Genital warts overview

# Overview
Genital warts is a highly contagious sexually transmitted infection caused by some sub-types of human papillomavirus (HPV). It is spread through direct skin-to-skin contact during oral, genital, or anal sex with an infected partner.

# Pathophysiology
Genital warts are the most easily recognized sign of genital HPV infection. They can be caused by strains 6, 11, 30, 42, 43, 44, 45, 51, 52 and 54 of genital HPV; types 6 and 11 are responsible for 90% of genital warts cases. Most people who acquire those strains never develop warts or any other symptoms. HPV also causes many cases of cervical cancer; types 16 and 18 account for 70% of cases; however, the strains of HPV that cause genital warts are not linked to the strains that cause cancer.

# Epidemiology and Demographics
Although treatments can remove the warts, they do not remove the HPV virus, so warts can recur after treatment. Traditional theories postulated that the virus remained in the body for a lifetime. However, new studies using sensitive DNA techniques have shown that through immunological response the virus can either be cleared or suppressed to levels below what PCR tests can measure. According to the Center for Disease Control's report on HPV to Congress in 2004, studies have shown that 70% of new HPV infections clear within one year, and as many as 91% clear within two years. The median duration of new infections is typically eight months. The gradual development of an effective immune response is thought to be the likely mechanism for HPV DNA clearance.

# Risk Factors
The state of the immune system determines the chances of removing the virus entirely and can be affected by factors such as HIV infection, certain medications, stress, or illness. There is even some suggestion that effective treatment of the wart may aid the body's immune response.

# Diagnosis

## History and Symptoms
Genital warts often occur in clusters and can be very tiny or can spread into large masses in the genital or penis area. In women they occur on the outside and inside of the vagina, on the opening (cervix) to the womb (uterus), or around the anus. They are approximately as prevalent in men, but the symptoms may be less obvious. When present, they usually are seen on the tip of the penis. They also may be found on the shaft of the penis, on the scrotum, or around the anus. Rarely, genital warts also can develop in the mouth or throat of a person who has had oral sex with an infected person.

# Treatment

## Medical Therapy
Genital warts may disappear without treatment, but sometimes eventually develop a fleshy, small raised growth. There is no way to predict whether they will grow or disappear.

## Surgery
Small warts can be removed by freezing (cryosurgery), burning (electrocautery), or laser treatment. Surgery is occasionally used to remove large warts that have not responded to other treatment.

## Primary Prevention
Gardasil (sold by Merck & Co.) is a vaccine that protects against human papillomavirus types 16, 18, 6, and 11. Types 6 and 11 cause genital warts, while 16 and 18 cause cervical cancer.  The vaccine is preventive, not therapeutic, and must be given before exposure to the virus type to be effective, ideally before the beginning of sexual activity.  The vaccine is widely approved for use by young women, it is being tested for young men, and has been approved for males in some areas, such as the UK.