Mass Antibiotic Treatment Doesn't Thwart Eye Disease

TUESDAY, March 7 (HealthDay News) -- A single mass antibiotic distribution is not an effective way to treat and eliminate trachoma -- an eye infection that can cause blindness -- in Ethiopian communities with high rates of the disease.

That's the conclusion of a study in the March 8 issue of the Journal of the American Medical Association.

Community-wide antibiotic distributions are part of the World Health Organization's strategy to eliminate trachoma as a public health concern by 2020. It has been suggested that a single mass antibiotic treatment in a community might eliminate trachoma. However, current WHO guidelines recommend three mass distributions per year.

To assess this approach, researchers monitored eight Ethiopian villages for up to 24 months after all residents over 1 year old were offered a single oral dose of the antibiotic azithromycin. Fifteen other villages were enrolled 12 months into the program.

The researchers, led by Jaya D. Chidambaram of the University of California, San Francisco, focused on children aged 1 to 5, because they have the highest rates of trachoma and may form the core group for transmission of the infection.

Prior to treatment, the average prevalence of infection in the children was 43.5 percent. By two months after the mass treatment, the rate was 5.1 percent. Two years after the treatment, the infection rate was 11.3 percent.

"Our results suggest that if infection is not eliminated by a single mass antibiotic treatment, then it predictably returns into the community, at least in this hyperendemic (area of high prevalence) area in 1- to 5-year-old children," the study authors wrote." However, infection comes back slowly and does not approach baseline prevalence even by two years."

They concluded that "repeated treatments or other measures will be necessary for elimination of infection, as recommended by WHO. A single treatment will not suffice."