Human papillomavirus (pap-ah-LO-mah-VYE-rus) (HPV) is the most common sexually transmitted disease (STD) in the United States. HPV is a group of more than 150 related viruses of which more than 40 are sexually transmitted. The 40 HPV types that are sexually transmitted spread very easily through genital contact. HPV is passed on most often during vaginal, oral, and anal sex. A person can have HPV even if years have passed since they have had sexual contact with an infected person. It is also possible to get more than one type of HPV. Most people with HPV do not develop visible symptoms or severe health problems from it, and may pass it on to partners without ever realizing it. In 90% of cases, the body’s immune system clears HPV naturally within two or three years, but symptoms can persist for years. HPV is not the same as herpes. They are both viruses that can be passed on during sex, but they cause different symptoms and health problems.

High-risk types of HPV have been associated with cervical, vulvar, vaginal, penile, anal, and some head and neck cancers, with cervical cancer being the most common in women. At least 50% of sexually active people (mostly those who engage in high risk sexual behaviors with more than one partner) will have genital HPV at some time in their lives. Most people who become infected with HPV do not even know they have it and don’t know that they are passing it on to their partners. Latex condoms do not protect against HPV infection, which can occur in both male and female genital areas, whether covered or not by a latex condom. In some people, the high-risk HPV types can cause cell changes over time that can lead to cancer, especially if they are not treated. Although condoms do not prevent HPV infection, condom use may be associated with a lower rate of cervical cancer in those who choose to be sexually active and use them. Teens and young women in their first few years of sexual activity are more likely to become infected with an HPV. Cervical cancer occurs most often in women aged 30 years and older.

Sometimes, certain types of HPV can cause genital warts that are called papillomas, which are benign (noncancerous) tumors. The types of low-risk HPVs that cause warts to appear on or around the genitals or anus (condylomata acuminata) are HPV-6 and HPV-11. Genital warts appear as a small bump or group of bumps in the genital area. They can be practically any size or shape, and may be shaped somewhat like a cauliflower. These warts can appear within weeks or months, and sometimes even years after sexual contact with an infected partner, even if the partner had no visible signs of HPV. If left untreated, genital warts can increase in size or number, but they won’t turn into the cancer causing HPV, which is a different kind. Rarely, these types can also cause warts to grow in the throat—a condition called recurrent respiratory papillomatosis or RRP. It can sometimes block the airway, causing a hoarse voice or troubled breathing. Very rarely, a pregnant woman with genital HPV can pass HPV to her baby during delivery. In these cases, the child can develop RRP. Though RRP is rare, it is estimated that about 2,000 children get RRP every year in the U.S, when the mother transfers it to her newborn. Cesarean delivery is not recommended for women with genital warts to prevent it in their babies, because it is not clear whether cesarean delivery prevents RRP in infants and children.

These sexually transmitted HPVs cause only genital warts but others, called high-risk HPVs, can cause cancer. These high-risk kinds are called oncogenic, or carcinogenic HPVs. About 15 high-risk HPV types have been identified, including HPV types 16 and 18, which together cause most cervical cancers. Persistent or repeated infections with high-risk HPV types can cause cell abnormalities and if left untreated, areas of abnormal cells, called lesions, can develop into cancer. Persistent HPV infections are now recognized as the cause of almost all cervical cancers, which are almost completely preventable with education of safe sex practices (long term monogamous relationships). In spite of the preventability of the disease, cervical cancer is diagnosed in nearly half a million women each year worldwide, claiming a quarter of a million lives annually. Cervical cancer is preventable with safe sex practices, available screening tests, and a vaccine for those at risk. Cervical cancer is also treatable with long survival and good quality of life if found early enough. To prevent cervical cancer, it is important to practice safe sex habits, get vaccinated when necessary, and get screened regularly if there’s any possibility of risk, whether in yours or your spouse’s behavior.

There are two vaccines (Cervarix and Gardasil) for women and teens that are effective in preventing infection with the two HPV types that cause most cervical cancers. The best is the Gardasil vaccine, which also prevents the two types of infection that cause most genital warts. It should be noted that these vaccines do not protect against all kinds of cancers. Though both vaccines are recommended for 11 and 12 year-old girls, and for females 13 through 26, who did not get them when they were younger, these extreme measures are not usually necessary for young girls who are virgins (not sexually active.) While these vaccines can be given to at risk girls as young as 9 years of age, they are probably not necessary unless the child has been or may be sexually compromised in some way. It is recommended that females get all three doses for the best protection and the same vaccine brand for all three, if necessary. The vaccines are most effective when given before a person’s first sexual contact, or whenever she is at risk and could be exposed to HPV.

Whether an HPV-infected woman develops cervical cancer depends on a variety of factors acting together with infection by high-risk HPV types. Factors that tend to increase the risk of cervical cancer in women persistently infected with high-risk HPV types include having many sexual partners, having many children by multiple partners, smoking, and possibly heavy drinking and drug use, which often cause poor choices in sexual conduct. Those who are sexually active and participate in high risk behaviors are at risk for contracting sexually transmitted HPV infections, even if they’re an unwilling participant, such as being a rape victim or a victim of childhood sexual abuse. It is difficult, at best, to determine whether a partner or perpetrator of a crime, who has been sexually active in the past is infected with an STD, so a wise choice of a partner and avoidance of dangerous situations should be priority for teens and women to be safe. Being in a long-term, mutually monogamous relationship with an uninfected partner is the best protection against the risk of sexually transmitted diseases.

There are four major steps in cervical cancer development, which are infection of the cervix, viral persistence, progression of persistent infection to cervical precancer, and cancer invasion. Persistent infections and precancer are usually established within 5-10 years of new infections. Invasive cancer happens over many years, even decades, in women with precancer, usually in those between 35-55 years of age. Each type of HPV acts as an independent infection, with differing carcinogenic risks linked to each. Cervical cancer usually does not have symptoms until it is quite advanced and usually too late to do anything about it. HPV-related cancers are virtually undetectable without a Pap test (a screening test to detect cervical cell changes) until they are far advanced and very hard to treat. For this reason, it is important for women to get regular Pap 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 (see www.cancer.gov). Cervical cancer can be prevented with routine cervical cancer screening and follow-up of abnormal Pap test results. The Pap test can find abnormal cells on the cervix so that they can be removed. An HPV DNA test, which can find HPV on a woman’s cervix, may also be used with a Pap test in some cases. HPV DNA tests can detect the presence of a viral infection before any cell abnormalities become visible. HPV DNA tests are available for follow-up testing of women with cell abnormalities on a Pap test. Even women who have had the vaccine need regular cervical cancer screening because it does not protect against all cervical cancers.

The HPV tests on the market are only used to help screen for cervical cancer. There is no basic test for women to check whether or not they have an HPV. Although there is no medical treatment for HPV infections, there are treatments for the problems that HPV causes. The cervical lesions and warts that result from such infections can be treated with cryosurgery (freezing), LEEP (loop electrosurgical excision procedure, or removal of tissue using a heated wire loop), and conization (removal of a cone-shaped piece of tissue from the cervix and cervical canal). Visible genital warts can also be removed by the patient with medications. Some people choose not to treat them, but wait to see if they go away on their own. Cervical cancer is most treatable when it is diagnosed and treated early, but most women who get routine Pap tests and follow ups as needed can identify problems before cancer develops. Prevention measures, such as safe sex in a mutually monogamous relationship, regular Pap tests, and getting the vaccine if there’s any question of infidelity, are always better than any treatment after getting the disease. [see www.cancer.org.] People can lower their risk of getting HPV by choosing a partner who has had no prior sex partners and by staying in a faithful relationship with one partner who is also faithful. But even people with only one lifetime sex partner can get HPV if their partner has had prior sexual relationships or is unfaithful. And it may not be known if a partner who has been sexually active in the past is currently infected. That’s why the only sure way to prevent HPV is for both partners to remain abstinent until marriage and stay faithful once married.

The following Federal Government agencies can provide more information about HPV infection:

The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, supports research on HPV infection and offers printed materials. NIAID can be contacted at http://www.niaid.nih.gov/Pages/default.aspx. The CDC (Center for Disease Control), also offers support and information about HPV. Free educational literature about sexually transmitted infections and prevention methods is available from the CDC at http://www.cdc.gov/std. The CDC also makes information about HPV, including treatment guidelines available at http://www.cdc.gov/hpv/

References:

http://www.cdc.gov/hpv/

http://www.cdc.gov/cancer/hpv/

http://www.cdc.gov/std/hpv/stdfact-hpv.htm

http://www.cdc.gov/hpv/oldfiles/HPV-Cancer.html

http://www.cancer.gov/cancertopics/factsheet/Risk/HPV

http://www.cancer.gov/cancertopics/factsheet/Risk/HPV#r5