Warts are small, rough growths on the skin caused by infection with human papillomavirus (HPV). There are over 100 types of HPV that can cause warts on different parts of the body. Some types of HPV are spread through sexual contact and can cause genital warts. So are warts an STD (sexually transmitted disease)? The short answer is sometimes. Some types of warts are caused by HPV strains that are sexually transmitted, while other types have nothing to do with sexual contact.
What are Warts?
Warts are benign (non-cancerous) skin growths caused by infection with the human papillomavirus (HPV). HPV causes an excess production of keratin, a tough protective protein, resulting in rough, thickened skin. There are over 100 identified strains or types of HPV, many of which tend to infect specific areas of the body. The most common types of warts include:
- Common warts – Rough, rounded bumps that develop on hands and fingers
- Plantar warts – Hard, grainy growths that develop on the soles of the feet
- Flat warts – Smooth, flat-topped lesions that develop on the face, legs, or arms
- Genital warts – Soft, flesh-colored bumps in the genital area caused by sexually transmitted HPV
Warts are generally harmless, but can be bothersome or embarrassing depending on their location. They may spread to surrounding skin if picked or scratched. Most warts resolve without treatment after a period of months to years.
Are All Warts Caused by HPV?
The simple answer is yes – all warts are caused by infection with human papillomavirus. However, there are over 100 identified types of HPV and each strain tends to infect and cause warts on specific areas of the body. Only some HPV types are considered sexually transmitted infections that cause lesions in the genital area.
Sexually Transmitted HPV Types
There are approximately 40 HPV types that can be transmitted through sexual contact and lead to infections in the anogenital region. These include:
- HPV 6 and 11 – Cause about 90% of genital warts cases.
- HPV 16 and 18 – Known as “high risk” strains because they can lead to cellular changes that cause genital cancers.
Genital warts are soft, fleshy bumps that appear on the sex organs and anal area in both males and females. They are spread through vaginal, oral, and anal sexual activity with an infected partner. Using condoms reduces, but does not completely prevent, HPV transmission.
Non-Sexually Transmitted HPV
The majority of HPV strains are harmless and not spread by sexual contact. These types tend to infect and cause warts on specific areas of the body, such as:
- HPV 1, 2, 4 – Cause common warts of the hands and fingers.
- HPV 3, 10 – Cause flat warts on the face, arms, knees.
- HPV 27, 57 – Cause plantar warts on the soles of the feet.
These HPV types are transmittable by skin-to-skin contact, contact with contaminated objects or surfaces, or autoinoculation (spreading warts to other body parts). They do not require sexual activity for transmission.
Are Genital Warts an STD?
Yes, genital warts are sexually transmitted. They are caused by HPV types 6 and 11 in over 90% of cases. These strains of HPV only infect and cause warts in the moist membranes of the genital area, anus, mouth, and throat. They are spread primarily by genital-to-genital contact during vaginal and anal sex. Oral sex can transmit genital HPV to the mouth and throat.
Using condoms reduces, but does not eliminate, the risk of catching genital warts. Even with condoms, HPV can be spread by skin-to-skin contact with infected areas not covered by the condom. The virus can also live on sex toys and be transmitted that way.
Signs of Genital Warts
Genital warts may appear within weeks or months after contact with HPV 6 or 11. Signs include:
- Small, fleshy, pink or red bumps around the genital or anal areas
- Lesions may be solitary or clustered in a cauliflower-like shape
- Warts may be itchy, but are usually painless
- In women, warts may develop inside the vagina or on the cervix
- In men, lesions can form on the penis, scrotum, thighs, anus
Genital warts should always be checked by a doctor, who can confirm the diagnosis and provide treatment options.
Are Common Warts an STD?
No, the types of HPV that cause common warts are not sexually transmitted. Strains like HPV types 1, 2, 4 infect the outer layers of skin on hands and fingers. They produce rough, rounded bumps that may have a cauliflower-like surface.
Common warts are often acquired in childhood by touching contaminated surfaces. Sharing objects like towels, razors, and gym equipment can spread HPV. Autoinoculation can occur by picking or scratching warts and spreading virus to other areas.
Common warts are not spread by sexual contact and not considered an STD. However, warts that occur on the genitals, anus, groin or thigh may be mistaken for genital warts. Checking with a doctor can determine if genital-type HPV is present.
Are Plantar Warts an STD?
No, plantar warts are not sexually transmitted. They are caused by HPV types 1, 2, 4, 27, and 57. These strains infect the thick skin on the soles of the feet, toes, and heels. Plantar warts produce grainy bumps with tiny black dots that can be painful with walking and standing.
Plantar warts are often acquired by walking barefoot in public places like swimming pools, locker rooms, and showers. The virus shed from existing warts can enter the skin through tiny cuts and abrasions. Sharing footwear with an infected person can also spread plantar warts.
Therefore, plantar warts are not considered a sexually transmitted disease. However, plantar warts can occasionally occur on the genitals if the strain of HPV infects that skin. Checking with a doctor can determine the type of HPV causing unusual growths.
Are Facial/Flat Warts an STD?
Flat warts that develop on the face, hands, arms, and legs are not sexually transmitted. They are caused by “cutaneous” HPV strains like types 3, 10, and 28 that infect the outer skin layers.
Facial warts are often spread by skin-to-skin contact between children and family members. Shaving and minor skin abrasions make infection more likely in teens and adults. Shared items like towels, razors, and sports equipment can transmit flat wart virus as well.
Flat warts are not spread through sexual contact and are not considered an STD. However, HPV strains that cause flat warts can sometimes infect genital skin. Unusual flat lesions in the genital region should be evaluated by a doctor.
Can Warts Lead to Cancer?
Most types of warts will not lead to cancer, as they are caused by “low risk” strains of HPV. However, genital warts may signal infection with cancer-associated strains like HPV 16 and 18. Although strains 6 and 11 cause most genital warts, co-infection with high risk HPV occurs in 30-70% cases.
High risk HPV 16 and 18 cause cellular changes that can progress to genital or oral cancers if left untreated for years. Cancers most often associated with high risk HPV include:
- Cervical cancer in women
- Penile cancer in men
- Anal cancer in both sexes
- Oropharyngeal (throat) cancer in men and women
The development of precancer or cancer is very unlikely in most people infected with even high risk strains of HPV. Still, genital warts warrant evaluation and regular screening by a doctor to check for abnormal cells. HPV 16/18 vaccines can also help prevent cancer-causing infections.
Who is at Risk for Genital Warts?
Anyone who has skin-to-skin genital contact with a person infected with HPV 6, 11, 16 or 18 can develop genital warts. Risk factors for acquiring genital warts include:
- Multiple sex partners or a recent new partner
- Not using condoms during sex
- Having sex at an early age
- History of other STDs like herpes or chlamydia
- Suppressed immune system
- Smoking cigarettes or marijuana
About 1% of sexually active adults in the U.S. have visible genital warts, with a peak incidence in those under age 30. However, over 90% of genital HPV infections have no symptoms. Even silent infections can still be transmitted to partners.
Do Warts Go Away?
Left untreated, the majority of warts will eventually go away on their own through the body’s immune response. However, it can take weeks, months, or even years for warts to clear without treatment.
About 65-75% of common warts resolve spontaneously within two years. The weaker immune response in children means warts may persist longer. Plantar warts tend to be more stubborn, with only about 30% going away untreated after two years.
Genital warts from low risk HPV 6/11 also eventually regress in most patients. However, recurrence after clearing is common. Larger or spreading lesions may be treated by a doctor to speed recovery.
High risk genital warts have a lower spontaneous resolution rate. Since they can hide cancer-causing HPV, treatment is often warranted. Removing genital warts can help stimulate the immune system to keep cancer-linked HPV under control.
How to Get Rid of Warts
While many warts will go away on their own, various home remedies and medical treatments can remove warts faster. Methods for getting rid of common warts include:
Home Treatment
- Duct tape – Covering warts to occlude oxygen
- Salicylic acid – Chemicals to dissolve thick skin
- Freezing – Applying ice packs to freeze lesions
Medical Procedures
- Cryotherapy – Freezing warts with liquid nitrogen
- Laser therapy – Using lasers to burn off warts
- Electrocautery – Burning off warts with electric current
- Excision – Cutting out warts surgically
For genital warts, doctors often prescribe topical creams like imiquimod, podofilox, or sinecatechins to stimulate wart regression. Severe cases may necessitate surgical destruction or removal for clearance. Removing genital warts can help prevent recurrence and transmission to partners.
How to Prevent Warts
Preventing wart-causing HPV infection is not always possible. But measures like good hygiene, protection during sex, and vaccination can reduce risk:
- Avoid skin-to-skin contact with warts of others
- Use flip flops in showers/locker rooms
- Don’t share towels, razors, or other personal items
- Use condoms during sex
- Get vaccinated against HPV
- Don’t smoke or have multiple sex partners
- Boost immunity by reducing stress and eating right
Gardasil and Cervarix are vaccines that protect against wart-causing HPV strains 6 and 11, as well as cancer-linked types 16 and 18. The CDC recommends routine vaccination for girls and boys starting at ages 11-12. Catch-up shots can be given through age 26.
When to See a Doctor for Warts
Most common warts can be self-treated at home without a doctor’s intervention. See a physician if:
- Warts are widespread, painful, or spreading
- Lesions don’t respond to over-the-counter treatments
- Warts are pigmented, bleeding, or seem unusual
- Genital warts or lesions are present
- You have a weakened immune system
- Warts are interfering with function or quality of life
Doctors can prescribe stronger medications, perform procedures to remove warts, or take a biopsy to check for precancer or cancer. Leave treatment of genital warts to your physician.
Conclusion
HPV infection with certain strains can cause warts on various body parts. Genital warts are caused by sexually transmitted papillomavirus, making them an STD. However, common warts on hands, flat warts on the face, and plantar warts on feet are not sexually transmitted. Only genital warts are always classified as an STD. Although uncomfortable and embarrassing, most warts are harmless and resolve eventually without treatment. Practicing safe sex, good hygiene, and getting vaccinated are the best protections against wart-causing HPV infection.