Human Papillomavirus and Genital Warts, NIAID Fact Sheet: NIAID
Article title: Human Papillomavirus and Genital Warts, NIAID Fact Sheet: NIAID
Conditions: Human papillomavirus, genital warts
Human Papillomavirus and Genital Warts
What is human papillomavirus?
Human papillomavirus (HPV) is one of the most common causes of
sexually transmitted disease (STD) in the world. Health experts
estimate that there are more cases of genital HPV infection than of
any other STD in the United States. According to the American Social
Health Association, approximately 5.5 million new cases of sexually
transmitted HPV infections are reported every year. At least 20
million Americans are already infected.
Scientists have identified more than 100 types of HPV, most of
which are harmless. About 30 types are spread through sexual
contact. Some types of HPV that cause genital infections can also
cause cervical cancer and other genital cancers.Like many STDs,
genital HPV infections often do not have visible signs and symptoms.
One study sponsored by the National Institute of Allergy and
Infectious Diseases (NIAID) reported that almost half of the women
infected with HPV had no obvious symptoms. People who are infected
but who have no symptoms may not know they can transmit HPV to
others or that they can develop complications from the virus.
What are genital warts?
Genital warts (condylomata acuminata
or venereal warts) are the most easily recognized sign of genital
HPV infection. Many people, however, have a genital HPV infection
without genital warts.
Can HPV cause other kinds of warts?
Some types of HPV cause
common skin warts, such as those found on the hands and soles of the
feet. These types of HPV do not cause genital warts.
How are genital warts spread?
Genital warts are very
contagious and are spread during oral, genital, or anal sex with an
infected partner. About two-thirds of people who have sexual contact
with a partner with genital warts will develop warts, usually within
three months of contact.
In women, the warts occur on the
outside and inside of the vagina, on the opening (cervix) to the
womb (uterus), or around the anus. In men, genital warts are less
common. If 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.
Genital warts often occur in clusters and can be very tiny
or can spread into large masses in the genital or anal area.
How are genital warts diagnosed?
A doctor or other health
care worker usually can diagnose genital warts by seeing them on a
patient. Women with genital warts also should be examined for
possible HPV infection of the cervix.
The doctor may be able
to identify some otherwise invisible warts in the genital tissue by
applying vinegar (acetic acid) to areas of suspected infection. This
solution causes infected areas to whiten, which makes them more
visible, particularly if a procedure called colposcopy is performed.
During colposcopy, the doctor uses a magnifying instrument to look
at the vagina and cervix. In some cases, the doctor takes a small
piece of tissue from the cervix and examines it under the
A Pap smear test also may indicate the possible
presence of cervical HPV infection. In a Pap smear, a laboratory
worker examines cells scraped from the cervix under a microscope to
see if they are cancerous. If a woman’s Pap smear is abnormal, she
might have an HPV infection. If a woman has an abnormal Pap smear,
she should have her doctor examine her further to look for and treat
any cervical problems.
What is the treatment for genital warts?
Genital warts often
disappear even without treatment. In other cases, they eventually
may develop a fleshy, small raised growth that looks like
cauliflower. There is no way to predict whether the warts will grow
or disappear. Therefore, if you suspect you have genital warts, you
should be examined and treated, if necessary.
factors such as the size and location of the genital warts, a doctor
will offer you one of several ways to treat them.
- Imiquimod, an immune response cream which you can apply to the
- A 20 percent podophyllin anti-mitotic solution, which you can
apply to the affected area and later wash off
- A 0.5 percent podofilox solution, applied to the affected area
but shouldn’t be washed off
- A 5 percent 5-fluorouracil cream
- Trichloroacetic acid (TCA)
If you are pregnant, you
should not use podophyllin or podofilox because they are absorbed by
the skin and may cause birth defects in your baby. In addition, you
should not use 5-fluorouracil cream if you are expecting.
you have small warts, the doctor can remove them by freezing
(cryosurgery), burning (electrocautery), or laser treatment.
Occasionally, the doctor will have to use surgery to remove large
warts that have not responded to other treatment.
doctors use the antiviral drug alpha interferon, which they inject
directly into the warts, to treat warts that have returned after
removal by traditional means. The drug is expensive, however, and
does not reduce the rate that the genital warts
Although treatments can get rid of the warts, none
gets rid of the virus. Because the virus is still present in your
body, warts often come back after treatment.
How can HPV infection be prevented?
The only way you can prevent getting an HPV infection is to avoid
direct contact with the virus, which is transmitted by skin-to-skin
contact. If you or your sexual partner have warts that are visible
in the genital area, you should avoid any sexual contact until the
warts are treated. Studies have not confirmed that male latex
condoms prevent transmission of HPV itself, but results do suggest
that condom use may reduce the risk of developing diseases linked to
HPV, such as genital warts and cervical cancer.
Can HPV and genital warts cause
types of HPV can cause cervical cancer. Others, however, cause
cervical cancer and also are associated with vulvar cancer, anal
cancer, and cancer of the penis (a rare cancer).
infections do not progress to cervical cancer. If a woman does have
abnormal cervical cells, a Pap test will detect them. It is
particularly important for women who have abnormal cervical cells to
have regular pelvic exams and Pap tests so that they can be treated
early, if necessary. Pregnancy and
Genital warts may cause a number of
problems during pregnancy. Sometimes they get larger during
pregnancy, making it difficult to urinate. If the warts are in the
vagina, they can make the vagina less elastic and cause obstruction
Rarely, infants born to women with genital
warts develop warts in their throats (laryngeal papillomatosis).
Although uncommon, it is a potentially life-threatening condition
for the child, requiring frequent laser surgery to prevent
obstruction of the breathing passages. Research on the use of
interferon therapy in combination with laser surgery indicates that
this drug may show promise in slowing the course of the disease. .
What research is going on?
Scientists are doing research on
two types of HPV vaccines. One type would be used to prevent
infection or disease (warts or pre-cancerous tissue changes). The
other type would be used to treat cervical cancers. Researchers are
testing both types of vaccines in people.
Where can I get more information?American Social
P.O. Box 13827
Park, NC 27709
Toll-free: 1-877-HPV-5868 (1-877-478-5868) (2:00
p.m. to 7:00 p.m. ET)https://www.ashastd.org/National
1-800-4 CANCER (1-800-422-6237)https://cancernet.nci.nih.gov/
NIAID is a component of the National Institutes
of Health (NIH). NIAID supports basic and applied research to
prevent, diagnose, and treat infectious and immune-mediated
illnesses, including HIV/AIDS and other sexually transmitted
diseases, tuberculosis, malaria, autoimmune disorders, asthma and
allergies. NIH is an agency of the U.S. Department of Health and
Office of Communications
and Public Liaison
National Institute of Allergy and Infectious
National Institutes of Health
Bethesda, MD 20892
Public Health Service
U.S. Department of Health and