Factors significantly associated with MRSA colonization included a history of hospitalization (RR = 2.2, P < 0.001), prior antibiotic use (RR = 1.4, P = 0.001), diabetes mellitus (RR = 4.4, P = 0.015), and HIV-positive status with a CD4 count below 200 cells/μL (RR = 2.8, P = 0.002). This evidence concerns the gene CD4 and diabetes mellitus.