Herpes simplex virus type 2 (HSV-2)

Test code: S0030 - Qualitative detection of Herpes Simplex Virus Type 2 (HSV-2) by polymerase chain reaction

Herpesviruses have been isolated from a wide variety of mammalian and non-mammalian species. The eight human herpesviruses, herpes simplex virus type 1 and 2 (HSV-1 and -2), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), human cytomegalovirus (CMV), and human herpesviruses-6, -7 and -8 (HHV-6, -7 and -8), represent a significant public health problem worldwide. These viruses have been further classified as members of the alpha-herpesvirus (HSV-1, HSV-2 and VZV), the beta-herpesvirus (CMV, HHV-6 and HHV-7) and the gamma-herpesvirus subgroups (EBV and HHV-8). The virus-host relationship is characterized by the benign nature of HSV infection in its usual host, man, and by the fatal disease it causes in accidental hosts, such as the owl monkey or gibbon. Fatal infections caused by HSV have been documented in gibbons, patas and colobus monkeys. A natural epizootic model of Herpesvirus hominis is splenectomized gibbons, which clinically mimic the disease as it occurs in man.

A recent serological study to screen for these herpesviruses in gibbons using antibodies for herpes simplex virus type 1 (HSV-1), herpes simplex virus type 2 (HSV-2), Epstein-Barr virus (EBV) and cytomegalovirus (CMV) had shown that the prevalence of IgG antibodies against HSV-1, HSV-2, EBV and CMV was 28.2%, 28.2%, 14.1% and 17.9%, respectively. Although cross-reactivities with other monkey herpesviruses cannot be ruled out, the possibility of direct transmission of these human herpesviruses exists. For example, hand rearing of gibbon infants by zoo personnel would provide ample opportunity for human herpesvirus transmission to gibbons. Moreover, the exclusive HSV serotypes within species suggests that these viral infections may have originated from a common source within a species, with subsequent spread from animal to animal, rather than from isolated human-to-gibbon transmissions. Accordingly, HSV-2 infections have been observed to spread from chimpanzee to chimpanzee.

Although virus isolation can be used to diagnose HSV-2 virus infection and determine carrier status, it is not very sensitive or specific, and viral culture increases the potential risk of laboratorians contacting this virus. Serological testing for HSV-2 is difficult because of the close antigenic relation among different herpesviruses.

HSV-2 detection by PCR is the most rapid, sensitive and specific method for diagnosis of this infection and confirmation of carrier status.

Utilities:

• Confirm the disease causing agent
• Ensure that animal colonies are free of HSV-2
• Early prevention of spread of this virus among a colony
• Minimize personnel exposure to this virus
• Safety monitoring of biological products and vaccines that derive from primates

Specimen requirement: Lesion swab, conjunctival swab or 1 ml whole blood in EDTA (purple top) or ACD (yellow top) tube, shipped overnight at room temperature.

For specimen types other than those listed here, please call to confirm specimen acceptability and shipping instructions.

For all specimen types, if there will be a delay in shipping, or during very warm weather, refrigerate specimens until shipped and ship with a cold pack unless more stringent shipping requirements are specified. Frozen specimens should be shipped so as to remain frozen in transit. See shipping instructions for more information.

Turnaround time: 2 business days

Methodologies: Qualitative PCR

Normal range: Nondetected