By Seppa, Nathan
Science News , Vol. 173, No. 8
Medicating an entire village twice a year can hamper a scourge that has blinded millions of people in developing countries, a study in Ethiopia shows.
The bacterial eye disease trachoma was wiped out in the United States and much of the industrialized world around the mid-20th century, thanks to improved hygiene, sanitation, and antibiotics. But the disease remains a problem in parts of Africa and Asia.
Trachoma often begins as minor itching called pinkeye. But repeated infections cause scarring of the inner eyelid. As the lids curl in, eyelashes rake the cornea, clouding it and leading to blindness.
In the new study, researchers targeted 16 villages in the impoverished Gurage region of Ethiopia where trachoma is rife. They used eyelid swabs to diagnose infections among preschool-aged children. After recording the infection rate, the scientists distributed the oral antibiotic azithromycin to everyone over 1 year of age. People in half the villages received a single annual dose while those in the others received a similar dose every 6 months.
After 2 years, the trachoma rate among preschoolers treated once annually had dropped from 43 percent to 7 percent. In villages where people got two doses a year, the rate plummeted even further--from 32 percent to less than 1 percent. The findings appear in the Feb. 20 Journal of the American Medical Association.
The bacterium Chlamydia trachomatis spreads by personal contact, sharing of towels, failure to wash the hands and face, and by flies and gnats. Preschoolers often carry high bacteria loads, making them efficient conveyors of infection. …