Herpes Simplex Virus (hsv) Infection of the Mouth

Definition Herpes viruses are a large family of parasites able to infect humans. All are DNA viruses capable of latency. Among human herperviruses there are two variants Herpes Simplex Virus type-1 (HSV-1) and type–2 (HSV-2), which can be – as well as other clinical signs and symptoms – responsible for oro-facial disease. Usually HSV-1 infections affect the face and mouth while HSV-2 infections occur genitally. Both viruses may cause recurrent disease. HSV usually enters humans via the mouth. Oro-genital and penetrative intercourse, contact sports, some high risk occupations and corneal transplant surgery have been associated with HSV transmission. The first episode of HSV infection in humans who have not previously been exposed to HSV-1 and HSV-2 is called the primary infection. Symptoms are not always present during the first infection, and therefore patients may be unaware that they have been exposed to the virus. Following primary infection the virus travels through the nerves that give sensation to the area infected. Once it enters the root of these nerves – the ganglion – it remains there for life. When the virus reactivates, it can cause mucosal or skin lesions in roughly the same area to that where it originally entered the body: these manifestations are defined as recurrences.