Mass azithromycin distributions are used to clear ocular strains of chlamydia that cause trachoma, but treatments may also affect respiratory infections, diarrhea, and malaria. Here, we monitor a large cohort in which almost 90% of individuals received azithromycin. We assess whether receiving treatment is associated with reduced all-cause and infectious childhood mortality.

As part of a clinical trial for trachoma, a census was conducted in 24 communities in rural Ethiopia. All individuals ≥1 year of age were eligible for single-dose oral azithromycin, although antibiotic coverage was not universal. A follow-up census was performed 26 months after treatment to estimate all-cause mortality among children 1-5 years of age, and verbal autopsies were performed to identify infectious mortality.

The cohort included 35,052 individuals ≥1 year of age and 5507 children 1-5 years of age, of whom 4914 received a dose of azithromycin. All-cause mortality was significantly lower among those 1-5-year-old children who received azithromycin (odds ratio [OR]=0.35 [95% confidence interval {CI}, 0.17-0.74]), as was infectious mortality (OR=0.20 [95% CI, 0.07-0.58]). When individuals were compared only with members of the same household, azithromycin treatment was still associated with reduced all-cause mortality in children 1-5 years of age (OR=0.40 [95% CI, 0.16-0.96]), although this relationship was not statistically significant for infectious mortality (OR=0.35 [95% CI, 0.10-1.28]).

This study demonstrated an association between mass oral azithromycin treatment and reduced all-cause and infectious childhood mortality. This relationship could not be attributed to bias at the level of the household. Mass azithromycin distributions may have benefits unrelated to trachoma.