Human papillomavirus (HPV) is the virus that causes warts and is the most common sexually transmitted infection worldwide. There are over 100 types of HPV, with some high-risk types causing cervical cancer and other cancers. HPV is spread through sexual contact and can cause genital warts or cervical dysplasia. While there is no cure for HPV infection, vaccination and treatment of symptoms can help prevent cancers caused by high-risk strains.

1. HUMAN PAPILLOMAHUMAN PAPILLOMA
VIRUSVIRUS
(HPV)(HPV)
SAM DICKSON ASEHSAM DICKSON ASEH
SELENKEH NISSISHALOMSELENKEH NISSISHALOM

2. HUMAN PAPILLOMA VIRUSHUMAN PAPILLOMA VIRUS
• HPV is the virus that causes warts.HPV is the virus that causes warts.
• Nonenveloped virus with icosahedralNonenveloped virus with icosahedral
nucleocapsid and circularnucleocapsid and circular
double-stranded DNAdouble-stranded DNA
• More than 100 different kinds, 30-some ofMore than 100 different kinds, 30-some of
this cause genital HPV.this cause genital HPV.
• Spread by sexual contact or from mother toSpread by sexual contact or from mother to
baby.baby.
• Genital warts appear 6 weeks to 8 monthsGenital warts appear 6 weeks to 8 months
after contact with an HPV infected person.after contact with an HPV infected person.

4. HPVHPV
• The most common sexually transmittedThe most common sexually transmitted
disease worldwide.disease worldwide.
• Certain types of HPV are linked withCertain types of HPV are linked with
cervical cancer.cervical cancer.
• Divided into 2 subcategories: GenitalDivided into 2 subcategories: Genital
Warts and Cervical Dysplasia.Warts and Cervical Dysplasia.
• Most people do not know they have it.Most people do not know they have it.
• There are high risk and low risk types of it.There are high risk and low risk types of it.

5. HISTORYHISTORY
• The papillomaviruses are part of theThe papillomaviruses are part of the
PAPOVAVIRIDAE family of DNA tumorPAPOVAVIRIDAE family of DNA tumor
viruses.viruses.
• First discovered in the early 40’s.First discovered in the early 40’s.
• Gained notoriety in the early 80’s when itGained notoriety in the early 80’s when it
was discovered that some types of HPVwas discovered that some types of HPV
caused cervical cancer.caused cervical cancer.

6. APPEARANCEAPPEARANCE

7. MECHANISM OF INFECTIONMECHANISM OF INFECTION
• All PV exhibit extreme specificity forAll PV exhibit extreme specificity for
infection on epithelial cells.infection on epithelial cells.
• The infection normally results inThe infection normally results in
hyperproliferation of the host cell and mayhyperproliferation of the host cell and may
lead to transformation.lead to transformation.

8. GENITAL WARTSGENITAL WARTS
• Sometimes called condylomataSometimes called condylomata
acuminata.acuminata.
• Are soft, moist or flesh colored, andAre soft, moist or flesh colored, and
appear in the genital area within weeks orappear in the genital area within weeks or
months after infection.months after infection.
• Sometimes appear in clusters and areSometimes appear in clusters and are
either raised or flat, small or large.either raised or flat, small or large.
• Women: appear in the vulva, cervix,Women: appear in the vulva, cervix,
vagina and anus.vagina and anus.
• Men: Can appear on the scrotum or penis.Men: Can appear on the scrotum or penis.

9. HPV TYPESHPV TYPES
• Numbered in order of discovery.Numbered in order of discovery.
• 30 HPV types primarily infect the squamous epithelium30 HPV types primarily infect the squamous epithelium
of the lower anogenital tracts of both males and females.of the lower anogenital tracts of both males and females.
• HPV types 6, 11, 42, 43, or 44 present as papillaryHPV types 6, 11, 42, 43, or 44 present as papillary
condylomas, may also present as flat lesions that may orcondylomas, may also present as flat lesions that may or
may not be visible to the unaided eye are part of themay not be visible to the unaided eye are part of the
“low-risk” HPV types.“low-risk” HPV types.
• Types 16, 18, 31, 33, 35, 45, 51, 52, and 56 areTypes 16, 18, 31, 33, 35, 45, 51, 52, and 56 are
considered “high-risk” types because they have beenconsidered “high-risk” types because they have been
found in cervical and other lower genital tract cancers.found in cervical and other lower genital tract cancers.

10. HOW HPV CAUSES CANCERHOW HPV CAUSES CANCER
• HPV DNA integrates into the host genome.HPV DNA integrates into the host genome.
• The proteins E6 and E7 are produced from the resultant DNA.The proteins E6 and E7 are produced from the resultant DNA.
• E6 binds and degrades p53 (a tumor suppressor gene).E6 binds and degrades p53 (a tumor suppressor gene).
• If the DNA is altered, the cell keeps replicating. The mutation rate ofIf the DNA is altered, the cell keeps replicating. The mutation rate of
the cell increases.the cell increases.
• E7 binds and degrades retinoblastoma (another tumor suppressorE7 binds and degrades retinoblastoma (another tumor suppressor
gene).gene).
• Retinoblastoma normally keeps the cell from growing too fast orRetinoblastoma normally keeps the cell from growing too fast or
responding to growth stimulators. This inhibitory factor is now lost.responding to growth stimulators. This inhibitory factor is now lost.
• without these two mechanisms to slow down cell growth andwithout these two mechanisms to slow down cell growth and
prevent mutation. . .prevent mutation. . .
• Malignant Transformation Occurs.Malignant Transformation Occurs.

11. HPV TREATMENTHPV TREATMENT
• Genital warts can be treatedGenital warts can be treated
by a doctor and by differentby a doctor and by different
methods.methods.
• Podofilox gel:Podofilox gel: A patient-A patient-
applied treatment for externalapplied treatment for external
genital warts.genital warts.
• Imiquimod cream:Imiquimod cream: AA
patient-applied treatment.patient-applied treatment.
• Chemical treatments (includingChemical treatments (including
trichloracetic acid andtrichloracetic acid and
podophyllin), which must bepodophyllin), which must be
applied by a trained healthapplied by a trained health
care provider to destroy warts.care provider to destroy warts.
• Cryotherapy:Cryotherapy: Uses liquidUses liquid
nitrogen to freeze off the warts.nitrogen to freeze off the warts.
• Laser therapy:Laser therapy: Uses a laserUses a laser
beam or intense lights tobeam or intense lights to
destroy the warts.destroy the warts.
• Electrosurgery:Electrosurgery: Uses andUses and
electric current to burn off theelectric current to burn off the
warts.warts.
• Surgery:Surgery: Can cut away theCan cut away the
wart in one office visit .wart in one office visit .
• Interferon:Interferon: an antiviral drug,an antiviral drug,
which can be injected directlywhich can be injected directly
into warts.into warts.

12. HPV VACCINEHPV VACCINE
• Vaccine is commonly called GardasilVaccine is commonly called Gardasil
• It is given in 3 separate injections over theIt is given in 3 separate injections over the
course of 6 months.course of 6 months.
• It protects against four types of HPVIt protects against four types of HPV
– two that cause 70 percent of all cervicaltwo that cause 70 percent of all cervical
cancercancer
– two that cause 90 percent of all genital warts.two that cause 90 percent of all genital warts.

13. CURECURE
• There is currently no cure for humanThere is currently no cure for human
papillomavirus.papillomavirus.
• Once an individual is infected, he or sheOnce an individual is infected, he or she
carries the virus for life even if genitalcarries the virus for life even if genital
warts are removed.warts are removed.
• If left untreated, some genital warts mayIf left untreated, some genital warts may
regress on their own.regress on their own.

14. CONCLUSIONCONCLUSION

15. SOURCESSOURCES
• http://cinvestav.mx/genetica/MyFiles/Papillhttp://cinvestav.mx/genetica/MyFiles/Papill
omavirus/PAPepi.htmlomavirus/PAPepi.html
• http://www.life.umd.edu/classroom/bsci42http://www.life.umd.edu/classroom/bsci42
4/BSCI223WebSiteFiles/LectureList.htm#4/BSCI223WebSiteFiles/LectureList.htm#
LecureListLecureList
• WWW.STDSERVICES.ON.NET/STD/WAWWW.STDSERVICES.ON.NET/STD/WA
RTSRTS
• Review of medical microbiologyReview of medical microbiology

16. THANK YOUTHANK YOU