Herpes Simplex Virus

Herpes Simplex Virus (HSV) infection is a common viral mucocutaneous disease affecting the lips, oral cavity, and perioral tissues. It typically presents as painful papulovesicular lesions that rupture and ulcerate before healing.

Following primary infection—usually acquired during childhood—the virus remains latent in sensory nerve ganglia, particularly the trigeminal ganglion, and may reactivate periodically, resulting in recurrent disease.

Two major types exist:

• HSV-1 – predominantly oral and facial infections

• HSV-2 – mainly genital infections (though overlap occurs)

Primary infection commonly involves the gingiva, palate, and oral mucosa, while recurrent infections usually affect the vermillion border of the lips (herpes labialis).

Pathophysiology

HSV infection occurs through:

1. Direct contact with infected saliva or lesions

2. Viral replication in epithelial cells

3. Local cell destruction leading to vesicle formation

After primary infection:

• Virus migrates via sensory nerves

• Establishes lifelong latency in trigeminal ganglion neurons

• Reactivation occurs due to triggering factors

Common Reactivation Triggers

• Fever (“fever blisters”)

• Emotional stress

• Sunlight exposure

• Trauma or dental procedures

• Immunosuppression

• Hormonal changes

• Fatigue or systemic illness

Reactivation results in viral replication and transport back to skin or mucosa causing recurrent lesions.

Risk Factors

• Childhood exposure to HSV

• Immunocompromised states (HIV, malignancy)

• Malnutrition

• Stress

• Fever or systemic infections

• Excess ultraviolet exposure

• Local trauma

• Poor oral hygiene

Signs and Symptoms

Primary Herpetic Gingivostomatitis

(Common in children)

• Fever

• Malaise

• Painful oral ulcers

• Gingival inflammation

• Drooling

• Difficulty eating or swallowing

• Cervical lymphadenopathy

Recurrent Herpes Labialis

• Burning or tingling sensation

• Local pain

• Clustered vesicles on erythematous base

• Ulceration after vesicle rupture

• Crusting and healing without scarring

Diagnostic Criteria

Diagnosis is mainly clinical.

Typical progression:

1. Prodrome:

   • Tingling

   • Warmth

   • Itching

2. Within ~12 hours:

   • Local erythema

3. Lesion evolution:

   • Papules → Vesicles → Ulcers → Crusting → Healing

Duration:

• 5–12 days (average 7 days)

Investigations

Usually not required in uncomplicated cases.

Indicated when:

• Severe disease

• Immunocompromised patient

• Atypical presentation

• Neonatal infection suspected

Possible tests:

• Viral PCR (gold standard)

• Viral culture

• Tzanck smear

• Serology (limited diagnostic value)

Management

HSV infection is generally self-limiting, but treatment reduces:

• Pain

• Viral shedding

• Duration of symptoms

• Recurrence severity

Non-Pharmacological Management

• Maintain adequate hydration

• Avoid salty, spicy, or acidic foods/drinks

• Maintain oral hygiene

• Avoid touching or picking lesions

• Apply petroleum jelly to prevent cracking

• Avoid kissing or sharing utensils during active lesions

• Identify and control triggering factors

Pharmacological Management

1. Herpes Labialis

• Acyclovir cream applied every 4 hours for 5 days

Best initiated during prodromal phase.

2. Herpetic Stomatitis

• Acyclovir 200 mg orally every 6 hours for 5 days

AND

• Topical acyclovir cream twice daily for 5 days

3. Immunocompromised Patients

Higher viral replication risk:

• Acyclovir 400 mg orally five times daily for 5 days

Longer therapy may be required.

4. Oral–Facial Herpes Zoster (Differential Treatment)

• Acyclovir 400–800 mg orally five times daily for 5 days

5. Pain Control

• Paracetamol 1 g orally every 8 hours for 3 days

OR

• Diclofenac 50 mg orally every 8 hours for 3 days

OR

• Ibuprofen 400 mg orally every 8 hours for 3 days

Avoid NSAIDs in contraindicated patients.

Special Populations

Children

• Risk of dehydration due to painful swallowing.

• Encourage fluids and soft diet.

Immunocompromised Patients

• Risk of:

  • Disseminated infection

  • Chronic ulcers

  • Systemic involvement

Require early antiviral therapy.

Pregnancy

• Oral HSV generally low fetal risk.

• Active genital HSV near delivery requires obstetric evaluation.

Complications

• Secondary bacterial infection

• Dehydration (children)

• Herpetic whitlow

• Herpetic keratitis (ocular emergency)

• Eczema herpeticum

• Disseminated HSV infection

• Encephalitis (rare but life-threatening)

Differential Diagnosis

• Aphthous ulcers

• Angular cheilitis

• Impetigo

• Hand-foot-mouth disease

• Varicella-zoster infection

• Contact dermatitis

Prevention

• Avoid direct contact with active lesions

• Do not share utensils, towels, or cosmetics

• Use lip sunscreen (UV protection)

• Maintain immune health

• Stress management

• Early antiviral therapy during prodrome

• Hand hygiene after touching lesions

For frequent recurrences:

• Suppressive antiviral therapy may be considered under specialist care.

Prognosis

• Lesions heal spontaneously within 7–10 days

• Recurrences decrease with age

• Lifelong latency persists

• Early antiviral therapy improves outcomes

Patient Education

Patients should understand that:

• HSV infection is lifelong but controllable.

• Recurrences are common.

• Early treatment during tingling phase shortens illness.

• Lesions are contagious until crusted.