Common eye infections are conjunctivitis, or pinkeye, and sties, which are bacterial infections, according to MedlinePlus. Dacryocystitis — an infected tear duct — also causes problems, states Bausch & Lomb.
Conjunctivitis is typically a bacterial or viral infection of the conjunctiva, the membrane that coats the eyelid and eye, explains Bausch & Lomb. Some people develop the condition because of allergies or in reaction to environmental chemicals. Symptoms include tearing, yellowish discharge, and eye discomfort, itching or burning.
A stye develops when skin bacteria enters an eyelash follicle, MedlinePlus states. A pimple-like bump develops at the eyelash root, says Bausch & Lomb. This lump sometimes swells until it breaks open and drains. Symptoms of dacryocystitis include red eyes, extreme tearing and discharge. Adults develop this condition when a tear duct become blocked, but many infants are born with a tear duct membrane that is unopened or too small.