Trachoma is one of the world's most common causes of blindness. Between 10 and 15 percent of all people who lose their sight do so because of the disease. But as Rose Hoban reports, researchers are finding there are cheap, affordable ways to eradicate the disease in remote regions.

Nicole Stoller from the San Francisco, California-based Proctor Foundation explains that trachoma is a bacterial infection, spread widely from person to person by the Musca sorbens fly.

"One or two or even five infections isn't a particular problem," Stoller says. "But after repeated infections, what happens is that the eyelid begins to scar and it turns in, and the eyelashes scratch the cornea, ultimately causing blindness."

Stoller says one of the tragedies of trachoma is that it's easily treated with one dose of the antibiotic azithromycin - a pill that costs about 20 U.S. cents.

But unfortunately, a person can be easily reinfected. 

Stoller says researchers from her organization wanted to know what would happen if they tried to eradicate trachoma from an entire area. They focused on a remote region of Ethiopia called Gurage, where almost 80 percent of school-age children had evidence of current or recent infection.

"We looked at treating the entire community in order to reduce infection levels," she says. "[We were] going in day after day until we treated everybody in the community to see if that could potentially eliminate the infection rather than simply reducing it."

Stoller says they treated more than 90 percent of the residents in two villages - close to 800 people total. They gave each of them one dose of azithromycin every six months. After three years, there was no evidence of trachoma in either community.

"The only catch is that as soon as people start traveling out of the villages and coming back or have relatives visiting, there is always a chance to bring infection back in from somebody else, from outside sources," she says.

Stoller says to keep trachoma at bay, it would be necessary to treat surrounding communities as well.  She argues, however, that treatment done on a larger scale  could go a long way towards reducing the occurrence of blindness from trachoma.  While this would cost countries money in the short run, she says in the long run, it would reduce costs related to supporting people who have become blind from trachoma. 

Stoller presented her findings in October at the annual meeting of the American Public Health Association in San Diego, California.