What are the differences in prevention and treatment between Human Papillomavirus (HPV) and genital herpes?

HPV vs Genital Herpes: Key Differences in Prevention and Treatment

The fundamental difference is that HPV can be prevented with highly effective vaccination before exposure, while genital herpes has no vaccine and requires lifelong antiviral management once infected. 1

Prevention Strategies

HPV Prevention

• Vaccination is the cornerstone of HPV prevention, with routine immunization recommended for all males and females aged 11-12 years (can start as early as age 9) 1
• The nonavalent vaccine (9vHPV) prevents approximately 90% of cervical and other HPV-related cancers by protecting against HPV types 6,11,16,18,31,33,45,52, and 58 1
• Catch-up vaccination is recommended for females through age 26 and males through age 21 (through age 26 for MSM and immunocompromised persons) 1
• Condom use reduces HPV infection risk by approximately 70% when used consistently and correctly 1
• Complete sexual abstinence is the only way to completely prevent genital HPV infection 1
• For sexually active individuals, monogamous relationships with uninfected partners reduce future infection risk 1

Genital Herpes Prevention

• No vaccine exists for HSV prevention 2
• Suppressive antiviral therapy (valacyclovir 500 mg twice daily) in infected partners reduces transmission to serodiscordant partners 3, 4
• Condom use during all sexual exposures with new or uninfected partners reduces transmission risk 4
• Avoiding sexual contact when lesions or prodromal symptoms are present is essential 4
• Critical caveat: Asymptomatic viral shedding occurs frequently and accounts for the majority of HSV transmission, even when no symptoms are present 3, 2

Screening Approaches

HPV Screening

• All women should have Pap test screening within 3 years of sexual activity or by age 21 years, whichever comes first 1
• Women aged >30 years with three consecutive normal Pap tests should be screened every 2-3 years 1
• HPV testing as adjunct to Pap testing may be appropriate in certain populations 1
• Screening interval can increase to 3 years if both Pap and HPV testing are negative in women >30 years 1

Genital Herpes Screening

• Routine serologic screening is NOT recommended in asymptomatic individuals with low pretest probability 4, 2
• Type-specific serologic testing should be performed in persons with genital symptoms consistent with herpes to establish diagnosis 4
• Screening is not recommended for pregnant women without symptoms 4

Treatment Differences

HPV Treatment

• HPV infections themselves are not treated; only HPV-associated lesions are managed 3
• Treatment options for cervical, vaginal, and vulvar precursors include cryotherapy, electrocautery, laser therapy, and surgical excision 1
• Genital warts can be treated with topical pharmacologic agents including imiquimod 3.75% cream 1
• Important limitation: Available therapies may reduce but probably do not eliminate infectiousness 3
• Approximately 20-30% of anogenital warts regress spontaneously, but recurrence is common (approximately 30%) 3

Genital Herpes Treatment

First Clinical Episode

• Treat with valacyclovir 1 g orally twice daily, acyclovir 400 mg orally three times daily, or famciclovir 250 mg orally three times daily for 7-10 days 4
• Treatment may be extended if healing is incomplete after 10 days 4

Recurrent Episodes (Episodic Therapy)

• Valacyclovir 500 mg orally twice daily, acyclovir 400 mg orally three times daily, or famciclovir 125 mg orally twice daily for 5 days 4
• Episodic therapy is most effective when started during prodrome or within 1 day after lesion onset 4
• Treatment initiated >24 hours after symptom onset has limited effectiveness 5

Suppressive Therapy

• Daily suppressive therapy with valacyclovir 1 g orally once daily, acyclovir 400 mg orally twice daily, or famciclovir 250 mg orally twice daily for patients with frequent recurrences (≥6 episodes per year) 4
• Suppressive therapy reduces recurrence frequency by ≥75% and reduces asymptomatic viral shedding 4
• Among immunocompetent adults, 55% remained recurrence-free at 6 months and 34% at 12 months with valacyclovir 1 gram once daily 5
• In HIV-infected adults, 65% remained recurrence-free at 6 months with valacyclovir 500 mg twice daily versus 26% with placebo 5

Special Clinical Scenarios

Pregnancy Considerations

HPV:

• Vaccination does not protect against persistent infection or lesions from HPV types already present at time of vaccination 1
• Routine screening continues per standard guidelines 1

Genital Herpes:

• Suppressive-dose acyclovir (400 mg TID) starting at week 36 prevents HSV recurrences requiring cesarean delivery 3
• Elective cesarean delivery should be offered to patients with active lesions to reduce neonatal HSV exposure 2
• Acyclovir remains pregnancy category B despite one case-control study showing increased gastroschisis risk (4.7-fold), which had significant demographic differences and possible recall bias 3

Immunocompromised Patients

HPV:

• HIV-infected individuals should receive 3-dose HPV vaccination series at ages 11-12 years or catch-up through age 26 if not previously vaccinated 1
• HIV-infected MSM are at increased risk for anal dysplasia and cancer 1

Genital Herpes:

• Suppressive therapy is effective in preventing reactivation in immunocompromised hosts 6
• Acyclovir-resistant infections may occur, particularly in profoundly immunosuppressed individuals 3, 7
• Case reports suggest brincidofovir, imiquimod, and topical cidofovir may be useful for acyclovir-resistant HSV 3, 4

Critical Distinctions in Natural History

HPV

• Most HPV infections are cleared by the immune system without clinical complications 8
• Clinical sequelae of low-risk HPV include genital warts 8
• High-risk HPV manifestations include abnormal Pap tests, LSIL, HSIL, and cervical cancer 8

Genital Herpes

• HSV is an incurable, lifelong infection with periodic reactivation and variable viral shedding 2
• Genital HSV-1 has less shedding and fewer recurrences compared to HSV-2, particularly after the first year 3
• Approximately 60% of individuals exposed to HSV-2 do not develop symptoms, yet can still transmit the virus 7
• Only 13% of HSV-2 seropositive persons have been diagnosed with genital herpes 3

Common Pitfalls

HPV:

• Neither routine surveillance for HPV infection nor partner notification is useful for prevention, as the majority of partners are already infected 1
• HPV vaccination does not eliminate need for continued cervical cancer screening 1

Genital Herpes:

• Genital herpes is frequently transmitted during asymptomatic viral shedding, not just during visible outbreaks 5, 2
• Suppressive therapy for genital HSV-1 has not been shown to reduce transmission to sexual partners 3
• Suppressive therapy is not effective to decrease transmission risk among persons with HIV/HSV-2 coinfection 3
• Valacyclovir has not been shown to reduce transmission of sexually transmitted infections other than HSV-2 5