Table 1.

Sociodemographic characteristics of blood donors and prevalence of T. gondii infection.

Characteristic	Number	Prevalence of T. gondii infection		P value
		Number	%
Age groups (years)
30 or less	206	15	7.3	0.001
31–50	186	38	20.4
>50	16	2	12.5
Gender
Male	334	47	14.1	0.45
Female	74	8	10.8
Birth place
Sonora state	366	49	13.4	0.59
Other Mexican states	39	5	12.8
Abroad	3	1	33.3
Residence area
Urban	373	45	12.1	0.008
Suburban	27	9	33.3
Rural	8	1	12.5
Educational level
No education	10	4	40.0	0.004
1 to 6 years	48	6	12.5
7–12 years	216	36	16.7
>12 years	134	9	6.7
Occupation
Laborera	328	51	15.5	0.01
Nonlaborerb	80	4	5.0
Socioeconomic level
Low	195	32	16.4	0.24
Medium	212	23	10.8
High	1	0	0.0

^aLaborer: construction, professional, business, agriculture, factory worker, and others.

^bNonlaborer: housewife, student, or no occupation.