A lab test used to diagnose conjunctivitis, popularly known as pink eye, is the conjunctival swab. The conjunctiva, a thin, transparent tissue that lies between the white of the eye and the inside of the eyelid, becomes inflamed and is known as conjunctivitis. Numerous factors, including germs, viruses, allergies, and excessive contact lens wear, can result in conjunctivitis. In youngsters and the elderly, bacterial conjunctivitis is most common. Both bacterial and viral infections are infectious yet treatable and do not have a catastrophic outcome. Conjunctivitis symptoms include burning and itchy eyes, copious tears, thick yellow discharge that crusts around the eyes, especially after a nap.