Herpes Simplex

Herpes simplex virus (HSV) is a common infection that occurs sub-clinically in about 85% of patients. In the rest, it causes localized lesions. HSV may be latent for years, but after the initial infection, the patient becomes a carrier susceptible to recurrent attacks. The outbreaks may be provoked by fever, menses, stress, heat, cold, lack of sleep, sun exposure, and contact with reactivated disease (for example, by kissing or by sharing cosmetics). In recurrent infections, the patient usually has no constitutional signs and symptoms.

HSV infection generally isn't serious in an otherwise healthy adult; in a neonate or an immunocompromised patient, such as one with acquired immunodeficiency syndrome (AIDS), it can produce severe illness. In fact, serious HSV infections occur commonly in patients with AIDS.

HSV infection occurs worldwide and equally in males and females. Lower socioeconomic groups are infected more often, probably because of crowded living conditions.

Causes

Herpes virus hominis, a widespread infectious agent, causes two serologically distinct HSV types. Type 1 (HSV-1) is transmitted primarily by contact with oral secretions. It mainly affects oral, labial, ocular, or skin tissues. Type 2 (HSV-2), transmitted primarily by contact with genital secretions, mainly affects genital structures. Infection with HSV-1 occurs more frequently and earlier in life than infection with HSV-2. More than 90% of adults have antibodies to HSV-1 by age 40; in lower socioeconomic groups, most persons acquire HSV-1 infection before age 20. Antibodies to HSV-2 aren't routinely detected before puberty.

Although HSV most frequently occurs in the structures mentioned, it may infect any epithelial tissue. The incubation period varies, depending on the infection site. The average incubation for infection is 1 to 26 days.

Signs and symptoms

Some children and adults never experience any symptoms with the first attack; others have severe flu-like symptoms and ulcers in and around the mouth. The following are the most common symptoms of cold sores. However, each child may experience symptoms differently. Symptoms may include:

• tingling of the lips
• a small blister or cluster of blisters on the lips and mouth that enlarge, burst, then crust over
• itching and irritation of the lips and mouth
• soreness of the lips and mouth that may last from three to seven days

The symptoms of cold sores may resemble other dermatologic conditions or medical problems. Always consult your children's physician for a diagnosis.

Diagnostic tests

To diagnose any form of herpes, your doctor will study your medical history and perform a physical examination. Laboratory tests, such a viral cultures and blood tests, can be performed to determine the type of virus causing the symptoms.

Treatment

Symptomatic and supportive therapy is the rule. Generalized primary infection usually requires antipyretic and analgesic medications to reduce fever and pain. Anesthetic mouthwashes, such as viscous lidocaine, may reduce the pain of gingivostomatitis, enabling the patient to consume food and fluids and thus promote hydration. (Avoid offering alcohol-based mouthwashes, which can increase discomfort.) A bicarbonate-based mouth rinse may be used for oral care. Drying agents, such as calamine lotion, may soothe labial and skin lesions. Avoid using petrolatum-based salves or dressings because they promote viral spread and slow healing.

Refer patients with eye infections to an ophthalmologist. Topical corticosteroids are contraindicated in active infection, but ophthalmic medications, such as idoxuridine, trifluridine, and vidarabine, may be effective.

Acyclovir is a major agent for combating genital herpes, particularly primary infection. Other medications include ganciclovir, famiciclovir, and valacyclovir. The drug may reduce symptoms, viral shedding, and healing time. And although it's mostly ineffective in treating recurrent attacks, it may be prescribed to treat and suppress HSV in immunocompromised patients and those with severe and frequent recurrences. The drug is available in topical, oral, and I.V. form (usually reserved for severe infection).

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.