Project 459558

Human papillomavirus (HPV) is the most common sexually transmitted infection. Most HPV infections are asymptomatic and clear spontaneously, while some persist and may result in anogenital and oropharyngeal cancers. Despite screening and HPV vaccination programs, high-risk HPV types account for over 5% of the worldwide cancer burden, highlighting the need for improvements in HPV prevention. Since most HPV infections clear on their own, the immune system likely plays an important role in preventing/clearing infections. The immune system produces HPV antibodies after natural infection or vaccination. Many questions remain however unanswered: 1) what triggers the immune system against specific HPV types, 2) how the immune system can prevent/clear infections, and 3) how an immune response affects HPV transmission between sexual partners. Whether HPV antibodies predict persistent infections and/or future cancer risk in an individual or are merely a result of past infections is also disputed. Understanding these issues may aid in developing new prevention strategies against HPV-related cancers. Moreover, as individuals become increasingly aware of their HPV status through HPV-DNA testing, they may want to know about the consequences of being infected by a virus that can cause cancer. Hence, this project will analyze data from a cohort study (2005-2014) of over 500 young, newly formed heterosexual couples. Longitudinal data on demographic characteristics, sexual behaviour, and medical history including HPV vaccination were obtained. Biological specimens (genital, blood, oral and hand) were collected and tested for HPV infections. Using these data, this project will describe patterns of HPV seropositivity (i.e., circulating HPV antibodies in blood serum) overtime, and identify factors associated with HPV prevalence, persistence and viral load at various anatomical sites. Therefore, this study will enable an in-depth investigation into the immune response to HPV infection.