Difference Between Viral and Bacterial Pink Eye

Both viruses and bacteria can cause pink eye. Conjunctivitis, uveitis, irits, elevated pressure in the eye, as well as sinusitis, can also cause pink eye. The commonest cause of pink eye is conjunctivitis. Conjunctivitis can be due to viruses, bacteria, allergies, or chemicals. Allergic conjunctivitis is an abnormal hyper-sensitive reaction to a normal substance in the environment. There is a history of asthma, drug or food allergy in these patients. Avoiding allergens, anti-histamines, and steroids are effective in treating allergic conjunctivitis. Chemicals cause irritation if they get into the eye accidentally. Eye should be washed thoroughly with clean running water and covered, and the patient should rush to a hospital. Potent irritants like acids and bases can burn the eye and blind the patient permanently. If the pain increases while looking at a bright light (Photophobia), attention should be paid to exclude uveitis, elevated eye pressure, and meningitis. Photophobia is not prominent in conjunctivitis.

Viral Pink Eye

Viral conjunctivitis is caused by viruses that cause upper respiratory tract infections. Therefore, it accompanies common cold, sinusitis, and throat inflammation. It features excessive production of tears, itching, pain and blurred vision sometimes. Usually it starts on one side and spreads to the other. Diagnosis is clinical. Antiviral drugs are indicated in severe cases only. It is self-limiting. Supportive treatments and good hygiene are often enough. It spreads rapidly. Proper hand washing, personal eating utensils, cups, towels and handkerchiefs limit spreading.

Bacterial Pink Eye

Bacterial pink eye sets in rapidly. It features redness of eye, excessive tearing, pain, blurring of vision, and yellowish discharge. Eye lids stick together due to yellowish eye discharge. Eye and surrounding area may crust over. Some patients feel like there is something in the eyes because of the irritation caused by the discharge. It starts in one eye and usually spreads to the other within a week. Staphylococci and Streptococci are the usual culprits. While these organisms cause more redness, Chlamydia does not cause much redness. In Chlamydial conjunctivitis, false membranes are formed on the surface of the eyes and under the eyelids. Bacterial conjunctivitis can be confirmed by taking a swab for culture. Doctors prescribe antibiotics and pain killers without waiting for reports usually.

Viral vs Bacterial Pink Eye

• Viral conjunctivitis does not usually appear alone while bacterial conjunctivitis can be the sole presenting condition.

• Viral conjunctivitis accompanies upper respiratory tract infections.

• Both bacterial and viral pink eye spread by contact.

• Viral conjunctivitis causes soreness of eyes and tearing while bacterial conjunctivitis in addition causes a thick, yellow, purulent discharge.

• There are no crusting or stuck eye lids in viral conjunctivitis while pus may stick the eyelids together in bacterial conjunctivitis.

• There is no pseudo membrane formation in viral conjunctivitis while Chlamydiae, Gonorrhea and Diphtheriae form a false membrane over the true membrane covering the eye and eyelids.

• Viral pink eye is self-limiting and does not need treatment most of the time. Bacterial pink eye may need topical antibiotic eye drops.