An overview of human papillomaviruses and current vaccine strategies

Cervical cancer is one of the most common cancers in women worldwide, particularly in developing countries. The viral origin of cervical cancer has been proven beyond any reasonable doubt. Persistent infection with certain subsets of human papillomaviruses is recognized as a necessary cause for the development of cervical cancer. Persistence of oncogenic HPVs, immunodeficiency, high HPV viral load and cofactors like smoking, multiple sex partners and poor nutrition predispose to cervical cancer. Prophylactic vaccines using HPV virus-like particles containing capsid protein L1 have shown protection against disease in animals and are currently undergoing clinical trials. Therapeutic vaccines using HPV E6 and E7 proteins are also being investigated for their ability to remove residual infection.