(P171) Does Genital Herpes Symptom History Predict Herpes Simplex Virus Type 2 Antibody Positivity?

Background: Herpes simplex infections are common and cause substantial morbidity and mortality. There is no national strategy to control herpes simplex infections. The positive predictive value of current HSV-2 antibody tests is a concern. The US Centers for Disease Control and Prevention recommends serologic screening for HSV-2 in individuals with a history of genital herpes symptoms. However, no validated symptom screening tool currently exists. We developed and evaluated a genital herpes symptom screening tool to predict HSV-2 antibody positivity among STI clinic patients in Lima, Peru.

Methods: We recruited and enrolled participants visiting public STI clinics who agreed to complete a tablet-based survey of prior genital herpes symptoms (anogenital ulcers, genital, or inguinal pain, burning, itchiness or tingling or constitutional symptoms with one or more other symptoms). For this analysis, individuals reporting current genital herpes symptoms were excluded to focus on asymptomatic screening. Survey findings were compared with semi-quantitative HSV-2 serological test results (Anti-HSV-2 (gG2) ELISA IgG (Euroimmun, Germany)). Sera with optical density index values < 0.80 were considered anti-HSV-2 negative, between 0.80 and 2.9 were considered anti-HSV-2 equivocal, and ≥3.0 were considered anti-HSV-2 positive.

Results: We enrolled 131 participants between July-October 2022. We found that 21.2% of patients were anti-HSV-2 positive, 39.4% were anti-HSV-2 equivocal, and 39.4% were anti-HSV-2 negative. Anti-HSV-2 positivity among asymptomatic participants reporting no prior genital herpes symptoms was 18% while 26% in those with at least one prior symptom. Positivity increased to 33% in those with 4 or more symptoms. There was a 1.47-fold (95% CI 0.77 - 2.83) increase in anti-HSV-2 positivity in those with any prior genital herpes symptoms compared to those with none.

Conclusion: Testing only those with a history of any prior genital symptoms might increase the likelihood of identifying HSV-2 infected individuals and improve the positive predictive values of current HSV-2 antibody tests. However, the 18% with no prior genital herpes symptoms would be missed using this testing strategy. The high number of equivocal tests is an additional issue that requires attention, resolution of equivocal values with Western blot testing is underway.