Which is the most common cause of viral conjunctivitis?

BTSC 3 August 2025

Medical & Surgical Nursing

Easy

Appeared in: BTSC 3 August 2025

Explanation

Adenovirus is the most frequent cause of viral conjunctivitis, responsible for 65-90% of all cases.
It typically presents with acute onset of a watery or serous discharge, red eye, and a gritty or foreign body sensation.
Key clinical signs associated with adenoviral conjunctivitis include a follicular reaction of the palpebral conjunctiva and tender preauricular lymphadenopathy.
Some strains of adenovirus can cause more severe forms like epidemic keratoconjunctivitis (EKC) or pharyngoconjunctival fever (PCF).

Option A: While Herpes simplex virus (HSV) can cause viral conjunctivitis, it is a much less common cause compared to adenovirus.
Option B: Enterovirus (specifically Enterovirus 70 and Coxsackievirus A24) is a primary cause of Acute Hemorrhagic Conjunctivitis (AHC), a specific and highly contagious form of conjunctivitis that often occurs in epidemics.
Option D: Varicella-zoster virus (VZV) is not a common cause of isolated viral conjunctivitis. It typically causes conjunctivitis as part of a systemic infection.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Etiology of Viral Conjunctivitis as background academic context rather than a clinical decision trigger.
Recognizing that adenovirus is the most common cause of viral conjunctivitis is crucial because it underscores the importance of infection control. Viral conjunctivitis is highly contagious and can spread rapidly through direct contact in households, schools, and healthcare settings.
A nurse's primary role is patient education on hygiene: strict handwashing, not sharing personal items (towels, pillows, makeup), and avoiding touching the eyes to prevent transmission to the other eye or to other people.
What if? If a patient presented with a thick, purulent, yellow-green discharge and their eyelids were matted shut in the morning, the most likely cause would be bacterial, not viral. The management would then shift from supportive care to considering topical antibiotic therapy.

How to Approach the Question

First, identify the core of the question: it asks for the 'most common cause' of a specific condition, 'viral conjunctivitis'. This is a factual recall question.
Access your knowledge base regarding common infectious pathogens for eye infections.
Evaluate each option based on its prevalence. Adenovirus is widely known as the primary pathogen for 'pink eye' or viral conjunctivitis.
Consider the other options as potential but less common causes. Associate HSV with vesicles/ulcers, Enterovirus with hemorrhagic conjunctivitis, and VZV with chickenpox/shingles.
Select the pathogen that accounts for the vast majority of cases, which is Adenovirus.

Concept Tested & Keywords

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