Vaccines and Herpes Simplex Virus Type 1 (HSV-1)
Direct Answer
Standard vaccines are safe for individuals with HSV-1 infection, and there is no contraindication to routine immunization in HSV-1 positive persons. HSV-1 infection does not compromise the immune system in a way that would preclude vaccination with either inactivated or live-attenuated vaccines in otherwise immunocompetent individuals 1.
Routine Vaccination Safety in HSV-1 Positive Individuals
Inactivated Vaccines
- All standard inactivated vaccines (influenza, pneumococcal, hepatitis B, HPV, etc.) can be safely administered to individuals with HSV-1 without any special precautions or timing considerations 1.
- There is no evidence that routine vaccination triggers HSV-1 reactivation or worsens disease outcomes 1.
Live-Attenuated Vaccines
- Live-attenuated vaccines (MMR, varicella, zoster) are safe in immunocompetent individuals with HSV-1 infection 1.
- The presence of HSV-1 infection alone does not constitute immunocompromise and is not a contraindication to live vaccines 1.
Special Considerations for Herpes Zoster Vaccination
Shingrix (Recombinant Zoster Vaccine)
- Shingrix is the preferred herpes zoster vaccine for adults ≥50 years, administered as a 2-dose series with the second dose given 2-6 months after the first dose 2.
- This non-live recombinant vaccine demonstrates 97.2% efficacy in preventing shingles and is safe for all individuals, including those with HSV-1 2.
- HSV-1 infection does not affect the safety profile or efficacy of Shingrix 2.
Live-Attenuated Zoster Vaccine (Zostavax)
- While Zostavax can be administered to immunocompetent HSV-1 positive individuals, it is no longer the preferred option due to inferior efficacy compared to Shingrix 2.
- Zostavax efficacy declines to only 14.1% by year 10, whereas Shingrix maintains efficacy above 83.3% for at least 8 years 2.
HIV-Coinfected Individuals with HSV-1
Vaccination Approach
- HIV-infected persons with HSV-1 should receive all age-appropriate inactivated vaccines according to standard schedules 1.
- Live-attenuated vaccines should be avoided in HIV-infected individuals with significant immunosuppression (CD4+ count considerations apply) 1.
- Antiviral prophylaxis after exposure to HSV or to prevent initial episodes among persons with latent HSV infection is not recommended 1.
Immunocompromised Patients with HSV-1
General Principles
- Inactivated vaccines are generally acceptable for immunocompromised individuals with HSV-1 1.
- Live-attenuated vaccines should be avoided in patients receiving immunosuppressive therapy (high-dose corticosteroids >20 mg/day prednisone equivalent, biologics, chemotherapy) 1.
- For immunocompromised adults ≥18 years with HSV-1, Shingrix can be safely administered with a shortened schedule (second dose at 1-2 months) 2.
HPV Vaccination in HSV-1 Positive Individuals
Specific Recommendations
- HPV vaccination should be administered according to standard ACIP guidelines (ages 11-26 years) regardless of HSV-1 status 1.
- There is no interaction between HSV-1 infection and HPV vaccine safety or efficacy 1.
- The presence of one sexually transmitted infection (HSV-1) does not contraindicate vaccination against another (HPV) 1.
Investigational HSV-1 Vaccines
Current Development Status
- Multiple HSV-1 vaccine candidates are in preclinical and early clinical development, including live-attenuated strains, subunit vaccines, and DNA vaccines 3, 4, 5.
- No FDA-approved prophylactic or therapeutic HSV-1 vaccine currently exists 3, 5.
- Live-attenuated HSV-1 vaccine candidates (such as VC-2 and NS-gEnull strains) have shown promise in animal models with cross-protection against HSV-2, but remain investigational 6, 7.
Common Pitfalls to Avoid
- Do not confuse HSV-1 infection with immunocompromise—HSV-1 alone does not warrant special vaccination precautions in otherwise healthy individuals 1.
- Do not delay routine vaccinations in HSV-1 positive patients—there is no need to wait for periods of viral quiescence or adjust timing around outbreaks 1.
- Do not use live-attenuated vaccines in patients on immunosuppressive therapy, even if their only infection is HSV-1 1.
- Do not confuse varicella-zoster virus (VZV) vaccines with HSV vaccines—these are distinct viruses, and zoster vaccination does not affect HSV-1 2.