Rapid diagnosis of herpes simplex virus 1 and 2 bloodstream infections utilizing a sample-to-answer platform.

Bloodstream HSV-1 and HSV-2 infections can cause devastating outcomes with high morbidity and mortality, especially in neonates or immunocompromised individuals. Proper patient management for herpes simplex virus (HSV) bloodstream infections is time-sensitive and requires a rapid, accurate, and definitive diagnosis. The absence of the U.S. Food and Drug Administration (FDA)-approved molecular assays for HSV detection in blood, coupled with a lack of consensus on the optimal sample type, underscores the unmet need for improved diagnostics. We prospectively compared the cycle threshold values in paired samples including whole blood (WB), plasma, serum, and peripheral blood mononuclear cells (PBMCs) from patients with bloodstream HSV infections. This analysis employed a modified use of the FDA-cleared Simplexa HSV-1 & 2 Direct assay. The clinical performance in serum was assessed by comparing the results of 247 remnant specimens on this sample-to-answer platform to established laboratory-developed tests in a blinded fashion. Serum samples exhibited significantly lower cycle thresholds than whole blood samples [2.6 cycle threshold (Ct) bias, IMPORTANCE: Rapid, accurate, and definitive diagnosis of herpes simplex virus (HSV) infections is crucial in clinical settings for patient management. The absence of FDA-authorized molecular assays for HSV-1/2 detection in blood, coupled with a lack of consensus on the optimal sample type, underscores the need for improved diagnostic methods. Furthermore, rapid diagnosis of HSV bloodstream infections enables timely administration of antiviral treatment, influences patient management decisions for those at high risk, and can contribute to shorter hospital stays, thereby reducing healthcare costs.