Is mass azithromycin distribution to preschool-aged children effective in eliminating trachoma?
USA: Researchers in a recent study in JAMA Network Open have advised against administring targeted antibiotic treatments as an elimination strategy in areas with hypoendemic trachoma.
The findings of the trial showed that distributing biannual mass azithromycin to preschool-aged children was not more effective than a placebo, although there was a low underlying prevalence of trachoma. The sustained absence of trachoma even in the placebo group indicates that trachoma may have been eliminated as a public health problem.
Transmission of ocular strains of Chlamydia trachomatis is significant among preschool-aged children, considering this limiting the distribution of azithromycin to this age group may help in resource conservation and lead to less antimicrobial resistance, which is a potential advantage in areas with limited resources and hypoendemic trachoma.
Against the above background, Ahmed M. Arzika, The Carter Center, Niamey, Niger, and colleagues aimed to determine the efficacy of mass azithromycin distributions to preschool-aged children as a strategy for trachoma elimination in areas with a hypoendemic disease in a cluster randomized clinical trial performed from November 23, 2014, until July 31, 2017.
For this purpose, the researchers randomized thirty rural communities in Niger in a ratio of 1:1 to biannual mass distributions of either azithromycin or placebo to children aged 1 to 59 months. Data analysis was performed for trachoma outcomes from October 19, 2021, through June 10, 2022.
A single dose of either oral azithromycin (20 mg/kg using a height-based approximation for children who could stand or weight calculation for small children) or an oral placebo was given to all children (aged 1 to 59 months) every 6 months.
The study revealed the following findings:
- At baseline, 4726 children in 30 communities were included; 1695 children were enrolled in 15 azithromycin communities and 3031 children were enrolled in 15 placebo communities (mean proportions of boys, 51.8% vs 52.0%; mean age, 30.8 vs 30.6 months).
- The mean coverage of the study drug for the 4 treatments was 79% in the azithromycin group and 82% in the placebo group.
- The mean prevalence of trachomatous inflammation–follicular at baseline was 1.9% in the azithromycin group and 0.9% in the placebo group.
- At 24 months, trachomatous inflammation–follicular prevalence was 0.2% in the azithromycin group and 0.8% in the placebo group.
"The low trachoma levels in the study area made it difficult to determine whether azithromycin distributions targeted to preschool-aged children could be an effective elimination strategy for trachoma in areas with hypoendemic infection," the researchers wrote.
They conclude, "the findings of this 2-year, placebo-controlled trial indicate that in the Boboye and Loga departments of Niger, trachoma has been eliminated as a public health problem and there is a necessity for ongoing trachoma interventions."
Reference:
Arzika AM, Mindo-Panusis D, Abdou A, et al. Effect of Biannual Mass Azithromycin Distributions to Preschool-Aged Children on Trachoma Prevalence in Niger: A Cluster Randomized Clinical Trial. JAMA Netw Open. 2022;5(8):e2228244. doi:10.1001/jamanetworkopen.2022.28244
