Human papillomavirus (HPV) is transmitted by skin-to-skin contact with an infected person. Transmission usually occurs during vaginal, oral or anal sex. Transmission can occur even if the infected person is not experiencing warts or other symptoms.

Some research suggests that genital HPV can be transmitted through inanimate objects like towels or underwear, but more research must be conducted to fully understand these modes of transmission.

Risk factors for HPV include:

• Having multiple sex partners. Having sex with more than one person increases the risk of being infected with HPV.
  
  
• Having sex with a high-risk partner. Having sex with a person who has multiple sex partners or is known to be infected with HPV increases the risk of infection.
  
  
• Smoking cigarettes. If you have been exposed to HPV and smoke, the risk of developing symptoms increases. The risk of developing precancerous or cancerous conditions also increases.
  
  
• Having an impaired immune system. People with weakened immune systems, such as those with AIDS or certain other conditions, have an increased risk of acquiring HPV.