The Toto Bora trial tested whether a 5-day course of azithromycin reduced the risk of re-hospitalization or death in the 6 months following hospitalization among Kenyan children and found no overall benefit. We hypothesized that macrolide resistance in gut microbes could modify azithromycin’s effect. From June 2016 to November 2019, Kenyan children aged 1-59 months were enrolled at hospital discharge and randomized to azithromycin or placebo. DNA from fecal samples and E.
