A simple biological marker to differentiate the types of Herpes Simplex Viruses in resource-limited settings

A Nessa,M Jahan,S Tabassum,T Akter

doi:10.3329/bmrcb.v38i1.10448

Abstract

Herpes simplex viruses (HSV) multiply readily on the chorioallantoic membrane (CAM) of embryonated hen's egg and produce easily visible foci or pocks on this membrane. In the present study, pocks produced by the two antigenic types of HSV (1 & 2) were compared to evaluate the effectiveness of typing HSV isolates by pock size on CAMs. A total of 57 HSV isolates from both non-genital and genital samples were typed by the pock size produced on the CAMs of fertile hen's eggs. Twenty two HSV isolates yielded visible pocks on CAM, of which 9 (40.9%) produced small pocks, while 13 (59.1%) produced large pocks. All pocks produced on CAM were confirmed by antigenic typing by the Direct Fluorescent Antibody (DFA) method. HSV isolates which produced small pocks were in complete (100%) concordance with HSV type-1, while those producing larger pocks were in full (100%) concordance with HSV type-2. Thus, the pock size on CAM of embryonated fertile hen's egg may be used as a simple and relatively inexpensive biological marker for the differentiation of HSV types 1 & 2.

Highlights

Herpes simplex virus (HSV) can be differentiated antigenically into two groups, types 1 & 2
The present study sought to demonstrate the relationship of pock size with the two antigenic types of HSV isolated from clinical samples of both genital and non-genital sites
Our study observed that almost all (92.9%) HSV isolates from genital lesions produced large pocks on the chorioallantoic membrane (CAM), which were confirmed by the more reliable Direct Fluorescent Antibody (DFA) method as HSV-2

Summary

Introduction

Herpes simplex virus (HSV) can be differentiated antigenically into two groups, types 1 & 2. Type-1 is generally associated with non-genital infections while type-2 is commonly associated with genital infections, both types may cause similar diseases at both anatomical sites[1]. The frequency of reactivation of HSV is influenced by anatomic site and the type of virus[2]. Genital HSV-2 infection is twice as likely to reactivate and recurs 8-10 times more frequently than genital HSV-1 infection. Oral-labial HSV-1 infection recurs more frequently than oral-labial HSV-2 infection[3]. It is important to identify the type of HSV which cause herpetic (herpes labialis or genital herpes) infections as this influences prognosis and treatment recommendations[4]. Typing of HSV influences counseling of patients[5]

Methods

Results

Conclusion