Overview

Conjunctivitis is one of the most common eye conditions worldwide, affecting people of all ages but particularly prevalent in children. The condition causes the blood vessels in the conjunctiva to become inflamed, making them more visible and giving the eye its characteristic pink or red appearance. While often uncomfortable and unsightly, most cases of conjunctivitis are relatively mild and resolve without causing permanent damage to vision.

There are three main types of conjunctivitis: viral, bacterial, and allergic. Viral conjunctivitis is the most common form, often occurring alongside upper respiratory infections. Bacterial conjunctivitis typically produces more discharge and can be more severe. Allergic conjunctivitis is triggered by allergens and often occurs seasonally or in response to specific environmental factors. Each type requires different treatment approaches, making proper diagnosis essential.

The highly contagious nature of viral and bacterial conjunctivitis makes it a significant public health concern, particularly in schools, daycare centers, and other communal settings. The condition can spread rapidly through direct contact with infected eye secretions or contaminated objects. Understanding the signs, symptoms, and proper hygiene measures is crucial for preventing transmission and managing outbreaks effectively.

Symptoms

The symptoms of conjunctivitis can vary depending on the underlying cause, but certain signs are common across all types. Recognition of these symptoms is important for early treatment and prevention of spread.

Primary Eye Symptoms

  • Eye redness - The hallmark sign, caused by dilated blood vessels in the conjunctiva
  • White discharge from eye - Varies from watery to thick and purulent depending on the cause
  • Pain in eye - Usually mild discomfort, burning, or gritty sensation
  • Itchiness of eye - Particularly prominent in allergic conjunctivitis
  • Lacrimation - Excessive tearing as the eye attempts to flush out irritants
  • Swollen eye - Puffiness of eyelids and surrounding tissue

Associated Systemic Symptoms

  • Sore throat - Common with viral conjunctivitis
  • Cough - Often accompanies viral forms
  • Nasal congestion - Particularly with allergic or viral types
  • Fever - More common in bacterial infections
  • Coryza - Nasal inflammation with discharge

Type-Specific Symptoms

Viral Conjunctivitis:

  • Watery discharge
  • Often starts in one eye, spreads to other
  • Light sensitivity
  • Associated cold symptoms
  • Swollen lymph nodes near ears

Bacterial Conjunctivitis:

  • Thick, yellow-green discharge
  • Eyes stuck together upon waking
  • More severe redness
  • Often affects both eyes
  • Possible ear infection in children

Allergic Conjunctivitis:

  • Intense itching
  • Clear, watery discharge
  • Both eyes affected simultaneously
  • Seasonal pattern
  • Associated allergic symptoms (sneezing, runny nose)

Causes

Conjunctivitis can be caused by various factors, each requiring different management approaches. Understanding the underlying cause is essential for appropriate treatment and prevention of spread.

Viral Causes

  • Adenovirus - Most common viral cause, highly contagious
  • Herpes simplex virus - Can cause severe keratitis
  • Varicella-zoster virus - Associated with chickenpox or shingles
  • Enterovirus - Can cause epidemic hemorrhagic conjunctivitis
  • Measles virus - Part of measles infection
  • COVID-19 - Can present with conjunctivitis

Bacterial Causes

  • Staphylococcus aureus - Common in adults
  • Streptococcus pneumoniae - Common in children
  • Haemophilus influenzae - Particularly in children
  • Moraxella catarrhalis - More common in colder months
  • Chlamydia trachomatis - Can cause inclusion conjunctivitis
  • Neisseria gonorrhoeae - Causes severe hyperacute conjunctivitis

Allergic Causes

  • Seasonal allergens - Pollen from trees, grasses, weeds
  • Perennial allergens - Dust mites, pet dander, mold
  • Contact allergens - Cosmetics, contact lens solutions
  • Medications - Eye drops, systemic medications
  • Environmental irritants - Smoke, pollution, chlorine

Other Causes

  • Chemical irritants - Chlorine, smoke, fumes
  • Foreign bodies - Dust, debris in the eye
  • Contact lens-related - Poor hygiene, overwear
  • Blocked tear ducts - In newborns
  • Autoimmune conditions - Sjögren's syndrome, rheumatoid arthritis

Risk Factors

Several factors increase the likelihood of developing conjunctivitis. Understanding these risks helps in prevention and early intervention.

Environmental Risk Factors

  • Close contact with infected individuals - Schools, daycare, households
  • Crowded living conditions - Dormitories, military barracks
  • Poor hygiene practices - Infrequent handwashing
  • Sharing personal items - Towels, pillowcases, cosmetics
  • Swimming pools - Inadequately chlorinated water
  • Seasonal exposure - High pollen counts

Personal Risk Factors

  • Contact lens use - Especially with poor hygiene
  • Recent upper respiratory infection - Increases viral risk
  • Allergic conditions - Hay fever, asthma, eczema
  • Weakened immune system - HIV/AIDS, chemotherapy
  • Chronic dry eye - Reduced natural defense
  • Previous eye surgery or injury - Altered eye surface

Age-Related Factors

  • Children - Higher risk due to close contact in schools
  • Newborns - Risk of neonatal conjunctivitis
  • Elderly - Weakened immune response
  • College students - Communal living increases exposure

Occupational Risks

  • Healthcare workers - Exposure to infected patients
  • Teachers and childcare workers - Contact with children
  • Laboratory workers - Chemical exposure
  • Agricultural workers - Allergen and irritant exposure

Diagnosis

Diagnosis of conjunctivitis typically begins with a comprehensive eye examination and patient history. While most cases can be diagnosed clinically, laboratory tests may be necessary in severe or atypical cases.

Clinical Examination

  • Visual inspection - Assessment of redness, discharge, swelling
  • Visual acuity test - To rule out vision impairment
  • Slit lamp examination - Detailed view of eye structures
  • Fluorescein staining - To detect corneal involvement
  • Eyelid eversion - Check for foreign bodies or papillae
  • Lymph node palpation - Preauricular nodes in viral cases

Patient History

Important questions include:

  • Duration and onset of symptoms
  • Type and amount of discharge
  • Associated symptoms (fever, URI symptoms)
  • Contact with infected individuals
  • Recent travel or swimming
  • Contact lens use
  • Allergies and medications
  • Previous episodes

Laboratory Tests

When indicated for severe or atypical cases:

  • Bacterial culture - Identifies causative organism
  • Viral culture or PCR - For suspected viral causes
  • Gram stain - Rapid bacterial identification
  • Giemsa stain - For chlamydial inclusion bodies
  • Immunofluorescence - Specific viral identification
  • Allergy testing - For recurrent allergic cases

Differential Diagnosis

Conditions that may mimic conjunctivitis:

  • Keratitis (corneal infection)
  • Uveitis (inflammation of uvea)
  • Acute angle-closure glaucoma
  • Episcleritis or scleritis
  • Blepharitis (eyelid inflammation)
  • Dry eye syndrome
  • Foreign body

Treatment Options

Treatment of conjunctivitis depends on the underlying cause. While viral conjunctivitis typically resolves on its own, bacterial and allergic forms may require specific medications.

Viral Conjunctivitis Treatment

  • Supportive care - Primary approach as most cases self-resolve
  • Artificial tears - Lubricates and soothes irritation
  • Cold compresses - Reduces swelling and discomfort
  • Antihistamine drops - For associated itching
  • Antiviral medications - Reserved for herpes simplex cases
  • Avoid antibiotics - Ineffective against viruses

Bacterial Conjunctivitis Treatment

Topical Antibiotics:

  • Broad-spectrum drops - Polymyxin B/trimethoprim, fluoroquinolones
  • Antibiotic ointments - Erythromycin, bacitracin
  • Treatment duration - Usually 5-7 days
  • Severe cases - May require systemic antibiotics
  • Gonococcal conjunctivitis - Requires immediate systemic treatment

Allergic Conjunctivitis Treatment

  • Allergen avoidance - Primary prevention strategy
  • Antihistamine drops - Olopatadine, ketotifen
  • Mast cell stabilizers - Cromolyn sodium
  • Combination drops - Antihistamine/mast cell stabilizer
  • Topical NSAIDs - For severe inflammation
  • Topical corticosteroids - Short-term for severe cases
  • Oral antihistamines - For systemic allergic symptoms

General Supportive Measures

  • Warm compresses - For bacterial conjunctivitis
  • Cool compresses - For viral and allergic types
  • Eyelid hygiene - Gentle cleaning with warm water
  • Avoid contact lenses - Until infection clears
  • Replace eye cosmetics - To prevent reinfection
  • Sunglasses - For light sensitivity

Prevention of Spread

  • Frequent handwashing
  • Avoid touching eyes
  • Don't share personal items
  • Stay home from work/school when contagious
  • Properly dispose of tissues
  • Clean surfaces regularly

Prevention

Preventing conjunctivitis involves good hygiene practices and avoiding known triggers. These measures are particularly important in preventing the spread of infectious forms.

Personal Hygiene

  • Hand hygiene - Wash hands frequently with soap and water
  • Avoid eye touching - Minimize hand-to-eye contact
  • Personal items - Don't share towels, pillowcases, or cosmetics
  • Tissue use - Use once and dispose properly
  • Face washing - Clean face and eyelids daily

Contact Lens Care

  • Follow proper cleaning and storage protocols
  • Replace lenses as recommended
  • Never sleep in lenses unless approved
  • Avoid wearing during eye infections
  • Use fresh solution daily
  • Replace lens cases every 3 months

Environmental Measures

  • Allergen control - Use air filters, keep windows closed during high pollen
  • Swimming precautions - Wear goggles, avoid poorly maintained pools
  • Workplace safety - Use protective eyewear when needed
  • Home cleanliness - Regular cleaning of surfaces
  • Bedding hygiene - Wash pillowcases frequently

Community Prevention

  • Stay home when contagious
  • Notify close contacts of infection
  • School/daycare policies for exclusion
  • Proper chlorination of swimming pools
  • Healthcare worker hand hygiene

When to See a Doctor

While many cases of conjunctivitis resolve without medical intervention, certain symptoms warrant immediate medical attention.

Seek Immediate Medical Care For:

  • Moderate to severe eye pain
  • Significant vision changes or loss
  • Intense light sensitivity
  • Copious purulent discharge
  • Signs of corneal involvement
  • No improvement after 24 hours of treatment
  • Symptoms in newborns

Schedule an Appointment If:

  • Symptoms persist beyond 1 week
  • Recurrent episodes occur
  • Contact lens wearer with red eye
  • History of eye surgery or trauma
  • Weakened immune system
  • Symptoms worsen despite treatment

High-Risk Groups

These individuals should seek medical care promptly:

  • Newborns and infants
  • Contact lens wearers
  • Immunocompromised patients
  • Those with chronic eye conditions
  • Recent eye surgery patients

Related Conditions

Several conditions may occur alongside or be mistaken for conjunctivitis:

References

  1. Azari AA, Arabi A. (2023). Conjunctivitis: A Systematic Review. Journal of Ophthalmic & Vision Research.
  2. American Academy of Ophthalmology. (2023). Conjunctivitis Preferred Practice Pattern.
  3. Centers for Disease Control and Prevention. (2023). Conjunctivitis (Pink Eye) Guidelines.
  4. Varu DM, et al. (2022). Conjunctivitis Preferred Practice Pattern. Ophthalmology.
  5. WHO. (2023). Priority Eye Diseases: Conjunctivitis. World Health Organization.