2. WHAT IS HPV?
• HPV stands for human papillomavirus. There
are lots of different types of HPV.
• Genital HPV is a very common sexually
transmitted infection. No symptoms
• More than 100 types
– More than 60 cutaneous types
• Can lead to skin warts
– 40 mucosal types
• High risk – most common are HPV 16, 18,
45 and 31.
• Low risk- include HPV types 6, 11.
Cause ~70% of
cervical cancersCause ~ 90% of
anogenital warts
3. How many people are infected?
• Genital HPV infections are very common among
sexually active individuals.
• At any time, about 20 million people have a genital
HPV infection.
• 74 percent of new infections occur among young
people age 15–24
4. How HVP looks like?
• Papillomaviruses are small, 52-55nm in
diameter.
• They are non-enveloped, icosahedra
particles.
• This shape is made up of 12 pentameric
and 60 hexameric capsomers arranged on
a T=7 lattice.
• Their carpsid is composed of two
proteins, a major (L1) and minor (L2).
5. HPV Transmission
• Direct skin-to-skin contact
– Usually, but not always sexual contact
• Infected birth canal
• Fomites (very rare)
6.
7. Testing & Treatment for
Genital Warts
• Can be detected in a clinical
exam;
– History
– Visual exam
– Pap smears
– DNA testing
• Can be treated by removing the
warts;
• The virus cannot be removed, so
the warts may grow back.
8. Human Papilloma Virus (HPV) Vaccine
Two vaccines currently developed:
1. Gardasil – protects against HPV types 16, 18,
6 and 11.
2. Cervarix – protects against HPV types 16 and
18.
Notas do Editor
There are more than 100 types of HPV. About 30-40 types can infect the genital area-vulva, vagina, cervix, rectum, anus, penis and scrotum. Some types cause genital warts, some cause changes in cells (cervix). Most types seem to have no harmful effect at all.
Some studies estimate that the majority of the sexually active population is exposed to at least one or more types of HPV-although most do not develop symptoms. Because HPV is so common and prevalent, a person does not need to have a lot of sex partners to come into contact with this virus.
According to the Centers for Disease Control and Prevention, there are approximately 6.2 million new cases of HPV infections reported each year. It is estimated that 20 million persons are currently infected after becoming sexually active and approximately 80 million persons between the ages of 15-24 have been infected with some type of HPV at one point in their life.
Papillomaviruses are small, approximately 52-55nm in diameter.
They are non-enveloped, icosahedra particles. This shape is made up of 12 pentameric and 60 hexameric capsomers arranged on a T=7 lattice.
Their carpsid is composed of two proteins, a major (L1) and minor (L2).
As is the case with warts on other parts of the body, direct skin-to-skin contact spreads HPV most easily because HPV lives primarily in the skin and mucosal cells and is not transmitted via blood or body fluids.
Genital papillomavirus is transmitted through:
1) sexual contact (genital tract HPV)
2) during passage through an infected birth canal (Discuss in more depth tomorrow)
3) fomites (rare) Fomites are inanimate objects that may harbor the infectious organism and transmit it when the fomite is introduced to a non-infected person. Some experts believe that in rare cases HPV may be transmitted through shared bath towels, for example
Your health care provider can usually tell if you have genital warts because he/she can see them. Sometimes they may be so small that your health care provider might put a vinegar type solution on the wart and use a magnifying glass or microscope to see the wart.
A Pap smear is the best way to detect cervical changes due to HPV.
Although the Pap is not a specific test for HPV, the Pap test can detect abnormal cells associated with HPV before they become cancerous. Identification can lead to early treatment and can preserve life and fertility.
DNA TESTING is too expensive to be used as a screening tool. However, it has been used successfully to identify types of HPV in certain lesions and cancers, and has been valuable in choosing treatment type.
A biopsy is only necessary if the wart is unusual looking or discolored.
There are currently no blood tests available.