Table 1. Demographic characteristics of the panel of studied sera.

	Nb of sera	Sex ratio (M/F)	Median age	Nb of sera in age groups
				0–20	21–40	41–60	>60	Unknown
Joumine	86	0,15	38	4	40	16	22	4
Mateur	484	0,37	57	30	100	154	194	6
Ras Jabel	244	0,31	50	16	66	102	60	0
Sejenane	240	0,61	53	17	65	68	88	2
Utique	219	0,33	52	2	74	75	68	0
Total	1273	0,37	53	69	345	415	432	12