Table 1.

Demographic and Clinical Characteristics of the Study Cohort

	Study group
Demographic characteristics	Febrile patients	Encephalitic patients	Blood donors	Total
No. participants	588	44	800	1432
No. males	182	27	658	867
No. females	406	17	142	565
Male:female ratio	1:2.2	1:0.6	1:0.2	1:0.7
Age range (years)	1–73	1–79	18–60	1–79
Mean age	28	33	32	31
State of residence:
(1) Nuevo Leon	588	43	767	1398
(2) Coahuila	0	0	8	8
(3) Tamaulipas	0	1	25	26