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Orolabial herpes (gingivostomatitis) is the most prevalent form of mucocutaneous herpes infection; 35 to 60 percent of persons in the United States show serologic evidence of having been infected by HSV-1. Overall, the highest rate of infection occurs during the preschool years. Female gender, history of sexually transmitted diseases and multiple sexual partners are risk factors.

Clinical presentation

Primary herpetic gingivostomatitis usually affects children under the age of five. It typically takes the form of painful vesicles and ulcerative erosions on the tongue, palate, gingiva, buccal mucosa and lips. Edema, halitosis and drooling may be present, and tender submandibular or cervical lymphadenopathy is common.

Systemic symptoms include fever (38.4 to 40E°C [101 to 104E°F]), malaise and myalgia. The duration of the illness is two to three weeks, and oral shedding of virus may continue for as long as 23 days.

Recurrences typically occur two or three times a year. The duration is shorter and the discomfort less severe than in primary infections. UV radiation may trigger recurrence of orolabial HSV-1.

Treatment of primary infection

Topical acyclovir has not proved to accelerate healing. Topical penciclovir ( Denavir), applied every two hours for four days, reduces clinical healing time by one day.

Oral acyclovir, in a dosage of 200 mg five times daily for five days, accelerates loss of crusts by one day in adults and can reduce the mean duration of pain by 36 percent. Acyclovir decreases the duration of oral lesions in primary infection from 10 days to four days. Standard analgesic therapy with acetaminophen or ibuprofen should also be advised.

Treatment of recurrent infection

Oral acyclovir (400 mg bid) is effective in reducing by 50 to 78 percent the frequency of herpes labialis. Oral acyclovir lessens the severity of lesions when they occur. Short-term prophylactic therapy (400 mg bid) with acyclovir may be desirable in some patients who anticipate intense exposure to UV light (eg, skiers, or in those who work outdoors) or before special occasions, such as a wedding.

Famciclovir (Famvir), in a dosage of 250 mg tid for five days, accelerates healing time from 5.8 days to 3.0 days.

Patient counseling

Patients should be warned about HSV autoinoculation from one body site to another. Infected areas should be patted dry rather than wiped dry. Sunscreen and lip balm are recommended to reduce recurrent disease.

Patients should abstain from sexual activity while lesions are present. Use of latex condoms is encouraged because of asymptomatic viral shedding.

The risk of neonatal transmission must be explained to the patient.

Recommended testing includes evaluation for gonorrhea, chlamydia, syphilis, genital warts, and human immunodeficiency virus (HIV).
Anti-Herpes medications

Genital HSV infection is usually transmitted through sexual contact. About 21.9 percent of all persons in the United States 12 years of age or older have serologic evidence of HSV-2 infection. Risk factors include multiple sexual partners, increasing age, female gender, low socioeconomic status and human immunodeficiency virus (HIV) infection.

Clinical presentation

Primary genital herpes has an incubation period of two to 12 days, with a mean of four days, followed by a prodrome of itching, burning or erythema. Multiple transient, painful vesicles then appear on the penis, perineum, vulva, vagina or cervix, and tender inguinal lymphadenopathy may follow. The initial ulceration crusts and heals by 14 to 21 days. Systemic symptoms include fever, headache, malaise, abdominal pain and myalgia. Recurrences are usually less severe and shorter in duration than the initial outbreak.

Approximately 90 percent of those infected are unaware that they have herpes infection and may unknowingly shed virus and transmit infection.

Treatment of primary infection

Zovirax is effective in reducing symptoms. The oral acyclovir dosage for treatment of primary genital herpes is 400 mg PO tid or 200 mg five times daily for 10 days. Intravenous administration may be required in immunocompromised patients and those with severe disseminated infection. Topical acyclovir is much less effective than oral or intravenous acyclovir.

Valtrex, 400 mg PO tid, is indicated for the treatment of primary genital herpes but costs more than acyclovir.

Famvir, 250 mg PO tid for 7-10 days, is as effective as acyclovir in the treatment of initial genital herpes infection, although it may be twice as expensive.

Treatment of recurrent infection

Recurrences of herpes are often mild and infrequent. Drug therapy to prevent recurrences is reserved for patients who have more than six outbreaks per year.

Acyclovir (Zovirax) has been used to suppress recurrences of genital herpes, decreasing the frequency by as much as 80 percent.

Famciclovir and valacyclovir are as effective as acyclovir in suppressing recurrent genital herpes. Valacyclovir has the advantage of once-daily dosing. Famciclovir must be given twice daily to be effective.

Episodic therapy is intended to diminish symptoms and infectivity during recurrences. Acyclovir, taken within minutes to hours after the prodrome of recurrence begins, exerts a minimal benefit in recurrent genital herpes infections. Famciclovir and valacyclovir are slightly more effective for the treatment of recurrent infections.
Herpes treatment

Herpes simplex virus (HSV) affects more than one-third of the world’s population. HSV exists as types 1 and 2, which have affinities for different body sites. Ninety percent of infections caused by HSV-2 are genital, and 90 percent of those caused by HSV-1 are oral.

Diagnosis

The diagnosis of genital HSV infection may be made clinically, but laboratory confirmation is recommended in patients presenting with primary or suspected recurrent infection. The gold standard of diagnosis is viral isolation by tissue culture, although this process can take as long as four to five days, and the sensitivity rate is only 70 to 80 percent. Viral culture is still the diagnostic test of choice for HSV skin infections.

Polymerase chain reaction enzyme-linked immunosorbent assay (PCR-ELISA) is extremely sensitive (96 percent) and specific (99 percent) but expensive. For this reason, it is not used for the diagnosis of skin lesions but is the test of choice for diagnosing HSV encephalitis.

Antiviral medications

Acyclovir is an acyclic guanosine analog. Oral bioavailability is only 15 to 30 percent. The dosage must be adjusted in patients with renal failure. Acyclovir is a safe and extremely well-tolerated drug. Toxicity is rare, but in patients who are dehydrated or who have poor renal function, the drug can crystallize in the renal tubules, leading to a reversible creatinine elevation or, rarely, acute tubular necrosis. Adverse effects, usually mild, include nausea, vomiting, rash and headache.

Valtrex is the l-valine ester prodrug of acyclovir. It has an oral bioavailability three to five times greater than that of acyclovir, and it is safe and well tolerated.

Famciclovir is the oral form of penciclovir, a purine analog similar to acyclovir. Oral bioavailability is 77 percent. Mechanism and efficacy are similar to those of acyclovir.