Cold sores

The herpes simplex virus (HSV) (also known as Cold Sore, Night Fever, or Fever Blister) 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. During this time, the asymptomatic person should be extremely careful (washing hands frequently; not touch the blister area, etc.) since transmission is still possible. An infection on the lips is commonly known as a "cold sore" or "fever blister". These are sometimes confused with canker sores or Apthous ulcers which have a similar appearance; these appear inside the mouth and are not caused by the herpes simplex virus.

Herpes simplex is an infection that primarily affects the mouth or genital area.

Causes, incidence, and risk factors

There are two different strains of herpes simplex viruses:

Herpes simplex virus type 1 (HSV-1) is usually associated with infections of the lips, mouth, and face. It is the most common herpes simplex virus and is usually acquired in childhood. HSV-1 often causes lesions inside the mouth such as cold sores (fever blisters) and is transmitted by contact with infected saliva. By adulthood, up to 90% of individuals will have antibodies to HSV-1.

Herpes simplex virus 2 (HSV-2) is sexually transmitted. Symptoms include genital ulcers or sores. In addition to oral and genital lesions, the virus can also lead to complications such as meningoencephalitis (infection of the lining of the brain and the brain itself) or cause infection of the eye -- in particular the conjunctiva, and cornea. However, some people have HSV-2 but do not display symptoms. Up to 30% of U.S. adults have antibodies against HSV-2. Cross-infection of type 1 and 2 viruses may occur from oral-genital contact. A finger infection, called herpetic whitlow, is another form of herpes infection. It usually affects health care providers who are exposured to oral secretions during procedures. Sometimes, young children contract the disease.

A herpes virus can infect the fetus and cause congenital abnormalities. It may also be transmitted to a newborn during vaginal delivery in mothers infected with herpes viruses, particularly if the mother has active infection at the time.

However, the virus may be transmitted even in the absence of symptoms or visible lesions.

Symptoms

mouth sores genital lesions (male) -- may be preceded by burning or tingling sensation genital lesions (female) -- may be preceded by burning or tingling sensation blisters or ulcers -- most frequent on the mouth, lips and gums or genitalia fever blisters fever -- may be present especially during the first episode enlargement of lymph nodes in the neck or groin

Signs and tests

In many instances, the physical appearance of the lesions is highly suggestive of the diagnosis of herpes-simplex infections. However, certain tests may be ordered to establish a definitive diagnosis. They include:

Blood test
 * Viral culture of lesion
 * Tzanck test
 * Direct fluorescent antibody (DFA) test

Treatment

Some cases are relatively mild and may not require treatment.

In severe or prolonged cases, or in individuals who are immunosuppressed or who have frequent recurrences, antiviral medications such as acyclovir may be used.

In individuals with more than 6 recurrences of genital herpes per year, chronic antiviral medications may be offered to reduce recurrences.

Support Groups

Support groups and dating services are available for people with genital herpes.

Expectations (prognosis)

The oral or genital lesions usually heal on their own in 7 to 10 days unless an individual has an underlying condition that weakens the immune system, in which case the infection may be more severe and last longer.

Once infected, the virus spreads to nerve cells and stays in the body for the rest of a person's life. It may intermittently reactivate and cause symptoms, or flares. Recurrences may be precipitated by overexposure to sunlight, fever, stress, acute illness, and medications or conditions that weaken the immune system (such as cancer, HIV/AIDS, or use of corticosteroids).

Complications
 * meningitis
 * encephalitis
 * eczema herpetiform (widespread herpes across the skin)
 * infection of the eye -- keratoconjunctivitis
 * prolonged, severe infection in immunosuppressed individuals
 * pneumonia
 * infection of the trachea
 * Calling your health care provider

Call your health care provider if you develop symptoms which appear to be herpes infection. There are many different conditions that can cause similar lesions (particularly in the genital area).

If you have a history of herpes infection and develop similar lesions, notify your health care provider if they do not resolve after 7 to 10 days, or if you have a condition that weakens your immune system.

Prevention

Prevention is difficult since the virus can be spread to others when an infected person has no evidence of an active outbreak.

Avoiding direct contact with an open lesion will lower the risk of infection.

People with genital herpes should avoid sexual contact when active lesions are present. Safer sex behaviors, including the use of condom, may also lower the risk of infection.

Individuals with active herpetic lesions should also avoid contact with newborns, children with eczema, or immunosuppressed individuals as these groups are at higher risk for more severe disease.

To decrease the risk of infecting the newborn, a cesarean delivery (C-section ) is recommended for pregnant women who have active herpes simplex infection at the time of delivery.