HPV genotyping was performed with the use of the HPV Linear Array (Roche Diagnostics), as described previously.26 (link),27 (link) HPV genotypes 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68 were considered the primary high-risk (carcinogenic) genotypes.28 (link),29 (link) (We included HPV genotype 66 [HPV-66] in our definition of carcinogenic HPV genotypes after its reclassification, in 2005.29 (link)) For the primary analyses of HPV prevalence, we excluded subjects who were HPV-negative and had no detectable beta-globin in the sample, since the presence of cellular material could not be demonstrated.
Active Treponema pallidum infection was determined by means of a positive rapid plasma re-agin test (Becton Dickinson) or a toluidine red unheated serum test (TRUST) (New Horizons Diagnostics) and was confirmed by a positive T. pallidum particle agglutination assay (Serodia TP-PA kit, Fujirebio).