CD4 and infection: These factors included a Western European origin (odds ratio [OR], 1.35, P = 0.008), CD4 cell count (square root transformed) (OR: 0.82, P = 0.01), MSM (OR:1.80, P < 0.0001), subtype B (OR:2.06, P < 0.0001) and recent infection (OR:1.43, P = 0.001).