HPV (human papillomavirus) is the most common sexually transmitted infection (STI) and there are more than 40 types of HPV that can infect the genital areas of males and females. These HPV types can also infect the mouth and throat.
HPV can cause serious health problems, including genital warts and certain cancers and there is way to know who will develop health problems from HPV and who will not. In most cases, people who become infected do not even know they have the virus and often, the virus will go away by itself before it causes any health problems. HPV is not the same as herpes or HIV (the virus that causes AIDS).
HPV is passed on through genital contact, most often during vaginal and anal sex so anyone who is having sex (or has ever had sex) can become infected with HPV. This virus may also be passed on during oral sex. HPV can be passed on between straight and same-sex partners—even when the infected person has no signs or symptoms.
Since most people do not know they are infected, they will pass the HPV on to a sex partner. That means that straight and same-sex partners can become infected. Because there are so many types of HPV, a person can get more than one type of the virus.
Health problems that can be caused by HPV include:
- Genital warts (warts on the genital areas); this type of HPV does not cause cancer;
- Recurrent respiratory papillomatosis (RRP), a rare condition in which warts grow in the throat;
- Cervical cancer, cancer on a woman’s cervix; and
- Other, less common, but serious cancers, including genital cancers (cancer of the vulva, vagina, penis, or anus), and a type of head and neck cancer called oropharyngeal cancer (cancer in the back of throat, including the base of the tongue and tonsils).
Signs and symptoms of health problems caused by HPV:
Genital warts usually appear as a small bump or group of bumps in the genital area. They can be small or large, raised or flat, or shaped like a cauliflower. Warts can appear within weeks or months after sexual contact with an infected partner—even if the infected partner has no signs of genital warts. If left untreated, genital warts might go away, remain unchanged, or increase in size or number. The types of HPV that can cause genital warts are not the same as the types of HPV that can cause cancers.
Cervical cancer usually does not cause symptoms until it is quite advanced. For this reason, it is important for women to get regular screening for cervical cancer. Screening tests can find early signs of disease so that problems can be treated early, before they ever turn into cancer.
RRP (Recurrent Respiratory Papillomatosis) is a condition in which warts grow in the throat. These growths can sometimes block the airway, causing a hoarse voice or trouble breathing.
There is no certain way to know which people infected with HPV will go on to develop cancer or other health problems. However, persons with weak immune systems (including persons with HIV) may be less able to fight off HPV and more likely to develop health problems from it.
For this reason, condoms should be used when having vaginal or anal sex. It is recommended that a condom or a dental dam be used when having oral sex.
HPV vaccines are safe and effective, and can protect males and females against some of the most common types of HPV. The HPV vaccines are given in three shots over six months; it is important to get all three doses. Boys and girls at ages 11 or 12 are most likely to have the best protection provided by HPV vaccines, and their immune response to vaccine is better than older women and men.
Girls and women: Two vaccines (Cervarix and Gardasil) are available to protect females against the types of HPV that cause most cervical cancers. One of these vaccines (Gardasil) also protects against most genital warts, and has been shown to protect against anal, vaginal, and vulvar cancers. Either vaccine is recommended for 11- and 12-year-old girls, and for females 13 through 26 years of age who did not get any or all of the shots when they were younger. These vaccines can also be given to girls beginning at 9 years of age.
Boys and men: One vaccine (Gardasil) is available to protect males against most genital warts and anal cancers. Gardasil is recommended for 11- and 12-year-old boys, and for males 13 through 21 years of age who did not get any or all of the shots when they were younger. Gay, bisexual, and other men who have sex with men should receive the vaccine through age 26 years. Males 22–26 years of age may also get the vaccine.