West SK, Bloch E, Weaver J, et al. - In view of the lack of understanding concerning the mechanisms underlying the finding of reduced child mortality in communities with biannual treatment with azithromycin, researchers investigated whether morbidity differs in a cohort of children aged 1–36 months, residing in communities randomized to biannual treatment of preschool-aged children with azithromycin or placebo. They randomly assigned 30 villages in Kilosa, Tanzania to receive biannual treatment of all children aged 1–59 months with either azithromycin (20/mg/kg single dose) or placebo. They observed a statistically significant decline over time in reported cough among children residing in the azithromycin communities, but not in the placebo communities. Once adjusting for clustering and age, no significant difference was evident in decline between the 2 treatment arms. This suggests no beneficial effect of azithromycin treatment on morbidity outcomes at biannual surveys.