Macrolide Resistance in MORDOR I — A Cluster-Randomized Trial in Niger

To the Editor: Mass administration of azithromycin reduced childhood mortality in the trials MORDOR (Macrolides Oraux pour Rduire les Dcs avec un Oeil sur la Rsistance) I 1,2 and MORDOR II (conducted by Keenan et al., published in this issue of the Journal 3 ). However, antibiotic resistance remains a major concern, and MORDOR I did not include assessments of morbidity. We randomly selected 3371 children aged 1 to 59 months from the same pool of 30 Nigerien communities involved in MORDOR I (Fig. The children were randomly assigned to receive either azithromycin or placebo, which were distributed twice a year over 2 years, as in MORDOR I (for details, see the protocol, available at NEJM.org). The mean (SD) coverage with azithromycin and placebo was 798% and 826%, respectively. Ethical approval was obtained from the University of California, San Francisco, Committee for Human Research and the Ethics Committee of the Niger Ministry of Health. We obtained oral consent from guardians before treatment and before collection of nasopharyngeal and rectal swabs. No incentives were offered. All analyses were conducted at the community level.