CCL2 and infection: All four negative factors proved to be significant negative determinants/predictors for previous infection (P< 0.0001), however only MCP-1, factor D and PAI-1 yielded area under curve (AUC) values > 0.8 (MCP-1: 0.966 [95% CI 0.938-0.995]; factor D: 0.914 [95% CI 0.838-0.990]; PAI-1: 0.885 [95% CI 0.787-0.984], Table 2; Figure 8A).