Type-Specific Incidence and Persistence of HPV Infection among Young Women in North India

Human papillomavirus (HPV) is one of the most common sexually transmitted viruses (Walboomers et al., 1999; Bosch et al., 2002; Zur Hausen 2002). Although there is conclusive evidence that HPV infection is a necessary cause of cervical cancer, the discrepancy between the high frequency of HPV infections in young sexually active women and the relatively low occurrence of cervical lesions in the same population suggests that HPV is not a sufficient cause for cervical neoplasia (Moscicki et al., 2001). Most of these HPV infections are found to be transient and only women who harbor persistent high risk HPV infection are at risk of developing cervical lesions. High risk HPV infections (hrHPV) seem to persist longer than infections with low risk HPVs (Franco et al., 1999; Woodman et al., 2001; Guiliano et al., 2002; Richardson et al., 2003; Munoz et al., 2004; Brown et al., 2005). To effectively design cervical cancer prevention strategies, information regarding the incidence, prevalence and clearance of HPV infections in a variety of populations is needed. However, little is known about the type-specific