Viral

HPV

The most common STI of all, spread skin-to-skin, and largely preventable by vaccine.

What's at stake: Serious

Most infections clear on their own, but high-risk types cause cervical, anal and throat cancers. Vaccine-preventable.

Cause

Virus (HPV, 40+ genital types)

Asymptomatic

Most infections

Curable

Clears on its own; no antiviral cure

Vaccine

Yes, covers ~90% of HPV cancers

Overview

Human papillomavirus (HPV) is a family of more than 100 virus types, around 40 of which infect the genital area. It is so common that most sexually active people acquire it at some point. The great majority of infections clear on their own within 1 to 2 years, but persistent infection with high-risk types (notably 16 and 18) causes nearly all cervical cancer and many anal, penile, vulvar and throat cancers, while low-risk types (6 and 11) cause genital warts. Because HPV spreads through skin-to-skin genital contact rather than fluids, condoms reduce but do not eliminate transmission. Per-act figures in this tool are illustrative and carry wide uncertainty.

How it spreads

Skin-to-skin genital contact during vaginal, anal, or oral sex
Genital contact without penetration (the virus lives on skin condoms don't cover)
Oral sex, linked to a rising share of throat (oropharyngeal) cancers
Rarely, mother to baby during birth

Symptoms

Most infections cause no symptoms at all
Genital warts (low-risk types 6 and 11): small bumps on the genitals or anus
High-risk types cause no symptoms but can lead to pre-cancerous cell changes
Abnormal cervical screening (smear/Pap) results

Most HPV infections are completely silent and clear without treatment. There is no routine HPV test for men, and it is not part of a standard STI screen. Cervical screening detects the cell changes high-risk HPV can cause. This means a 'clear' STI panel does not rule HPV out.

Vaccine

The HPV vaccine (Gardasil 9) protects against the types that cause around 90% of HPV cancers and genital warts. It works best when given before any exposure (hence routine vaccination of adolescents), but is still recommended for many adults. It does not treat an existing infection or cover every type, so screening is still important. This calculator treats a vaccinated person as protected, a simplification, since protection is high but not absolute.

Treatment

There is no treatment for the virus itself; the immune system usually clears it. Treatment targets what HPV causes: genital warts can be removed (creams, freezing, minor procedures), and pre-cancerous cervical changes are treated to prevent cancer. This is why regular cervical screening matters.

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Educational purposes only. Consult a healthcare provider for personal medical advice.