Napoleon's troops encountered it in Egypt in 1798. It blinded early Americans, and was one of the most common causes for rejecting would-be immigrants to the US at Ellis Island. With improved sanitation, trachoma was eliminated from North America and Europe. But the disease remains the world's leading preventable cause of blindness, infecting 150 million people in developing countries. Repeated infections over the years scar the upper eyelid, eventually causing the thin tissue to recede so that the eyelashes literally scratch the cornea, and in many cases cause blindness.
Some people wear tweezers around their necks to pluck the painful lashes, but they can grow back.
Painful treatment Since the 1950s, treatment has meant applying an ointment of the antibiotic tetracycline directly to the eyes twice a day for six weeks. Now Pfizer-sponsored studies show that one dose of oral Zithromax, widely used to fight other infections, works just as well. Teaching children to wash their faces. Distribution of Zithromax. Water sanitation programmes.