Concordance of specific human papillomavirus types in sex partners is more prevalent than would be expected by chance and is associated with increased viral loads

Background. Genital human papillomavirus (HPV) infections are generally accepted to be sexually transmitted, but studies of HPV infections in sex partners are limited. We investigated HPV type-specific concordance and viral load in 238 heterosexual couples. Women with cervical intraepithelial neoplasia were the index patients in these couples. Methods. GP5+/6+ polymerase chain reaction (PCR), followed by reverse-line blot analysis, was used for the detection of 45 HPV types in cervical and penile scrape samples. Viral loads were subsequently determined in scrape samples positive for HPV types 16, 18, 31, and 33 by LightCycler-based real-time PCR assays. Results. A total of 89.9% of the women and 72.9% of their male partners were HPV positive. Predominantly high-risk HPV types were found in persons of both sexes, but infections with multiple and non-high-risk HPV types were more common in men. Of the HPV-positive couples, 57.8% of the men had the same HPV type as their partners; this rate was significantly higher than that expected by chance (P < .001). Moreover, these HPV-concordant men had higher penile scrape viral loads than did the non-HPV-concordant men. For HPV type 16 positive women, higher cervical viral loads were predictive of presence of HPV type 16 in their sex partners. Conclusions. In sexually active couples, HPV type concordance was more prevalent than expected by chance and was associated with increased viral loads. These data provide biological support for HPV transmission between sex partners.