Warts can happen on any parts of the body. They are caused by the Human Papilloma Virus (HPV) that infects skin and mucosal cells. There are over 100 HPV strains so let’s count them off, HPV1, HPV2, HPV3, HPV4, HPV5… I’m kidding, we don’t have all day! Each HPV virus strain has the ability to infect and make a little bump on the skin called a wart. Luckily, in otherwise healthy people, they can eventually go away on their own, usually in 1-2 years. Sometimes, we need to help it along a little bit, as they can be quite persistent and annoying. The ultimate concern is that they might spread and infect nearby skin cells (aka more bumps will form in more places), and some HPV types can promote cancer.
Who can get infected with HPV?
Anyone. Even those who are vaccinated with the HPV vaccine. People with lower immune systems like those undergoing chemotherapy for cancer or those infected with HIV, if they get warts, tend to get more warts and they are more difficult to get rid of. It is spread usually through sexual contact or skin-to-skin or skin-to-fomite contact.
What strains do the HPV vaccine protect again?
There are 3 HPV vaccines are licensed by the US Food and Drug Administration (FDA):
- 9-valent HPV vaccine (Gardasil® 9, 9vHPV) – HPV 6, 11, 16, 18, 31, 33, 45, 52, 58
- Quadrivalent HPV vaccine (Gardasil®, 4vHPV) – HPV 6, 11, 16, 18
- Bivalent HPV vaccine (Cervarix®, 2vHPV) – HPV 16, 18
Even if someone received the HPV vaccine, they are maximally protected against only 9 strains of the HPV virus. And… we already said there are more than 100 strains of HPV virus (that we know of!). Thus, one can still be infected against many other strains which can still form a bump on the skin. Scientists and doctors decided to vaccinate against against these subtypes because HPV 6, 11 are the 2 which cause 90% of genital warts and HPV 16, 18 are the 2 which cause 80% of cervical cancer. The remainder subtypes in the Gardasil (9-valent vaccine) contain other HPV strains 31, 33, 45, 52, and 58 that are known to cause cervical cancer as well.
Children ages 11-12 through 26 are recommended to get vaccinated with the HPV vaccines above. (Vaccination can start at age 9). Gardasil has been shown to prevent HPV 6, 11, 16, 18-related cervical and genital disease in young, HPV-naive women between ages 16-26 years old. However, given that the first FDA approval of HPV vaccines, in this case for Gardasil in 2006, many people are still not vaccinated against these viruses. The assumption is that most humans by age 12 are already exposed to those specific HPV virus strains so there is no need to vaccinate after. Although there is only limited data, in recalcitrant cases of genital warts, not improved with treatments, HPV vaccine stimulated an immune response and cured these individuals.
How can I cure genital warts?
There are many options, depending on how many there are and how big they are… all of them will work eventually but take some time, usually I tell patients it can take up to 6 months to rid them all. Some get lucky and warts disappear within the first treatment, whereas others may require multiple combinations of the following treatments.
- Liquid nitrogen – if there are only a few, liquid nitrogen spray can be used to kill skin cells and HPV viruses with it; at -196 degrees Celsius, liquid nitrogen burns off warts. [I warn patients that there are bumps that we may not see today but may come up before the next treatment, as the virus may have already infected other skin but the skin did not form a bump yet.] Patients come back every 3-4 weeks for repeat treatment until all bumps are gone.
- Imiquimod 3.75% (Zyclara) or 5% cream (Aldara) – this is a cream applied to genital warts to stimulate your immune system to fight off the warts – it activates TLR7 which is part of the body’s innate immune system pathway and tells the body that there’s something it needs to start attacking.
- Podophyllin resin or podophyllotoxin – made from the May apple plant (Podophyllum peltatum Linne) containing the active ingredient podophyllotoxin which stops any cell that is dividing. There is a prescription version and a clinic version which is applied in the office by a doctor.
- Sinetachins / Polyphenon E (Veregan) – an ointment made of an extract from green tea (Camellia sinensis) which contains catechins, specifically something called epigallocatechin gallate, which fights against cancerous and virally infected cells.
- Quadrivalent or 9-valent vaccine – as mentioned above, limited studies show that vaccination can help clear recalcitrant cases of warts on the hands or genitals.
- Cimetidine – an antihistamine is believed to activate immune cells, specifically Th1 cells to produce anti-viral proteins such as IL-2, and IFN-c which will help the body get rid of warts .
- Photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) – this method uses ALA which will accumulate into abnormal tissues more so than normal tissues; once stimulated by blue light – it will selectively remove abnormal cells. Cost is a factor here as insurance may not cover this.
- Carbon dioxide laser or surgical techniques (ie. shave removal followed by electrocautery) – these methods get risk of warts by direct removal – however, there is a risk that the HPV virus may be released into the air with the potential risk of breathing the virus in causing respiratory papillomatosis (or HPV within breathing tubes) – thus is generally not recommended for safety of patients and providers.
What are some tips to avoid spreading the warts?
- Keep the hair – avoid shaving, waxing, or using depilatories as it can injure the skin and allow the HPV to continue infecting nearby skin.
- Limit friction – again, any injury to skin can spread the virus.
- Use condoms for any type of sex (oral, anal, vaginal) to prevent the spread.
- Treat your partners – partners can spread warts back and forth.
- Get regular pap smears – for women – routine pap smear can check for any atypical cells in the cervix which can help identify early signs of cancer.
Genital warts cause significant morbidity in the United States. Although there is no definitive treatment yet, all treatments will eventually work, it just takes some time. Hopefully, with the FDA approval of the 3 types of HPV vaccines, more and more children will get the vaccine thereby decreasing the incidence of both genital warts and HPV-related cancers such as cervical cancer, anal cancers, and oral cancers in the near future.
I am a board certified dermatologist based in Los Angeles. I am a comprehensive dermatologist caring for families. I love seeing children and adults. My youngest patient was 0 days old and her oldest was 110 years old. I have had psoriasis since the age of 8 and considered an expert in psoriasis and psoriasis treatments. I have lectured locally and nationally and published numerous papers on other topics such as skin manifestations of eczema, hidradenitis suppurativa, systemic lupus erythematous, granuloma annulare, microbiome, skin cancers, and more. My expertise includes knowledge in managing complex skin diseases. I am experienced with surgical treatment of skin cancers, as well as non-surgical methods to treat skin cancer and precancerous lesions. I run a full medical, cosmetic, and surgical dermatology practice. I am experienced with the use of complex dermatologic therapy, including biologic therapy, immunosuppressive medications, and phototherapy. I also treats fine lines and wrinkles non-surgically with combinations of botox, fillers, chemical peels, lasers, and radiofrequency. I perform minor surgeries such as excisions for cysts, lipomas, basal cell skin cancer, squamous cell skin cancers, and early stage melanoma. I am physician expert for Kopa for Psoriasis, part of Happify. I have been featured on podcasts and quoted in numerous online and print publications. I am honored to be named “Top Doctor” in Los Angeles magazine. In my free time, I volunteer for community events such as skin cancer screenings and at the local free clinics. I also teach internal medicine and dermatology residents at several academic centers. I try to do yoga every day and every year, I run a half-marathon at the Golden Gate Bridge.