Oral and cervical human papillomavirus infection among female sex workers in Japan.

It has been reported recently that oral human papillomavirus (HPV) infection is associated with oropharyngeal squamous cell carcinomas. The aim of this study was to determine the prevalence of HPV infection and HPV types in the oral cavity and cervix of female sex workers in Japan. Oral and cervical swabs were taken from 196 female sex workers who visited a clinic for regular medical checkups in 2007, and genomic DNA was extracted from those specimens. The HPV L1 gene was amplified by polymerase chain reaction (PCR) using original and modified GP5(+)/6(+) primers, and genotyping was performed using the Kurabo GeneSquare Microarray or by sequencing cloned PCR products. HPV DNA was detected in the oral cavity of 12 (6.1%) women, with HPV-56 being the most common type (7/12). Likewise, HPV DNA was detected in the cervix of 103 (52.6%) women, with HPV-52 (30/103, 29.1%), followed by HPV-16 (24.3%) and HPV-56 (18.4%), being the most common. Of the 12 women with oral HPV infection, only two were infected with the concordant HPV genotype in the cervix. These findings suggest that oral HPV infection occurs independently of cervical HPV infection in this population, and that oral HPV infection may play a role in HPV transmission in Japan.