It is unclear how many HPV-infected women who become HPV DNA negative actually have complete viral clearance and how many continue to harbor the viral genome in the basal cells of the squamous epithelium, but at such a low copy number that they cannot be detected using standard molecular tests. Such undetectable, low-level infections are usually referred to as “latent infections”.....
Reactivation of a latent infection secondary to senescence of HPV-directed cellular immunity could easily explain many of the HPV infections that are detected in older women with a previously normal screening history and no new sexual partners.
8 Currently, it is impossible to distinguish between reactivation of a latent HPV infection and a newly acquired infection