HSV-1 infection does not demonstrate life-long IgG seropositivity in 100% of exposed people. After primary infection, HSV-1 establishes a latent infection in the neurons of the peripheral nervous system in the sensory ganglia. Stimuli including nerve trauma, UV light, stress, fevers, menstruation, among other stimuli, can induce reactivation of HSV-1, and the reactivation may be symptomatic or asymptomatic.
While it is understood that HSV-1 IgG positivity may remain high after primary reinfection in approximately 90% of cases, and that viral reactivation typically leads to stronger IgG avidity, the understanding of immunologic control of HSV-1 and the timeline for IgM and IgG positivity remains incomplete, particularly in people who may not be immunocompetent.
Consider testing Total Immunoglobulins (Total IgA, Total IgG, Total IgE, Total IgM) to assess for hypogammaglobulinemia which may have impacted immune response and serological results.
Additionally, there is higher sensitivity and specificity for detecting HSV-1 in vesicular fluid as compared to serum. While Vibrant does not offer HSV-1 culture of vesicular fluid, HSV-1 culture of vesicular fluid may be considered as indicated for further workup of chronic oral mucocutaneous lesions.
