We conducted a randomized, double-blind placebo controlled, community trial in rural Bangladesh in children 4-59 mo of age to compare the efficacy of a 5- and 10-d course of zinc therapy on the incidence and duration of diarrhea over the subsequent 90-d follow-up after initial treatment for an acute childhood diarrheal (ACD) episode. Children (n = 1622) with ACD were randomly allocated to either 5 or 10 d of zinc treatment. Female field workers visited each child daily, supervised the administration of zinc, recorded the duration of current episode, and the occurrence and duration of diarrhea over the subsequent 3 mo. The incidence of diarrhea over the 90 d of follow-up did not differ between the 5-d (1.08 ± 1.38 episodes) and 10-d (1.02 ± 1.35 episodes) groups (P = 0.35). Children in both groups experienced a comparable duration of diarrheal episodes (3.1 ± 5.6 d vs. 2.9 ± 5.6 d, 5-d vs. 10-d, respectively; P = 0.64) with a mean difference between groups within the defined range of equivalence. Time to onset of the first episode and the proportion children experiencing diarrhea during the 90-d follow-up also did not differ between groups. These findings suggest that among Bangladeshi children, a 5-d zinc treatment for ACD is as efficacious as 10 d in preventing diarrhea in the subsequent 3 mo.
Trial registration: ClinicalTrials.gov NCT00325247.