HPV types 6 and 11 cause genital warts. These two strains are responsible for more than 90% of all cases. They belong to the “low-risk” category of HPV, meaning they rarely lead to cancer, though they can cause visible, sometimes persistent growths in the genital and anal areas.
Low-Risk vs. High-Risk HPV Types
There are dozens of sexually transmitted HPV types, and they fall into two broad groups: low-risk and high-risk. HPV 6 and 11 are the primary low-risk types. They cause warts but almost never cause cancer. This is an important distinction because many people hear “HPV” and immediately think of cervical or other cancers.
High-risk types are a different set entirely. There are 12 of them, with HPV 16 and 18 being the most significant. HPV 16 alone causes about 50% of cervical cancers worldwide, and together with HPV 18, it accounts for roughly two-thirds. These high-risk strains can also cause cancers of the anus, throat, vulva, vagina, and penis. They typically do not cause visible warts, which is part of what makes them dangerous: they often produce no obvious symptoms while slowly driving cell changes that can become cancerous over years.
So if you’ve been diagnosed with genital warts, the underlying infection is almost certainly a low-risk type. Having genital warts does not mean you have one of the cancer-causing strains, though it is possible to be infected with more than one HPV type at the same time.
How HPV 6 and 11 Cause Warts
The virus enters skin cells through tiny breaks or micro-abrasions in the genital area, the kind that naturally occur during sexual contact. It targets cells in the deepest layer of the skin called basal keratinocytes. Once inside, the virus copies its DNA and quietly maintains itself as the skin cell divides, keeping a low profile with minimal gene activity.
The wart forms when the infected cell moves into the outer layers of skin where cells normally stop dividing and begin to mature. At that point, the virus ramps up dramatically, producing thousands of copies of itself and driving the excess cell growth that creates the visible bump. This is why warts are essentially an overgrowth of skin cells hijacked by the virus.
What Genital Warts Look Like
Genital warts usually appear as small, flesh-colored bumps in the genital or anal area. They can show up as a single bump or a cluster. Some are flat and smooth, while others have a rough, raised texture that resembles cauliflower. They’re generally painless, though some people experience mild itching.
They can appear on the vulva, vagina, cervix, penis, scrotum, groin, thighs, or around the anus. Size varies widely. Some are barely visible, while clusters can grow larger if left untreated.
How Long They Take to Appear
After exposure to HPV 6 or 11, warts can take anywhere from a few weeks to several months to show up. This long, unpredictable incubation period makes it difficult to pinpoint exactly when or from whom you contracted the virus. Some people carry the infection and never develop visible warts at all, while others may see warts appear months after their last sexual contact.
It’s also possible to transmit the virus even when no warts are visible. HPV spreads through skin-to-skin contact during vaginal, anal, or other close genital contact. How long someone remains contagious after warts clear is not well understood.
Diagnosis
Most genital warts are diagnosed by visual examination alone. A healthcare provider can typically identify them based on their appearance and location. In some cases, a dilute acetic acid (vinegar) solution is applied to the skin, which turns HPV-affected areas white and makes subtle or flat lesions easier to spot. This technique has limitations, though. Skin irritation and eczema can also turn white with acetic acid, so the test works best when combined with close visual assessment and, sometimes, a biopsy to confirm.
HPV testing for the specific type (6, 11, etc.) is not routinely performed for genital warts. The visual diagnosis is usually sufficient, and knowing the exact strain rarely changes treatment.
Treatment Options
Genital warts often clear on their own as the immune system suppresses the virus, but many people choose treatment to remove visible warts faster or reduce discomfort. Treatment removes the wart tissue itself. It does not eliminate the underlying HPV infection, which your immune system handles over time.
There are two broad approaches: topical treatments you apply at home, and procedures performed in a clinic.
At-Home Topical Treatments
Several prescription creams and solutions can be applied directly to warts. One common option works by stimulating your local immune response against the virus, applied three times per week at bedtime for up to 16 weeks. Another is a plant-based solution applied twice daily for three days, followed by four days off, repeated for up to four cycles. A third option is a green tea extract ointment applied three times daily until warts clear, for up to 16 weeks. Each has different application routines and side effects, and your provider will recommend one based on the number, size, and location of your warts.
Clinical Procedures
For larger or more stubborn warts, a provider may use cryotherapy (freezing the wart with liquid nitrogen) or laser treatment. Cryotherapy clears warts in roughly 79 to 88% of cases. Laser treatment has similar success rates. In a head-to-head comparison, both methods achieved nearly identical clearance and both carried a recurrence rate of about 22 to 24%. The choice between them often comes down to availability and provider preference. Surgical excision is another option for very large warts.
Regardless of method, recurrence is common. Warts can come back weeks or months after treatment because the virus may persist in surrounding skin even after the visible wart is gone.
Vaccination Prevents Most Cases
The HPV vaccine (Gardasil 9) protects against nine HPV types, including types 6 and 11. It is highly effective: among vaccinated teen girls, infections with the HPV types responsible for most genital warts and HPV-related cancers dropped by 88%. Among young adult women, the reduction was 81%.
The vaccine is recommended for everyone starting at age 11 or 12, though it can be given as early as age 9 and is approved for adults through age 45. It works best when given before any exposure to the virus, but even people who have already had one HPV type can benefit from protection against the others covered by the vaccine. If you’ve already been diagnosed with genital warts caused by type 6, for example, the vaccine could still protect you against type 11 and the seven high-risk cancer-causing strains it covers.