INTENDED USE

The HSV-2 IgG/IgM Test is a lateral flow chromato-graphic immunoassay for the qualitative detection and differentiation of anti-herpes simplex virus-2 (HSV-2) IgG and IgM in human serum, plasma or whole blood. The test is intended to be used by professionals as a screening test and as an aid in the diagnosis of infection with HSV-2. Any reactive result with the HSV-2 IgG/IgM Test must be confirmed with alternative testing method(s) and clinical findings.

SUMMARY

Herpes simplex viruses of the family Herpesviridae include two types of DNA viruses, herpes simplex virus-1 (HSV-1) and herpes simplex virus-2 (HSV-2). HSV-2 is nearly always sexually transmitted and is the main cause of genital herpes. HSV-1 and HSV-2 can infect both genital and orofacial areas. Up to 50% of first-episode cases of genital herpes are caused by HSV-1, but recurrences are much less frequent for genital HSV-1 infection than genital HSV-2 infection. Subclinical viral shedding is less frequent for genital HSV-1 than for genital HSV-2. Genital HSV infection has also been associated with increased risk of sexual transmission of HIV. After primary infection, these viruses persist in a latent state for life.
One of the biggest risks associated with HSV is neonatal transmission. The majority of neonatal transmissions occur in pregnant women with primary HSV infections. 85% to 90% of neonatal transmissions occur at the time of delivery with only 5% of infections occurring intrauterine. Clinical manifestations of neonatal infection with HSV range from local lesions of the skin, mouth, eye or central nervous system to severe, widespread dissemination involving visceral organs and potentially death.
Serology is an effective means of diagnosing HSV because the manifestation of symptoms is transient and the infection is often undiagnosed. Anti-HSV IgM can be detected 9-10 days after exposure and last for 7-14 days, though they may remain detectable for up to 6 weeks. Anti-HSV IgM is often associated with primary infection but may be detectable during recurrence of the disease. Anti-HSV IgG can be detected 21-28 days post exposure and detectable titers typically remain for life. Detection of anti-HSV IgM in the absence of anti-HSV IgG can be an effective method of detecting early stages of HSV infection and as an indicator of potential primary infection.
The HSV-2 IgG/IgM Test uses HSV-2 glycoprotein G2 for the specific detection and differentiation of IgG and IgM antibodies to HSV-2 in serum, plasma and whole blood. The test can be performed by minimally-skilled personnel without the use of laboratory equipment. The result is available after 10 Minutes.

PRINCIPLES

The HSV-2 IgG/IgM Test is a lateral flow chromatographic immunoassay. The test cassette consists of: 1) a burgundy conjugate pad containing HSV-2 antigens conjugated with colloidal gold (HSV-2 conjugates) and control antibodies conjugated with colloidal gold, 2) a nitrocellulose membrane strip containing two test lines (M and G) and a control line (C).
Mouse anti-human IgM antibodies for the detection of anti-HSV-2 IgM are pre-coated on the line ‘M’, mouse anti-human IgG antibodies for the detection of anti-HSV-2 IgG are precoated on the line ‘G’ and control antibodies are pre-coated on the control line (C). When an adequate volume of specimen and buffer is dispensed into the sample well (S), the specimen migrates by capillary action along the test cassette. If anti-HSV-2 IgM are present in the specimen, they bind to the HSV-2 conjugates. The immunocomplexes are then captured on the membrane by the pre-coated mouse anti-human IgM antibodies, forming a burgundy line ‘M’, indicating an HSV-2 IgM positive test result. If anti-HSV-2 IgG are present in the specimen, they also bind to the HSV-2 conjugates. The immunocomplexes are then captured on the membrane by the pre-coated mouse anti-human IgG antibodies, forming a burgundy line ‘G’, indicating an HSV-2 IgG positive test result. The absence of both test lines (M and G) suggests a negative result.
The test contains an internal control (C) which should always exhibit a burgundy line of the immunocomplex of control line antibodies, regardless of the colour development of the test lines (M and G). Otherwise, the test result is invalid and the specimen should be retested with another test cassette.