Eye infections occur when microorganisms that are harmful to human such as bacteria, fungi and viruses invade different parts of the eye. They may affect either one eye or both eyes; they affect parts of the eyes from the eye lid to the cornea and can also affect the optic nerve. Some of the common symptoms are redness of the eye, irritation, itchiness, formation of crust around the eye, swelling of tissue around the eye, pain in the eye and discharge from the eye. Viral infection symptoms last for up to two weeks while those of bacterial infections clear quickly through use of antibiotic treatment.
Causes of eye infections include: ocular histoplasmosis syndrome, STIs such as chlamydia or gonorrhoea, herpes simplex virus, shingles, bacterial keratitis. Infections like conjunctivitis or keratitis are caused by: tuberculosis, Lyme disease, crab lice, mycosis, mumps, leprosy and STIs like hepatitis B or syphilis.
The various types of eye infections are conjunctivitis also known as pink eye; it is a contagious infection that affects children frequently. It is caused by a common cold virus referred to as adenovirus; viral conjunctivitis can be spread from the eye to the hands which will touch different surfaces which other people use. Infectious conjunctivitis is also caused by a bacteria referred to as staphylococcus aureus. Gonococcal and chlamydial conjunctivitis can be transmitted to an infant during birth, if the mother has any STD.
The other type of eye infection is viral keratitis which is of two types that is, fungal keratitis and Acanthamoeba keratitis, which invade mostly contact lens wearers since they can encounter parasites that invade the eyes. Trachoma is another eye infection related to Chlamydia trachomatis which can cause blindness and the infection is recurrent.
Endophthalmitis is a type of eye infection; the bacteria Endophthalmitis penetrate the interior part of the eye. Blindness may occur if not treated immediately via use of potent antibiotics, it can also occur due to an eye surgery like cataract surgery complication. Sty is also an eye infection that affects the interior portions of the upper and lower eye lid; it is characterized as a bump on the eyelid.