Human papilloma virus (HPV)

Human Papilloma Virus (HPV) is a family of viruses. Certain types of HPV can cause common warts on the hands, feet and other parts of the body. Other types of HPV can cause genital warts as well as pre-cancerous and cancerous changes in the genital area and specifically the uterine cervix.



Other Names

 * HPV
 * Human Papilloma Virus

Related names include:

 * Cervical dysplasia
 * LGSIL
 * HGSIL
 * Cervical cancer
 * Genital warts

Types
There are more than 100 types of HPV that have been identified, of which about 30-40 are sexually transmitted and can cause genital infections.
 * “Low risk” types of genital HPV (such as types 6 and 11) can cause anogenital warts.
 * “High risk” types of HPV (such as types 16 and 18) can cause precancerous changes in the cervix which can progress to cervical cancer. In addition, “high risk” types of HPV can cause vaginal, vulvar and anal precancerous lesions and cancers.

Signs and Symptoms
It is estimated that about 75% of men and women have been exposed to the genital HPV viruses if they have ever been sexually active. The virus may lie dormant. The person may not know that they have the HPV virus and they may unknowingly infect another sexual partner later.

The HPV virus is contracted through sexual activity in skin-to-skin contact and not through bodily fluids. Condoms are helpful in preventing cervical cancer and cervical precancerous lesions, but they may not protect against genital warts.

A pap smear is the best way to find an HPV infection of the uterine cervix. If someone is infected with the low risk types of HPV, they may have genital warts.

Genital warts are firm bumps on the skin of the genital area. They are not tender. They are usually flesh colored or whitish in color. They may resemble warts on other parts of the body.

At this time, there is no routinely used test for a man to see if he has HPV. However, if the man had a prior sexual partner who had abnormal pap smears, dysplasia or cervical cancer, he has a higher chance of passing on a high risk type of HPV.

Diagnosis
Cervical HPV is diagnosed in women with a pap smear test. If a pap test is abnormal, a colposcopy may need to be performed to obtain direct biopsies of abnormal areas.

Genital warts are diagnosed either by a health care provider who visually looks at the warts and is able to recognize and treat them. A biopsy of the wart may be performed if the provider is uncertain.

Exams and tests

 * Pap smear:  A woman’s pelvic exam usually includes a pap smear.  A speculum is placed in the vagina to help the doctor see the uterine cervix.  A special soft brush and spatula device are used to collect cervical cells.  These are sent off to a special laboratory where the pathologist looks at the cells under a microscope to see if the cervical cells are normal or if there are signs of dysplasia (precancerous cells) or cancerous cells.


 * The value of the pap smear is the early detection of cancerous and precancerous lesions of the cervix when they are the most easily treated.

Fortunately, the pap test can pick up early precancerous lesions before they become cancerous.


 * HPV DNA Test:  There are currently two FDA-approved tests for the detection of HPV infection.  Using different methods, these tests are designed to detect the presence of HPV DNA of both high risk and low risk HPV subtypes in cervical cell samples.  These tests are usually done at the same time and on the same sample as the Pap smear.  The HPV DNA test, when used in conjunction with the Pap smear increases the likelihood of detection of cervical cancer or precancerous states to nearly 100%.


 * Colposcopy: A colposcope (lighted microscope on a stand) is used by the physician or health care provider to examine the vagina and cervix in women who had an abnormal pap smear.  Specifically, a speculum is placed in the vagina and then a dilute vinegar solution is used.  The dilute vinegar solution makes the abnormal cells appear whitish.  The physician takes biopsies of abnormal looking areas which are then examined in the lab by a pathologist.

Treatment
===Pap smear results and recommended treatment, ===


 * Atypical cells: If the HPV test is positive, the physician will usually recommend that the patient undergo a colposcopy test to make sure that there are no abnormal lesions on the cervix.


 * Low grade squamous intraepithelial lesion (also called LGSIL, LSIL, CIN I, low grade dysplasia): Early precancerous cervical cells of the cervix (LGSIL) will usually revert back to normal on their own because the woman’s immune system fights the virus. Seventy-five percent of the time, a young healthy woman’s immune system will rid the cervix of the HPV virus within two years.


 * High grade squamous intraepithelial lesion (also called HGSIL, HSIL, high grade dysplasia, CIN II, CIN III or carcinoma in-situ of the cervix): These more advanced types of precancerous cells should be treated so that they do not become cancerous.  Treatment usually is done by either a procedure called a LEEP (Loop Electrocautery Excision Procedure) or a cone biopsy of the cervix.

If it is uncertain if a patient has a high grade dysplasia versus an early cervical cancer, a cone biopsy of the cervix is usually performed.

Genital Warts
Genital warts are generally treated by a health care provider with liquid nitrogen or with a strong acid to burn off the wart. Medications to be used at home include Aldara cream. This cream is applied at night three times a week for at least six weeks.

Prevention
To reduce the risk of HPV-related disease, individuals can:
 * use condoms to decrease skin-to-skin contact and hence reduce (but not eliminate) the risk of HPV transmission.
 * get regular pap smears which may detect HPV disease before it progresses.
 * receive the HPV vaccine which protects against subsequent infection by vaccine-type HPV.

HPV vaccines
In 2006, Merck released a vaccine against genital HPV called Gardasil. The vaccine protects against the two high risk HPVs (HPV 16 and 18) that cause 70% of cervical cancers. The same vaccine also protects against HPV 6 and 11 which cause 90% of genital warts. The vaccine is approved for girls and women ages 9 to 26 years old.

If a girl or woman is vaccinated against HPV with the Gardasil vaccine, she still will need to get regular pap smears when she becomes sexually active. Pap smears can pick up abnormalities in the cervix early before they become cancerous.

Even if a girl received Gardasil before she became sexually active, Gardasil is effective in preventing the HPV that causes 70% of cervical cancer and 90% of genital warts. A woman could still get cervical cancer or precancerous changes from other high risk types of HPV besides 16 and 18. Therefore, it is very important to get routine pap smears as directed by her healthcare provider.

HPV vaccine: Gardasil vaccine FAQs

HPV vaccine: HPV Vaccine Facts

In addition, GlaxoSmithKline manufacturers a vaccine against HPV types 16 and 18 called Cervarix. This has been licensed in the European Union but approval in the United States is still pending.

Risk factors
Most women will be infected with HPV at sometime in their life. However, few will get cervical cancer.

Women have a higher chance of getting cervical cancer if they:
 * Smoke
 * Have HIV or AIDS
 * Have a weak immune system because of medications (such as transplant medications)
 * Have an aggressive, high risk type of HPV infection
 * Have multiple sex partners
 * Do not have regular pap smears

Clinical Trials
Open Clinical Trials for HPV disease

History
The pap smear is named after pathologist Georgios Papanikolaou. Initially, Dr. Papanikolaou was testing a theory about hormonal effects on vaginal cells. He took smears of vaginal fluid near the cervix. One of his study patients had cervical cancer and the cancer cells were seen on a slide that Papanikolaou had prepared. His work was not recognized in the medical community until years later when he published a paper in 1941 with gynecologist Dr. Herbert Traut on the early detection of uterine cancer by the vaginal smear.

Related Videos
This video from the NIH provides the latest on cervical cancer, including screening with pap tests, and the HPV vaccine.