Final answer:
Foreign bodies can irritate or penetrate the eye, causing various inflammatory conditions such as conjunctivitis, keratitis, and dacryocystitis. Bacterial and viral infections, allergens, pollutants, and contact lens usage contribute to these conditions, with bacterial conjunctivitis being particularly contagious.
Step-by-step explanation:
Foreign bodies affect the eye in several ways including irritating the cornea and conjunctiva, becoming embedded in the cornea, or penetrating it. The conjunctiva is a frequent site of infection, and inflammation of the conjunctiva is known as conjunctivitis or commonly referred to as pinkeye. Infections of the eye can lead to a variety of conditions such as acute or chronic conjunctivitis, purulent discharge, blepharitis (inflammation of the eyelids), keratitis (inflammation of the cornea), keratoconjunctivitis (inflammation of both cornea and conjunctiva), and dacryocystitis (inflammation of the lacrimal sac).
There are different causes of these conditions, including bacterial or viral infections, allergens, pollutants, or contact lens use. Bacterial conjunctivitis, for example, is highly contagious and characterized by inflammation of the conjunctiva with a purulent discharge. It is usually self-limiting but sometimes treated with topical antibiotics. It is important when one suspects conjunctivitis, to seek medical attention promptly and discontinue the use of contact lenses. Parasitic infections such as Acanthamoeba keratitis and eye worm (Loiasis) can also affect the eye, leading to serious conditions that could impair vision.