Background Information

Herpes simplex virus 1/2 (HSV)


Herpes Simplex virus (HSV) is a highly adapted human pathogen with a rapid replication cycle with the ability to invade sensory neurons where the virus is lifelong latent. Such latent infections can reactivate in peripheral tissues adjacent to the latent infected neurons. Reactivation may be triggered by signals such as sunlight, stress cold or immune suppression which leads to transcriptional activity in the harboring neuron. HSV falls into four categories, types 1, 2, 6 and 8. In humans, type 1 infects the mouth and type 2 infects the genital tract, but there is a substantial overlap. Type 6 causes an infection in infancy and type 8 is associated with Kaposi's sarcoma which is seen in HIV.

Infections with herpes HSV are very common in humans and it is estimated that 90% of all humans experience oral herpes infections before the age of 10. HSV-1 causes an acute infection of gums, lips and sides of the mouth. HSV-2 causes infections in the genital region and affects 20-25% of the population and causes sores and blisters in the genital region. HSV is contagious and is transmitted by close contact (sexually transmitted) through active herpes blisters. HSV-1 establishes latency in the trigeminal ganglion whereas HSV-2 resides in the sacral ganglion. However, this difference is not absolute; either type can reside in either or both sites. HSV infections are usually mild. In some cases though, severe clinical manifestation of HSV infection may cause encephalitis, corneal blindness and it can lead to a spectrum of vesicular and necrotizing inflammatory conditions, mainly of the skin and mucous membranes, and disseminate in patients with secondary immunodeficiency syndromes. Both type 1 and 2 can cause intrauterine, neonatal and postnatal infections in newborns which has poor prognosis.

PanPath's REMBRANDT® kit for HSV is designed for the detection of both types 1 and 2 since it is not necessary to distinguish between type 1 and 2 for diagnostic purposes. The kit therefore contains total genome DNA (153 Kb) probes for HSV type 1 and HSV type 2. No cross-hybridization occurs with target DNA of other viruses provided that the hybridization conditions as laid out in the protocol are strictly followed.