Analysis by MIRU-VNTR of the cross-contamination alerts that could not be solved by RFLP. The numbers for each alert were assigned chronologically. For each alert the potential source/s (PS) and the cross-contamination alerts (CCA) are indicated. The MIRUtypes and the results (TP:True positivity, FP: False positivity) after analyzing the MIRU-VNTR fingerprints are shown. The MIRU-VNTR alleles which are different for the isolates from an alert are highlighted in bold. The loci which appear underscored mean that no amplification product was obtained. The loci with two values indicate that two alleles were simultaneously detected for that locus.