Mass Antibiotic Program Can Offer Trachoma Herd Protection
Success against eye disease offers strategy for other bacterial diseases with no effective vaccine
FRIDAY, March 27 (HealthDay News) -- Herd immunity to trachoma can be achieved through repeated rounds of mass antibiotic administration to children, who are a core means of transmission for the eye disease, according to a report published in the March 28 issue of The Lancet.
Jenafir I. House, of the University of California San Francisco, and colleagues conducted a study of 4,764 children aged 1 to 10 years in 12 areas of Amhara, Ethiopia, who were randomized to receive a single dose of azithromycin four times a year, and 6,014 children in another 12 areas whose treatment was delayed until after the study.
At the 12-month mark, the investigators analyzed 637 children aged 1 to 10 years, and 561 adults and children aged 11 years and older within the children-treated group, and 618 and 550, respectively, in the control group. In children, the mean prevalence of infection went from 48.4 to 3.6 percent. In the untreated age group of 11 years and older, the mean prevalence of infection in the untreated age group was 47 percent lower than at baseline, and 35 percent lower than seen in untreated communities.
"If ocular chlamydial infection can be eliminated by targeting treatment to less than a third of the population, this approach could provide a realistic long-term strategy for trachoma programs," the authors write. "It also offers a strategy for eradication of an infectious disease for which an effective vaccine is not available."