Human papillomavirus (HPV) is a hot topic these days thanks to the advent — and attendant controversy — of Gardasil, the vaccine that protects against four strains of this sexually transmitted virus. Discourse centers around HPV-16 and HPV-18, the two HPV strains that together are responsible for 70 percent of cervical cancers and 90 percent of anal cancers. However, Gardasil also protects against HPV-6 and HPV-11, two HPV strains that aren’t associated with cancer but rather with 90 percent of genital warts. While genital warts don’t have the potential to cause cancer and death, they can be very upsetting to the people who develop them.

Every year in the United States, about $200 million is spent to treat genital warts.

Many strains of human papillomavirus can cause warts, and not all of them are sexually transmitted. For instance, HPV-1, HPV-2, and HPV-4 cause warts on the hands and feet and are spread by skin-to-skin contact. About 40 strains of HPV can be transmitted sexually — they are called “mucosal” strains because of their affinity for mucous membranes such as the skin found in the genital, anal, and oral regions. Ninety percent of cases of genital warts are caused by two strains of HPV: HPV-6 and HPV-11. Genital warts are highly contagious and can be transmitted by any type of sexual activity.

Let’s start with a quick overview of genital warts. While it’s quite possible for someone infected with a wart-causing strain of HPV to be completely asymptomatic, the physical appearance of warts can take several forms. They can appear in the genital area, in or around the anus, and (very rarely) in the mouth, lips, palate, or throat. They can also rarely be found on the cervix and vaginal walls. They are soft to the touch and can be raised, flat, or bumpy. They may or may not be itchy or painful. Genital warts can be small or quite large. As you can see, there are a wide variety of ways they can manifest themselves, despite being caused by one type of virus. There are four types:

condylomata acuminata , which have a “cauliflower-like” appearance

, which have a “cauliflower-like” appearance papular warts , which are dome-shaped papules 1-4 millimeters in diameter

, which are dome-shaped papules 1-4 millimeters in diameter keratotic warts , which have a thick, “crust-like” layer

, which have a thick, “crust-like” layer flat-topped papules, which can look like a freckle or might be slightly raised from the surface of the skin

Genital warts usually develop within six weeks to six months after exposure, but could take longer to appear. If our immune systems are healthy, our bodies may be able to fight off the virus — our immune systems are normally able to clear 90 percent of genital-wart infections within two years of exposure. Unfortunately, if the immune system can’t fight off the virus, the infection will become chronic, in which case warts can resurface throughout one’s lifetime. The warts can be removed by a doctor, but you could still transmit the virus to others and you might experience a recurrence of the warts. Smokers’ immune systems are less likely to be able to fight off the infection, and in the case of a chronic infection, smokers’ warts are more likely to return even after being removed by a health care provider.

You can reduce your risk of acquiring HPV by consistently and correctly using condoms and dental dams. The female condom (also known as the receptive condom, the internal condom, or the insertive condom) is more effective in protecting against HPV transmission because it covers more surface area than regular condoms. However, barrier methods are limited by how much of the skin’s surface they can cover. Because the virus can reside in skill cells that aren’t covered by a condom or dental dam, HPV can still be spread even when safer-sex methods are used. Aside from total abstinence, the best protection against genital warts is to be vaccinated with Gardasil before becoming sexually active. (If you are already sexually active, you still could benefit from the vaccine. Talk to a health care provider for advice.)

Genital warts by themselves are not life-threatening, though they can cause bleeding; when open wounds are present, the risk for the transmission of other STDs increases. Warts can also cause emotional distress, so most people who have them want to find ways to get rid of them. Old folk remedies included strategies such as rubbing a dead toad on the warts; these days there are many effective ways of getting rid of them, including surgical and nonsurgical methods. Talk to a health care provider to find out which option is best for you. They are easier to treat if therapy is sought within the first year of their appearance. Unfortunately, each treatment can cost several hundred dollars and the warts could return in the future (annually, about $200 million is spent to treat genital warts in the United States alone). Furthermore, evidence shows that warts can still be transmitted even when they have been removed because viruses can lurk in the surrounding skin cells. It is possible, however, that the removal of warts makes transmission less likely — but right now researchers don’t know for sure.

Genital warts could pose a problem during pregnancy. Hormonal changes can induce the warts to grow in size, and transmission to the infant during childbirth is possible, though rare. A congenital infection can lead to the growth of warts in the respiratory tract. This infection is called recurrent respiratory papillomatosis, and it can cause breathing problems. The warts can be removed, but they will usually keep growing back. This is a rare condition — only 1 in 200,000 children develops it — but it’s one more reason to consider Gardasil and always to use barrier methods during sexual activity.

Planned Parenthood health centers, as well as other clinics and health-care providers, can diagnose and treat genital warts. Additionally, Planned Parenthood carries Gardasil, the vaccine that protects against the strains of HPV responsible for 90 percent of genital warts.

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