Alphapapillomavirus

Alphapapillomavirus is a genus of the Papillomaviridae family. Members of this genus are small, non-enveloped double-stranded DNA viruses that infect keratinocytes of stratified squamous epithelia, primarily at mucosal and anogenital sites in humans and other primates. The genus contains many human papillomavirus (HPV) types that cluster into multiple species; Alphapapillomaviruses are distinguished from other genera in part by their mucosal tropism and genome features.

Clinical relevance and disease associations vary by type. Many Alphapapillomavirus types are associated with disease in humans. High-risk mucosal types, notably HPV-16 and HPV-18 and related types, are strongly linked to cervical, anal, oropharyngeal, and other cancers. Low-risk mucosal types, such as those that cause genital warts and juvenile-onset respiratory papillomatosis, also belong to this genus. HPV infections are typically sexually transmitted; most infections are transient, with immunity developing over time.

Prevention and vaccination efforts target Alphapapillomavirus types. Prophylactic vaccines cover several Alphapapillomavirus types—for example, the nonavalent Gardasil 9 targets HPV-6, -11, -16, -18, -31, -33, -45, -52, and -58. Screening programs, including cytology and HPV DNA testing, reduce cervical cancer incidence by enabling earlier detection and management of precancerous lesions.