Viral Shedding 1 Year Following First-Episode Genital HSV-1 Infection

Area of Science:

• Virology
• Immunology
• Epidemiology

Background:

• Herpes simplex virus type 1 (HSV-1) is a primary cause of genital herpes globally.
• Understanding HSV-1 shedding and immune responses is crucial for managing transmission and counseling.

Purpose of the Study:

• To assess oral and genital HSV-1 shedding patterns in individuals with first-episode genital HSV-1 infection.
• To characterize the development of HSV-specific antibody and T-cell responses.
• To inform public health counseling regarding genital HSV-1 transmission.

Main Methods:

• A prospective cohort study followed 82 participants for up to 2 years.
• Participants provided self-collected oral and genital swabs for HSV-1 polymerase chain reaction (PCR) testing.
• Blood samples were collected serially to assess HSV-specific antibody and T-cell responses (interferon-γ enzyme-linked immunospot).

Main Results:

• Genital HSV-1 shedding was detected in 64.6% of participants at 2 months, declining to 7.1% at 11 months.
• Primary HSV-1 infection was associated with a higher risk of genital shedding (RR, 2.75).
• Oral shedding occurred in 29.3% at 2 months, and genital lesions were rare.

Conclusions:

• Genital HSV-1 shedding is frequent following a first episode, particularly in primary infections.
• Shedding rates decline substantially within the first year post-infection.
• Maintained polyfunctional T-cell responses suggest robust immune control over time.