Genital warts

Genital warts also called condyloma acuminata, anogenital warts or venereal warts, are a common sexually transmitted infection caused by human papillomavirus (HPV) that are passed on by vaginal and anal sex, sharing sex toys and, rarely, by oral sex. Human papillomavirus (HPV) is a small, non-enveloped, double-stranded DNA virus and there are more than 200 HPV types ¹. HPVs are called papillomaviruses because some HPV types cause papillomas (warts), which are non-cancerous tumors. Each HPV virus is given a number, which is called an HPV type. Figure 1 below shows the different groups of HPV types and the problems each group can cause. About 40 of those HPV types affect the genitals. HPV subtypes number 6 and 11 cause 90% of genital warts and are considered low risk because they very rarely will cause genital or anal cancer ², ³, ⁴, ⁵. On the other hand, HPV subtypes 16 and 18, for example, are considered high risk because, although they rarely cause genital warts, they can cause cancer, including cancers of the cervix (the base of the womb at the top of the vagina), vagina, vulva (the area around the outside of the vagina), penis, anus, and parts of the mouth and throat ⁶, ⁷. Approximately 65-70% of cervical cancers are caused by HPV types 16 or 18 ⁸. In addition, about 10% of HPV-related cancers are caused by HPV types 31, 33, 45, 52, and 58 ². In the United States, approximately 45,000 HPV-related cancers are diagnosed each year, with cancer of the cervix the most common among women and cancer of the throat (oropharynx) the most common in men ⁷.

The human papillomavirus (HPV) are spread through sexual contact with an infected partner. HPV is spread by skin-to-skin contact during sexual activity; there does not need to be vaginal or anal intercourse to spread the infection. Most people who become infected with HPV will not have symptoms and will clear the infection on their own. For people who do develop genital warts, there are many options for treatment, all of which are meant to remove the visible warts. There is no cure for genital warts.

In the United States three HPV vaccines are licensed: Ceravrix, a 2-valent vaccine (2vHPV) that targets HPV types 16 and 18; Gardasil, a 4-valent vaccine (4vHPV) that targets HPV types 6, 11, 16, and 18; and Gardasil 9, a 9-valent vaccine (9vHPV) that targets HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58. Types 16 and 18 account for 65-70% of all cervical cancers, whereas the five additional types targeted by the 9-valent vaccine account for 10% ². HPV types 6 and 11 cause >90% of genital warts. Only Gardasil 9 (9vHPV) vaccine is available in the United States ⁹.

• Gardasil, a 4-valent vaccine (4vHPV) that protects against the 4 strains of HPV (HPV types 6, 11, 16, and 18) that cause 70% of cervical cancers and 90% of genital warts. In the US, Gardasil is approved for girls/women and boys/men ages 9–26. In 2011, Health Canada approved the vaccine for women up to the age of 45.
• Gardasil 9, a 9-valent vaccine (9vHPV) that targets HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58, is highly effective in preventing urogenital cancers and anogenital warts.

Treatment for genital warts needs to be prescribed by a doctor. The type of treatment you’ll be offered depends on what the warts look like and where they are. Your doctor will discuss this with you.

Genital warts treatments include:

• Cream or liquid: you can usually apply this to the warts yourself a few times a week for several weeks, but in some cases you may need to go to a sexual health clinic where a doctor or nurse will apply it. These treatments can cause pain, irritation or a burning sensation.
• Surgery: a doctor or nurse may cut, burn or use a laser to remove the warts. This can cause pain, irritation or scarring.
• Freezing: a doctor or nurse freezes the warts. Sometimes the treatment is repeated several times. This can cause pain.

It may take weeks or months for treatment to work and the warts may come back. In some people, the treatment does not work.

There’s no cure for genital warts, but it’s possible for your body to fight the virus over time.

What is the human papillomavirus?

The human papillomavirus (HPV) is actually a group of double-stranded DNA viruses.

• There are at least 100 different types of HPV; at least 40 can infect the anogenital area. Many others cause warts on other areas of skin.
• At least 75% of sexually active adults have been infected with at least one type of anogenital HPV at some time in their life.
• HPV is incorporated into skin cells and stimulates them to proliferate, causing a visible wart.
• Visible anogenital warts are often easy to diagnose by their typical appearance. They are usually due to HPV types 6 and 11.
• Most do not develop visible warts. However, the infection may show up on a cervical smear. This is known as subclinical infection.
• Some strains of HPV cause anogenital cancer. These strains may not cause visible warts but they remain contagious.

Figure 1. HPV types

How is human papillomavirus transmitted?

Visible genital warts and subclinical human papillomavirus (HPV) infection nearly always arise from direct skin to skin contact.

• Sexual contact. This is the most common way amongst adults.
• Transmission is more likely from visible warts than from subclinical HPV infection.
• Oral sex. HPV appears to prefer the genital area to the mouth however.
• Vertical (mother to baby) transmission through the birth canal.
• Auto (self) inoculation from one site to another.
• Fomites (ie from objects like bath towels). It remains very controversial whether warts can spread this way.

Often, warts will appear three to six months after infection but they may appear months or even years later.

Genital warts causes

Anogenital warts are an infection caused by specific human papillomavirus (HPV) types, most commonly HPV types 6 and 11. Anogenital warts will usually appear three to six months after infection but they may appear months or even years later. Anogenital warts are usually a sexually transmitted infection (STI) due to friction-induced microabrasions during skin-to-skin contact ³. Transmission rates of HPV between sex partners are high, and transmission often occurs from persons with HPV who are asymptomatic or have subclinical infection ¹⁰, ¹¹. Consistent and correct use of condoms reduces the risk for genital HPV acquisition or transmission, and therefore reduces the risk for HPV-associated diseases ¹². Condom use, however, does not entirely prevent transmission of HPV, since exposure to HPV can occur in areas that are not fully covered or protected by a condom ⁶. Treatment of warts or cervical cellular abnormalities will reduce, but not eliminate, the risk of transmission. Transmission of HPV through nonsexual routes can occur, but is uncommon ¹³, ¹⁴. Mothers with low-risk genital HPV types can rarely transmit HPV to their newborn during delivery, but if transmission does occur, HPV has the potential to cause recurrent respiratory papillomatosis in children ¹⁵, ¹⁶.

Genital warts are almost always spread through sexual activity. Your warts don’t have to be visible for you to spread the infection to your sexual partner.

• Sexual contact. This is the most common way amongst adults. Transmission is more likely from visible warts than from subclinical or latent HPV infection.
• Oral sex. HPV appears to prefer the genital area to the mouth.
• Vertical (mother to baby) transmission through the birth canal.
• Auto (self) inoculation from one site to another.

As anogenital warts are usually sexually acquired, they are most commonly observed in young adults between the ages of 15 and 30 years. They are highly contagious. However, anogenital warts are rare in people who have been vaccinated against the benign HPV types in childhood before beginning sexual activity. Anogenital warts have been reported in a number of studies to be more common in males than females.

Patients who are immunocompromised due to drug-induced immunosuppression or HIV infection are at particular risk of acquiring HPV and developing anogenital warts.

Anogenital warts can also affect infants and young children. The virus may be acquired during birth or from the hands of carers.

Risk factors for getting genital warts

Most people who are sexually active get infected with genital HPV at some time. Factors that can increase your risk of becoming infected include:

• Having unprotected sex with multiple partners
• Having had another sexually transmitted infection
• Having sex with a partner whose sexual history you don’t know
• Becoming sexually active at a young age
• Having a compromised immune system, such as from HIV or drugs from an organ transplant

Genital warts prevention

Limiting your number of sexual partners and being vaccinated will help prevent you from getting genital warts. Using a condom every time you have sex is a good idea, but won’t necessarily protect you from genital warts.

HPV vaccination

The Centers for Disease Control and Prevention (CDC) recommends routine HPV vaccination for girls and boys ages 11 and 12, although it can be given as early as age 9. It’s ideal for girls and boys to receive the HPV vaccine before they have sexual contact ⁹.

Side effects from the HPV vaccines are usually mild and include soreness at the injection site, headaches, a low-grade fever or flu-like symptoms.

The CDC now recommends that all 11- and 12-year-olds receive two doses of HPV vaccine at least six months apart, instead of the previously recommended three-dose schedule. Younger adolescents ages 9 and 10 and teens ages 13 and 14 also are able to receive vaccination on the updated two-dose schedule. Research has shown that the two-dose schedule is effective for children under 15.

Teens and young adults who begin the vaccine series later, at ages 15 through 26, should continue to receive three doses of the vaccine.

The CDC now recommends catch-up HPV vaccinations for all people through age 26 who aren’t adequately vaccinated.

The U.S. Food and Drug Administration (FDA) recently approved the use of Gardasil 9 for males and females ages 9 to 45. If you’re ages 27 to 45, discuss with your doctor whether he or she recommends that you get the HPV vaccine.

In the United States three HPV vaccines are licensed: Ceravrix, a 2-valent vaccine (2vHPV) that targets HPV types 16 and 18; Gardasil, a 4-valent vaccine (4vHPV) that targets HPV types 6, 11, 16, and 18; and Gardasil 9, a 9-valent vaccine (9vHPV) that targets HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58. Types 16 and 18 account for 65-70% of all cervical cancers, whereas the five additional types targeted by the 9-valent vaccine account for 10% ². HPV types 6 and 11 cause >90% of genital warts. Since late 2016, only Gardasil 9 (9vHPV) vaccine is available in the United States ⁹.

• Gardasil, a 4-valent vaccine (4vHPV) that protects against the 4 strains of HPV (HPV types 6, 11, 16, and 18) that cause 70% of cervical cancers and 90% of genital warts. In the US, Gardasil is approved for girls/women and boys/men ages 9–26. In 2011, Health Canada approved the vaccine for women up to the age of 45.
• Gardasil 9, a 9-valent vaccine (9vHPV) that targets HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58, is highly effective in preventing urogenital cancers and anogenital warts.

HPV vaccine may be available at doctor offices, community health clinics, school-based health centers, and health departments.

Who should NOT get HPV vaccine?

Tell your doctor about any severe allergies. Some people should NOT get some HPV vaccines if:

• They have ever had a life-threatening allergic reaction to any ingredient of an HPV vaccine, or to a previous dose of HPV vaccine.
• They have an allergy to yeast (Gardasil and Gardasil 9).
• They are pregnant.

HPV vaccines are safe for children who are mildly ill, like those with a low-grade fever of less than 101 degrees, a cold, runny nose, or cough. People with a moderate or severe illness should wait until they are better.

Genital warts signs and symptoms

Genital warts affect the moist tissues of your genital area. Genital warts can look like small, flesh-colored bumps or have a cauliflower-like appearance with a folded irregular surface a few millimeters in diameter. In many cases, the warts are too small to be visible. Genital warts may join together to form plaques up to several centimeters across. A linear pattern may be seen if the HPV virus has been inoculated along a scratch or tear in the skin.

In women, genital warts can grow on the vulva, the walls of the vagina, the area between the external genitals and the anus, the anal canal, and the cervix. In men, they may occur on the tip or shaft of the penis, the scrotum, or the anus.

Genital warts can also develop in the mouth, throat, around the lips and conjunctiva of the eye of a person who has had oral sexual contact with an infected person.

The signs and symptoms of genital warts include:

• Small, flesh-colored, brown or pink swellings in your genital area
• A cauliflower-like shape caused by several warts close together
• Itching or discomfort in your genital area
• Bleeding with intercourse

Genital warts can be so small and flat as to be invisible. Rarely, however, genital warts can multiply into large clusters in someone with a suppressed immune system.

Genital warts complications

Anogenital warts are contagious and easily spread to your sexual partners. Anogenital warts can impact psychosexual functioning and quality of life.

HPV infection complications can include:

• Cancer. Cervical cancer has been closely linked with genital HPV infection. Certain types of HPV also are associated with cancers of the vulva, anus, penis, and mouth and throat. HPV infection doesn’t always lead to cancer, but it’s important for women to have regular Pap tests, particularly those who’ve been infected with higher risk types of HPV.
• Problems during pregnancy. Rarely during pregnancy, warts can enlarge and multiply, making it difficult to urinate. Warts on the vaginal wall can inhibit the stretching of vaginal tissues during childbirth. Large warts on the vulva or in the vagina can bleed when stretched during delivery. Extremely rarely, a baby born to a mother with genital warts develops warts in the throat. The baby might need surgery to keep the airway from being blocked. HPV can be transmitted to the baby resulting in recurrent respiratory papillomatosis in the infant.

Genital warts diagnosis

Anogenital warts are usually diagnosed clinically by their appearance.

Skin biopsy is sometimes necessary to confirm the diagnosis of viral wart, particularly if there is concern of anogenital cancer.

In some circumstances, researchers and clinicians may wish to confirm the presence or absence of HPV. One commercially available qualitative test for HPV is the COBAS 4800 Human Papillomavirus (HrHPV) Test, which evaluates 14 high-risk (HR oncogenic) HPV types.

Pap tests

For women, it’s important to have regular pelvic exams and Pap tests, which can help detect vaginal and cervical changes caused by genital warts or the early signs of cervical cancer.

During a Pap test, your doctor uses a device called a speculum to hold open your vagina and see the passage between your vagina and your uterus (cervix). He or she will then use a long-handled tool to collect a small sample of cells from the cervix. The cells are examined with a microscope for abnormalities.

HPV test

Only a few types of genital HPV have been linked to cervical cancer. A sample of cervical cells, taken during a Pap test, can be tested for these cancer-causing HPV strains.

This test is generally reserved for women age 30 and older. It isn’t as useful for younger women because for them, HPV usually goes away without treatment.

Genital warts treatment

There is no cure for genital warts. The goal of treatment is to remove visible warts and decrease the risk of spreading the virus ¹⁷. However, available therapies reduce but do not completely eliminate the risk of HPV transmission ¹⁸. In addition, there are no data that suggest treatment of genital warts impacts the subsequent risk of anogenital HPV-related cancer ¹⁸. Although appropriate treatment can induce wart-free periods, subsequent recurrences are common, with a 20 to 50% recurrence rate at 3 to 6 months post-treatment ¹⁹. Reappearance of genital warts within the first several months usually indicates recurrence rather than reinfection. If left untreated, visible genital warts persist with or without rapid increase in the number, but some regress spontaneously. Because spontaneous resolution of anogenital warts can occur, some individuals may choose to defer treatment and await possible spontaneous resolution ¹⁸. In addition, there are no data that suggest treatment of genital warts impacts the subsequent risk of anogenital HPV-related cancer ¹⁸.

If your warts aren’t causing discomfort, you might not need treatment. But if you have itching, burning and pain, or if you’re concerned about spreading the infection, your doctor can help you clear an outbreak with medications or surgery. However, warts often return after treatment. There is no treatment for the HPV virus itself.

Home remedies for genital warts

To be successful you must identify and reach the warts, and follow the application instructions carefully. Available treatments include:

• Podophyllotoxin 0.5% gel or solution (Condylox®). This should not be used during pregnancy.
• Imiquimod 3.75% cream (Zyclara). Imiquimod cream appears to boost your immune system’s ability to fight genital warts. Apply once daily for up to 8 weeks. Avoid sexual contact while the cream is on your skin. It might weaken condoms and diaphragms and irritate your partner’s skin. One possible side effect is skin redness. Other side effects might include blisters, body aches or pain, a cough, rashes, and fatigue.
• Imiquimod 5% cream (Aldara). Apply once daily (at bedtime) 3 times a week for up to 16 weeks.
• Sinecatechins (Veregen). Sinecatechins cream is used for treatment of external genital warts and warts in or around the anal canal. Sinecatechins 15% ointment should be administered 3 times/day using a finger to apply a 0.5 cm strand of ointment to each anogenital wart; the goal is to cover the wart entirely with a thin layer of the sinecatechins. The ointment should not be washed off after application. Genital, anal, and oral sexual contact should be avoided while sinecatechins ointment is present on the skin. This treatment can be administered for up to 16 weeks. Treatment with sinecatechins is not recommended for persons with genital herpes or for immunocompromised persons, including those with HIV. Side effects, such as reddening of the skin, itching or burning, and pain, are often mild.

Don’t try to treat genital warts with over-the-counter wart removers. These medications aren’t intended for use in the genital area.

Treatments provided at a medical clinic

Genital wart treatments that can be applied directly to your skin by a physician:

• Imiquimod (Aldara, Zyclara). This cream appears to boost your immune system’s ability to fight genital warts. Avoid sexual contact while the cream is on your skin. It might weaken condoms and diaphragms and irritate your partner’s skin. One possible side effect is skin redness. Other side effects might include blisters, body aches or pain, a cough, rashes, and fatigue.
• Podophyllin and podofilox (Condylox). Podophyllin is a plant-based resin that destroys genital wart tissue. Your doctor applies 15–25% solution. Podofilox contains the same active compound, but you can apply it at home. Never apply podofilox internally. Additionally, this medication isn’t recommended for use during pregnancy. Podophyllin resin has been associated with multiple reports of systemic toxicity when this agent was applied to large lesions or when left on for longer periods than recommended ²⁰. Side effects can include mild skin irritation, sores or pain.
• Trichloroacetic acid (TCA) or bichloroacetic acid (BCA) 80%–90% solution: The application of trichloroacetic acid or bichloroacetic acid 80-90% solution should only be performed by an individual with training in this application and for treatment of small lesions and can be used for internal warts. These acid agents destroy wart tissue by causing chemical coagulation of proteins. Only a small amount of the solution should be applied to the wart and the solution should dry before the patient moves. If too much is applied or the patient experiences pain, sodium bicarbonate (i.e. baking soda) can be applied to neutralize the acid; the sodium bicarbonate is typically applied as a liquid soap preparation or powdered with talc. Side effects can include mild skin irritation, sores or pain.
• Freezing with liquid nitrogen (cryotherapy). Liquid nitrogen is used to freeze the warts. Freezing works by causing a blister to form around your wart. As your skin heals, the lesions slough off, allowing new skin to appear. You might need to repeat the treatment. The main side effects include pain and swelling.
• Surgical removal. This may need to be performed by a specialist with local anesthesia; usually for large amounts of warts and you might have pain afterward. You might need surgery to remove larger warts, warts that don’t respond to medications or, if you’re pregnant, warts that your baby can be exposed to during delivery.
• Laser treatment. Carbon dioxide laser treatment is useful for a large amount of urethral or vaginal warts. Side effects can include scarring and pain.
• Electrocautery. This procedure uses an electrical current to burn off warts. You might have some pain and swelling after the procedure.

Most of these treatments require multiple applications. If there is no improvement after 3 treatment cycles or if the warts are not gone after 6 treatment cycles, your doctor will usually switch you to a different medication. Common side effects of all treatments include skin irritation and redness. Some people may also develop scars at the site of the warts.

Genital warts during pregnancy

Genital warts can proliferate rapidly and become more friable during pregnancy. Watchful waiting is acceptable with smaller lesions. During pregnancy, cryotherapy, trichloroacetic acid, bichloroacetic acid, and surgical removal may be safely used ¹⁷. Cytotoxic agents (podophyllin, podofilox, imiquimod) should not be used during pregnancy ¹⁷. Although pregnant women with genital warts have a risk of transmitting HPV to their child during a vaginal birth, Cesarean section delivery should not be performed solely to prevent transmission to the neonate, since it is unclear whether Cesarean delivery prevents respiratory papillomatosis among infants ¹⁷.

Genital warts in immunocompromised patients

The general approach to the treatment of genital warts in persons with HIV is the same as for those without HIV ¹⁷. Persons with HIV, particularly those individuals with advanced immunosuppression, often have larger or more numerous warts that do not respond as well to therapy, and recurrences occur more frequently after treatment. High-grade squamous intraepithelial lesions (HSIL) and invasive cancer arising within the region of a genital wart (or resembling genital warts) are more frequent in immunocompromised patients; therefore, hyperpigmented lesions and lesions that persist despite treatment (especially in the perianal area) should be promptly evaluated by biopsy. The role of genital warts (or irritated post-treatment sites) in HIV transmission has not been well characterized.

Genital warts prognosis

While genital warts can be challenging to treat with the lesions requiring multiple treatments or a combination of treatments over time. Surgical excision is the only treatment option with clearance rates near 100 percent, although genital warts can recur after all treatment types. In fact, recurrence of lesions after clearance is seen 20 to 30 percent of the time. The recurrence rates for genital warts treated with topical podophyllotoxin treatments have a clearance rate of 45 to 83 percent and a recurrence rate of 6 to 100 percent. Imiquimod treatments have a lower rate of recurrence at 6 to 26 percent and a clearance rate of 35 to 68 percent. Sinecatechins ointment clears 47 to 59 percent of condyloma acuminata, and only 7 to 11 percent of patients have a recurrence of lesions after clearance. Cryotherapy with liquid nitrogen clears 44 to 75 percent of genital warts with a 21 to 42 percent recurrence rate. Treatment with trichloroacetic acid solution clears 56 to 81 percent of lesions and 36 percent of lesions recur after clearance ²¹.

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