Most types of conjunctivitis do not normally last for extended periods of time. Inclusion conjunctivitis is sometimes referred to as long term conjunctivitis. This type of conjunctivitis is caused by strains of the Chlamydia trachomatis bacteria. The eye becomes infected most commonly by genital secretions from someone with Chlamydia coming in contact with the eye.

The Chlamydia bacterium causes a bacterial infection of the conjunctiva, the outer membrane of the eye and the surface underneath the eyelids. A newborn may develop inclusion conjunctivitis after birth if the mother has Chlamydia. The actual conjunctivitis occurs five to fourteen days after birth. In newborns, inclusion conjunctivitis can cause significant swelling of the eyelids. It is often prevented in newborns by applying erythromycin ointment on the eyes immediately after birth.

In adults, inclusion conjunctivitis can be from poorly-chlorinated hot tubs, swimming pools, direct contact with genital secretions, or sharing contaminated makeup. Inclusion conjunctivitis can cause bumps inside the lower eyelid and pus-like discharge that can be sticky and stringy. It often only affects one eye. Unlike most forms of conjunctivitis, inclusion conjunctivitis can cause permanent damage to the cornea. It can cause the formation of new blood vessels, called neovascularization, and a clouding of the cornea.

At first, inclusion conjunctivitis may be mistaken for bacterial conjunctivitis. If the antibiotic treatment for bacterial conjunctivitis fails to cure the pink eye, the doctor may look for causes of the long term conjunctivitis. For a definitive diagnosis, the doctor must take a sample of the discharge from the eye. Laboratory testing of the discharge can help diagnose the conjunctivitis and indicate which antibiotic will be most effective in treating the pink eye. Adults who are diagnosed with inclusion conjunctivitis are tested for Chlamydia and treated if they have the infection.

Newborns with inclusion conjunctivitis are treated with oral erythromycin and tetracycline ointment to the eyes. If left untreated, the conclusion conjunctivitis lasts three to twelve months. Any permanent damage to the eyes from conclusion conjunctivitis in adults and newborns is irreversible. Treatment helps prevent the permanent eye damage.

Adults with inclusion conjunctivitis are often treated with tetracycline ointment to be applied to the eyes. An oral antibiotic is also prescribed. Someone with inclusion conjunctivitis may need frequent medical checkups to determine if the conjunctivitis is responding to treatment. The parents of a newborn who develops inclusion conjunctivitis is treated for Chlamydia. Chlamydia is not the only sexually transmitted disease that can cause potentially serious conjunctivitis.