Comparison of Western blot (immunoblot) and glycoprotein G-specific immunodot enzyme assay for detecting antibodies to herpes simplex virus types 1 and 2 in human sera

TLDR

Sera from patients with culture‑proven genital herpes were tested for HSV‑1 and HSV‑2 antibodies using both a Western blot (WBA) and glycoprotein G–specific immunodot enzyme assays (IEAs). All 137 samples were correctly typed by both WBA and IEA; after ≥21 days post‑onset, sensitivity was 99 % (WBA) and 96 % (IEA) for HSV‑2, while WBA detected 94 % of primary HSV‑1 cases versus 53 % by IEA, though both assays may miss early HSV‑2 seroconversion.

Abstract

Sera from patients with culture-proven genital herpes infections were tested for herpes simplex virus type 1 (HSV-1)- and HSV-2-specific antibodies by both a Western blot (immunoblot) technique (WBA) and immunodot enzyme assays (IEAs) specific for HSV-1 or HSV-2 glycoprotein G (gG). Of 137 serum samples tested, none was mistyped by either WBA or IEA. Both tests were most sensitive with sera obtained at least 21 days after onset of primary HSV-2 infections or sera drawn during recurrent HSV-2 genital episodes: 75 of 76 (99%) such serum samples were positive for HSV-2 antibody by WBA and 73 of 76 (96%) were positive by IEA. Of sera drawn earlier than 21 days from onset of primary genital HSV-2, antibodies to HSV-2 were detected in 25% by WBA and 8% by IEA. In patients with culture-proven primary genital HSV-1 infection, WBA detected antibodies to HSV-1 proteins in 16 of 17 (94%) serum samples drawn at least 21 days after onset of primary genital HSV-1 infection, compared with 9 of 17 (53%) serum samples tested for gG-1 by IEA. Both WBA and IEA are accurate and sensitive tests for HSV-2 antibody in patients convalescing from a first episode or having symptomatic or asymptomatic recurrent genital herpes. WBA was more sensitive than IEA in detecting seroconversion following primary HSV-1 genital herpes, although both assays may miss persons undergoing early seroconversion to HSV-2.