Herpes simplex virus
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- This article is about the virus. For information about the disease, see Herpes simplex. For information on the United States Navy Ship, see HSV-2 Swift.
The herpes simplex virus (HSV) is a virus that manifests itself in two common viral infections, each marked by painful, watery blisters in the skin or mucous membranes (such as the mouth or lips) or on the genitals. The disease is contagious, particularly during an outbreak, and is incurable with present technology. An infection on the lips is commonly known as a "cold sore" or "fever blister". These are sometimes confused with canker sores or aphthous ulcers, which have a similar appearance; these appear inside the mouth and are not caused by the herpes simplex virus. When asymptomatic, HSV lies dormant in the bodies of the nerve cells, replicating within the axons towards the skin during an outbreak. When the outbreak has passed, the virus 'dies back' along the nerve until it is only present in the nerve body.<ref>Herpes simplex. DermNet NZ - New Zealand Dermatological Society (16 Sep 2006). Retrieved on 2006-10-15.</ref> The dormancy of the virus within the nerve bodies contributes to the difficulty of treatment.
[edit] Transmission
HSV is generally transmitted by direct contact of lips and/or genitals when the sores are present, or just before they appear (known as shedding). In addition, herpes may be transmitted during childbirth, which can be fatal to the infant. The immature immune system of the child is unable to defend against the virus and even if treated, infection can result in brain damage. Transmission occurs while passing through the birth canal and the risk of infection is minimal if there are no symptoms or exposed blisters during delivery. The first outbreak after exposure to HSV is commonly more severe than future outbreaks, as the body has not had a chance to produce antibodies; this first outbreak also carries the risk of developing meningitis.
Outbreaks are generally preceded by sensations of burning, itching or tingling before visible blistering occurs. Subclinical shedding can also occur at any time, resulting in transmission without symptoms.
[edit] Treatment
There is currently no cure or vaccine for HSV. Treatment is available in the form of antiviral medications such as Aciclovir (trade name Zovirax), which reduces the duration of symptoms and accelerates healing. Treatment should begin at the first symptoms of an outbreak for best results as far as duration and healing; should treatment begin before the lesions appear, it is possible that the outbreak can be averted.
Another option is the use of daily suppressive therapy, in which antivirals are taken every day over the course of years. Suppressive therapy reduces frequency of symptoms and recurrence of outbreaks. In addition, suppressive therapy reduces subclinical shedding, lowering the risk of transmission through sexual contact or kissing.
The amino acid lysine has demonstrated the ability to reduce the duration of infection through inhibiting the replication of the HSV. When foods high in lysine are consumed in preference to foods high in arginine, HSV replication may be inhibited; conversely, consuming foods high in arginine may interfere with the therapeutic use of lysine.
[edit] Legal redress
Whether the law can help a person who catches HSV depends on the jurisdiction where it was contracted as legal jurisdictions define their own rules regarding the transmission of STIs such as HSV.<ref>link Webpage on social aspects of genital herpes</ref> In England, the case of R. v. Sullivan a man was prosecuted for sexual assault after his partner experienced a primary outbreak of genital herpes, on the basis that he had failed to the fact that he had herpes. Ultimately the man was not prosecuted due to an inability to prove prior knowledge. Within the United States, civil claims for transmission of herpes are heard in all 50 jurisdictions, usually based on negligence if transmission was accidental and battery if deliberate. The first successful case to allow such a claim was Kathleen K. v. Robert B., decided by the California Court of Appeals.
