This study investigated the influence of the host's CCR5 genotype in human brucellosis. Genotype analysis for the CCR5delta32 mutation was performed in 185 brucellosis patients and 141 healthy volunteers, all recruited in northern Greece. In the brucellosis-infected patients the CCR5delta32 genotype distribution showed a significant deviation from the Hardy-Weinberg equilibrium (p = 0.030), owing to the presence of 2 individuals homozygous for delta32 among the 185 brucellosis patients compared with none of the 141 controls. Extended studies should be performed to confirm an association between CCR5 genotype and the risk of acquiring brucellosis.