Genitourinary Diseases: Human Papilloma Virus (HPV)
Human Papilloma Virus (HPV)
Background
- Causative Agent: Human Papilloma Virus
- Over 100 different types.
- Infects mucosal surfaces such as the cervix, vagina, urethra, and penis.
- 40 different types are considered "high risk".
Epidemiology
- Most common STD in the U.S. (linked to the number of partners).
- Linked to 99% of cervical cancer cases worldwide.
- On average, 12,000 women are diagnosed with cervical cancer each year in the U.S. (with women of color disproportionately affected).
- Approximately 4,000 women die each year from cervical cancer.
Transmission
- Direct Contact:
- Skin-to-skin contact.
- Anal, vaginal, and oral sex, primarily sexual intercourse.
Symptoms and Clearance
- The majority of women clear HPV infections within 2 years.
- Symptoms:
- Abnormal vaginal bleeding.
- Pain during intercourse.
- Bleeding after intercourse.
Types of HPV
- Low Risk (Non-Oncogenic):
- HPV-6 and HPV-11: Cause genital warts.
- High Risk (Oncogenic):
- HPV-16 (more carcinogenic) and HPV-18: Linked to 70% of cervical cancer cases.
- Can cause cancer of the cervix, penis, anus, or vulva.
Genital Warts
- Non-cancerous, irregular growths that resemble cauliflower.
- HPV-6 and HPV-11 cause 90% of cases.
Pathogenesis: Cervical Cancer
- Virus produces E6 and E7 proteins.
- These proteins bind to and inactivate p53.
- p53: Tumor suppressor gene.
Function of p53 (Tumor Suppressor Gene)
- Cell Cycle: Consists of a "prep" stage called Interphase.
- Detects genetic mistakes made during the G1 phase of the cell cycle.
- Arrests cell growth during cell division.
Prevention
- Pap Smears: Important screening tool, starting at age 21.
- Cells for Pap smears are collected from the cervix.
- At age 30 and up: Regular Pap smears in conjunction with HPV DNA test using PCR (every 5 years).
Current Events
- Current "epidemic" of oral warts, oral cancer, and throat cancer.
- HPV can infect oral mucous membranes.
Additional Prevention Methods
- Use condoms as ONE preventative measure.
- See your gynecologist regularly.
HPV Vaccine (GARDASIL)
- 9-valent vaccine, recently approved in 2014.
- Inactivated (non-infectious) viral particles that stimulate an immune response
- Recommended for both males and females to prevent HPV infection and associated cancers and genital warts.
- Ideal age for vaccination is before the start of sexual activity.
- Insurance coverage varies by age; consult with healthcare provider and insurance company for specific details.