Association of ABO Blood Group Phenotype and Allele Frequency with Chikungunya Fever

Table 1

Univariate analysis for CHIK seropositivity.

Variables	Anti-CHIK IgG		P value	OR (95% CI)
	Positive (%); N = 314	Negative (%); N = 192
Age (years)			0.13
<40	97 (30.9)	76 (39.6)		Reference
40–60	148 (47.1)	80 (41.7)		1.45 (0.97, 2.17)
>60	69 (22)	36 (18.8)		1.5 (0.91, 2.48)
Gender			0.03
Male	110 (35)	49 (25.5)		Reference
Female	204 (65)	143 (74.5)		0.64 (0.43, 0.95)
ABO blood group			0.76
O	130 (41.4)	78 (40.6)	<0.001	Reference
A	80 (25.5)	46 (24)	0.003	1.04 (0.66, 1.65)
B	80 (25.5)	48 (25)	0.005	1 (0.63, 1.58)
AB	24 (7.6)	20 (10.4)	0.55	0.72 (0.37, 1.39)