.32	0.00	–	–	–
	15–34	3	5	8.09	4.38	1.85	0.29–9.50	–
	35–54	0	6	0.00	5.05	–	–	–
	> 55	1	6	1.55	5.28	0.29	0.01–2.42	–
ST–48	0–14	1	2	3.32	2.53	1.32	0.02–25.27	–
	15–34	5	7	13.48	6.13	2.20	0.55–8.05	–
	35–54	0	4	0.00	3.36	–	–	–
	> 55	1	2	1.55	1.76	0.88	0.01–16.94	–
ST–206	0–14	0	0	0.00	0.00	–	–	–
	15–34	1	6	2.70	5.26	0.51	0.01–4.23	–
	35–54	5	5	10.16	4.21	2.42	0.56–10.49	–
	> 55	2	1	3.10	0.88	3.53	0.18–208.11	–
All cases	0–14	19	29	63.13	36.62	1.72	0.91–3.18	–
	15–34	48	87	129.45	76.20	1.70	1.17–2.44	<0.01
	35–54	54	87	109.71	73.18	1.50	1.05–2.13	0.02
	> 55	57	66	88.43	58.05	1.52	1.05–2.20	0.02

*Including all cases of campylobacteriosis reported for which age was available. Annual estimated incidences in 4 age groups were calculated for each clonal complex using estimates of the age-specific annual population for each local authority. Incidence ratios were calculated for rural incidence/suburban incidence and 95% confidence intervals calculated. Those data with a statistically significant difference between the study areas are shown in boldface type (level of significance p<0.05). MLST, multilocus sequence typing.