WEDNESDAY, April 23 (HealthDay News) -- In communities with moderate levels of the eye disease trachoma, one or two rounds of high coverage mass treatment with the antibiotic azithromycin may be sufficient to eliminate the infection, researchers say.

A team at the London School of Hygiene & Tropical Medicine's Trachoma Group said its findings challenge the World Health Organization's recommendation for annual antibiotic treatment and called for a re-evaluation of how communities affected with trachoma are treated.

The five-year study was conducted in Kahe Mpya, Tanzania. After an initial round of mass treatment (97.6 percent of residents) with single-dose azithromycin, the prevalence of trachoma decreased from 9.5 percent to 0.1 percent after two years.

A second round of mass treatment was carried out two years after the first round. Three years after the second round of mass treatment, trachoma DNA was not detected in the eyes of any of the 859 people who were checked, which suggested the infection had been eliminated.

A letter outlining the findings was published in the April 24 issue of the New England Journal of Medicine.

Currently, the WHO recommends three years of annual mass azithromycin treatment before reassessment in communities where 10 percent or more of children ages 1 to 9 have trachoma.

"Had WHO recommendations on antibiotic use been followed, three or possibly six annual rounds of mass treatment would have been offered in this community, whereas our data suggest that one round was sufficient," noted Dr. Anthony Solomon, lead author of the letter. "The less antibiotic we can use in each community, the more people we'll be able to use donated antibiotic for, and the lower the likelihood of the emergence of antibiotic-resistant strains."