What are the Different Types of HPV Infections?

There are more than 100 types of HPV infections, and approximately 40 can be transmitted via sexual contact. Medical professionals typically group them into two categories: high risk and low risk. These viruses tend to infect mucous membranes as well as the skin. A patient’s symptoms and related conditions depend on the type of HPV infection he or she has. There is a vaccine available for many of the high-risk types of HPV infections, which are a known cause of cervical cancer in women and anal and penile cancer in men.

The majority of HPV infections are actually low risk, or harmless, and most people infected with them never experience any symptoms or complications. The high-risk types of the virus can be spread very easily during sex. In very rare cases, pregnant women can transmit HPV to their children during vaginal birth. It is believed that approximately half of all sexually active men and women have been infected with a type of HPV.

Low-risk types of HPV can cause genital and other kinds of warts, and high-risk types can cause cancer. These types are spread when an infected person rubs his or her skin against the skin of an uninfected individual. Transmission via anal and vaginal intercourse is typical, but transmission during oral sex is also possible.

Ninety percent of genital warts cases are caused by low-risk HPV infections. Warts are soft and flesh-colored growths that can appear on the genitals or anywhere else on the skin. In general, warts are harmless and often resolve on their own within two years. Genital warts cannot be cured but are usually treated with prescription medication.

Up to 70 percent of cases of cervical cancer are caused by high-risk HPV infections 16 and 18. This type of cancer develops slowly and is preceded by the highly treatable precancerous condition called dysplasia. If left untreated, cervical cancer can spread to the intestines, liver, and bladder.

The HPV vaccine is administered in three doses and prevents the most common types of the virus that cause genital warts and cervical cancer. The vaccine is effective for women between the ages of nine and 26, with 11- and 12-year-old girls as the primary targeted population. Men who are between nine and 26 years old can be vaccinated to prevent genital warts. The effectiveness of the vaccine depends on receiving all three doses prior to becoming sexually active.

Latex condoms provide only some protection against high-risk types of HPV infections. Getting the HPV vaccine can help prevent infection. Those who do not qualify or who cannot get the vaccine should consider limiting their number of sexual partners to reduce their risk of infection.