Conjunctivitis is a common disease in ophthalmology, but its incidence has not yet been determined. Because most of the conjunctiva is in direct contact with the outside world, it is easily stimulated by infectious diseases (such as bacteria, viruses, chlamydia, etc.). ) and non-infectious factors (such as trauma, chemicals and physical factors, etc. ) In the surrounding environment, and the conjunctiva is rich in blood vessels and lymphoid tissues, it is easy to be sensitized by its own and external antigens. Conjunctivitis is a general term for the inflammatory reaction of conjunctiva caused by external factors and the body itself. Although conjunctivitis itself will not have a serious impact on vision, it will cause vision damage when its inflammation spreads to the cornea or causes complications. Changes such as conjunctival congestion, exudation, nipple hypertrophy and follicular formation caused by infection, allergy and trauma. The reasons can be divided into: ① Exogenous. Because the conjunctiva is exposed, it is easy to be stimulated by various microorganisms, wind dust, physical and chemical poisons and so on, resulting in inflammation. ② Endogenous. Pathogens infect conjunctiva through blood or lymph, or have allergic reactions to infections in other parts of the body. Inflammation can also spread directly from adjacent tissues. Conjunctivitis can be divided into bacterial, viral, chlamydial, fungal and allergic diseases according to the etiology. Its clinical manifestations are sudden conjunctival congestion, burning sensation, itching and excessive secretion, and general vision is not affected. Examination showed redness and swelling of eyelid, congestion of eyelid conjunctiva, hyperplasia of papilla follicles, congestion around bulbar conjunctiva, sometimes edema and subconjunctival hemorrhage, and secretion in conjunctival sac. To determine the source of the disease, it is necessary to do secretion smear for bacterial and cytological examination. Treatment should be based on local drug therapy for the cause. Conjunctivitis is an infectious eye disease caused by bacterial or viral infection. Whenever summer and autumn come, it is the epidemic season of this disease. Especially in some coastal cities, many people will suffer from acute conjunctivitis because the hot and humid weather is conducive to bacterial reproduction. Its onset is sudden and fierce, regardless of men, women and children. Once infected, it can occur within a few hours. It can break out in a certain range and affect people's health. Traditional Chinese medicine calls it "red eye in the sky" and common people call it "red eye". At the onset of this disease, there are photophobia, tears, tingling, thin secretion, swelling of eyelids and redness of conjunctiva due to vasodilation and bleeding. This is the origin of the name pink eye. If not treated in time, it will turn into chronic conjunctivitis. Antibiotic ointment or eye drops can generally be used to treat bacterial infections, and the symptoms generally disappear within 1 week after medication. Severe bacterial infection must be treated by oral antibiotics or antibiotic injection, and it usually takes 6 weeks to fully recover. If conjunctivitis is not treated, viral conjunctivitis can be recovered within 1 week. In order to alleviate the discomfort of children with allergic conjunctivitis, doctors will let them use anti-inflammatory eye drops. Usually, when parents find sticky pus on their children's eyelashes, they should wipe them clean with cotton soaked in cold boiled water. To prevent the spread of infection, wash your hands immediately after touching the infected part. Because viral conjunctivitis is particularly contagious, clothes and towels at home should not be washed together. If children with conjunctivitis can be treated immediately, the symptoms of infection at birth should disappear soon. Inflammatory or allergic conjunctivitis in older children rarely leads to lifelong vision problems.