Herpes simplex

Definition

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.

References

Stoopler ET. Oral herpetic infections (HSV 1-8). Dent Clin North Am. 2005 Jan;49(1):15-29, vii.

Mandell GL, Bennett JE, Dolin R. Principles and Practice of Infectious Diseases.  5th ed. Philadelphia, Pa: Churchill Livingstone; 2000.

Illustrations

Herpetic whitlow on the thumb

Herpes simplex - close-up

Page Content:

herpes simplex; herpes simplex virus; 1 herpes simplex; 2 herpes simplex; 1 herpes simplex virus; 1 herpes simplex type; encephalitis herpes simplex; 1 herpes simplex type virus; herpes picture simplex; herpes picture simplex virus; 1 herpes picture simplex; 2 herpes picture simplex; 2 herpes simplex virus; herpes simplex symptom; 2 herpes simplex type; herpes i simplex; herpes ii simplex; herpes keratitis simplex; herpes simplex treatment; 2 herpes simplex type virus; herpes one simplex; eye herpes simplex; disease herpes simplex skin; 1 2 herpes simplex; genital herpes simplex; herpes infection simplex; herpes oral simplex; herpes ii simplex type; 1 1 herpes hsv simplex virus; cure herpes simplex; herpes link simplex suggest; cold herpes simplex sore; herpes simplex symptom virus; b herpes simplex; herpes information simplex; herpes photo simplex; 1 herpes simplex symptom; herpes simplex type; herpes ocular simplex; herpes ii simplex virus; herpes simplex treatment virus; herpes i simplex virus; herpes simplex two; 3 herpes simplex; herpes infection simplex virus; 1 genital herpes simplex; herpes simplex transmission; cause herpes simplex; acyclovir herpes simplex; herpes medication simplex; disease eye herpes simplex; herpes simplex zoster; herpes labialis simplex; canker herpes simplex sore; herpes picture recurrent simplex; 6 herpes simplex