Several recent studies found that false-positive HSV results are not unlikely in select patient groups tested by ELISAs. Positive predictive value (PPV) refers to the proportion of patients with positive test results who actually have the disease (i.e., true positives), and in low-prevalence settings, even tests with high sensitivity and specificity can have poor positive predictive values. 17 - 19 However, the prevalence of a disease in a population affects screening test performance. 15 HerpeSelect HSV-1 and HerpeSelect HSV-2 enzyme-linked immunosorbent assays (ELISA) (Focus Diagnostics, Cypress, CA) are among the most commonly used tests for serodiagnosis of HSV infection 16 and have previously been shown to be sensitive and specific for the diagnosis of HSV-2 in high-prevalence populations. In the Prevention Agenda for Genital Herpes, the Centers for Disease Control and Prevention called for studies that describe the “real world” performance of type-specific assays for herpes virus infections. In addition, experts have recently suggested that an awareness of HSV-1 antibody status can assist in the interpretation of a serological diagnosis of HSV-2. However, interest in HSV-1 testing has increased concomitantly with the awareness of HSV-1 as a cause of genital herpes and the affect of HSV type on the prognosis and subsequent counseling related to an infection. 11 - 13 Because of the low associated morbidity and lack of associated social stigma, until recently serological testing for HSV-1 had not been considered valuable by most experts and had not been requested by patients. 8 - 10 Others express concerns about the accuracy of the tests, the burden on healthcare practitioners to provide counseling, and the psychosocial distress that may accompany a diagnosis. Some experts argue that identifying people with unrecognized HSV-2 may result in a decreased risk of transmission from such persons to others. In the last decade, type-specific serological assays that detect HSV-1 and HSV-2 antibodies have become commercially available, prompting debate about their use as a screening test. 3 While HSV-1 is primarily the cause oral-labial herpes and HSV-2 causes genital infection, HSV-1 accounts for increasing proportions of newly diagnosed primary genital herpes. 1 Over two-thirds are unaware of their infections, and the majority of infections are transmitted by these individuals. 2 In the reported literature, approximately 17% of adults in the United States have antibodies to HSV-2 and 58% have antibodies to HSV-1. 1 They are associated with substantial morbidity and transmission and acquisition of the human immunodeficiency virus (HIV). INFECTIONS CAUSED BY THE HERPES simplex virus types 1 (HSV-1) and 2 (HSV-2) are highly prevalent.
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