# Oral Viral Infections Pathology

> Oral viral infections for NEET-MDS Oral Pathology: HSV, VZV, Coxsackie, EBV and HPV lesions, Tzanck cells, Cowdry inclusions and drug therapy.

- Canonical URL: https://prepelephant.com/topics/neet-mds/oral-pathology/oral-viral-infections-pathology-mds
- Exam / course: NEET-MDS · Subject: Oral Pathology
- Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team
- First published: 2026-10-02
- Last updated: 2026-10-02
- How to cite: "Oral Viral Infections Pathology", PrepElephant, https://prepelephant.com/topics/neet-mds/oral-pathology/oral-viral-infections-pathology-mds

## Direct answer

Ballooning degeneration of keratinocytes, multinucleated epithelial giant cells and eosinophilic intranuclear inclusions (Cowdry type A) are the shared histological signature of the herpesviruses attacking oral mucosa — HSV types 1 and 2 and varicella-zoster virus — while the clinical pictures separate them: primary herpetic gingivostomatitis (fever plus vesicles and ulcers of a child, self-limiting in 10-14 days), recurrent herpes labialis (the UV- and fever-triggered cold sore of the vermilion), and trigeminal zoster with dermatomal pain and vesicles. The picornaviruses arrive as Coxsackie syndromes — herpangina (posterior palatal vesicles in a summer-month child) and hand-foot-mouth disease (anterior lesions plus extremity rash); Epstein-Barr virus drives infectious mononucleosis and hairy leukoplakia; human papillomaviruses produce squamous papilloma, verruca vulgaris, condyloma and focal epithelial hyperplasia (Heck disease). Therapy is acyclovir-family antivirals early in HSV and VZV, supportive care for Coxsackie disease, and antiretroviral resolution for hairy leukoplakia.

## What you must remember

- **Primary herpetic gingivostomatitis:** HSV-1 in children; fever, cervical lymphadenopathy, vesicles on gingiva, tongue and palate breaking to shallow ulcers, anterior gingiva prominently involved; self-limiting 10-14 days; hydration, analgesia, acyclovir if early or severe; highly contagious.
- **Recurrent HSV:** latency in the trigeminal ganglion; reactivation triggers — ultraviolet light, fever, menstruation, immunosuppression; tingling prodrome, then clustered vesicles at the vermilion border or intraoral fixed keratinised sites; acyclovir or valacyclovir within the prodrome.
- **VZV:** primary varicella with oral vesicles alongside the exanthem; reactivation as unilateral, dermatomal, painful trigeminal zoster; nasal-tip vesicles (Hutchinson sign) threaten the eye; Ramsay Hunt syndrome adds ear vesicles and facial palsy; treat early with high-dose valacyclovir.
- **Histology (all herpesviruses):** intraepithelial vesicle with acantholysis, balloon degeneration, multinucleated giant cells with moulded nuclei, and Cowdry type A intranuclear inclusions — a guaranteed identification question.
- **Coxsackieviruses:** herpangina (group A) — sudden fever with posterior vesicles on soft palate and tonsillar pillars, summer-autumn, pre-school children; hand-foot-mouth disease — anterior oral ulcers plus palmar and plantar vesicles; both self-limiting; Kerala epidemics documented.
- **EBV:** infectious mononucleosis (fever, lymphadenopathy, atypical lymphocytes, positive heterophile antibody, palatal petechiae); hairy leukoplakia — corrugated lateral-tongue plaque in immunosuppression, not premalignant, resolving with antiretrovirals; links with endemic Burkitt lymphoma and nasopharyngeal carcinoma.
- **HPV-associated benign lesions:** squamous papilloma (HPV 6/11), verruca vulgaris (HPV 2/4, skin-to-mouth), condyloma acuminatum (HPV 6/11), and focal epithelial hyperplasia or Heck disease (HPV 13 and 32); managed by excision or laser.
- **Measles and mumps:** Koplik spots (bluish-white-centred buccal macules of the measles prodrome) and mumps parotitis (paramyxovirus, bilateral painful parotid swelling).

## A typical clinical sorting exercise

Three children arrive in one clinic week, and the examiner expects them sorted without laboratory help. A two-year-old with high fever, drooling and clustered ulcers on tongue, palate and crusted gingiva: primary herpetic gingivostomatitis — supportive care, hydration, acyclovir if within 72 hours. A six-year-old in June with abrupt fever, refusal to swallow and vesicles confined to the soft palate and tonsillar fossae: herpangina — posterior location plus season decides; no antiviral needed. A four-year-old with anterior oral ulcers plus palmar and plantar vesicles: hand-foot-mouth disease. Now a 60-year-old with diabetes on steroids develops unilateral vesicles and severe maxillary-division pain: zoster — urgent ophthalmology review if the nose tip is involved (Hutchinson sign), immediate high-dose antiviral. None of these needs biopsy — but the HIV-positive patient with a non-wipeable corrugated lateral-tongue plaque does: hairy leukoplakia, EBV-driven, a CD4 surrogate, resolved by antiretroviral therapy rather than excision.

## Where students slip

The herpangina versus hand-foot-mouth confusion is the most reliable trap: herpangina is posterior (soft palate, pharynx) without skin lesions; hand-foot-mouth is anterior plus extremity rash — location is the entire question. Second, recurrent intraoral herpes recurs only on keratinised fixed mucosa (hard palate, attached gingiva), which separates it from aphthae in a single line. Third, Tzanck multinucleated cells are credited to pemphigus by the unwary; in the smear context they belong to HSV and VZV. Fourth, hairy leukoplakia is mislabelled premalignant and confused with candidiasis — it will not wipe off, is EBV-positive, and carries no malignant potential. Finally, Koplik spots are mixed up with Fordyce granules; the bluish-white dot on an erythematous base opposite the molars, in a febrile child with catarrhal symptoms, is the exam picture.

## Frequently asked questions

### Which histological features are shared by HSV and VZV lesions?

Intraepithelial vesicles with ballooning degeneration, acantholysis, multinucleated giant cells with moulded nuclei and eosinophilic Cowdry type A intranuclear inclusions.

### How do herpangina and hand-foot-mouth disease differ?

Both are Coxsackievirus infections, but herpangina causes posterior oropharyngeal vesicles without skin involvement, while hand-foot-mouth disease causes anterior oral ulcers plus palmar and plantar vesicles.

### What triggers recurrent herpes labialis?

Reactivation of latent HSV-1 in the trigeminal ganglion by ultraviolet light, fever, respiratory infection, menstruation, trauma or immunosuppression, typically preceded by a tingling prodrome.

### What is oral hairy leukoplakia and what causes it?

An EBV-driven corrugated white plaque on the lateral tongue border in immunosuppressed (classically HIV-positive) patients — not premalignant, not removable, resolving with antiretroviral therapy.

### Which HPV types cause focal epithelial hyperplasia?

HPV types 13 and 32, producing multiple flat papules (Heck disease), reported in Indian kindreds.