Effect of Azithromycin on the Ocular Surface Microbiome of C
The aim of this study was to evaluate the effect of the 4 times per year mass azithromycin distributions on the ocular surface microbiome of children in a trachoma endemic area.

In this cluster-randomized controlled trial, children aged 1 to 10 years were randomized to either no treatment or treatment with a single dose of oral azithromycin every 3 months for 1 year. Post hoc analysis of ocular surface Chlamydia trachomatis load, microbial community diversity, and macrolide resistance determinants was performed to evaluate differences between treatment arms.

--1255 children from 24 communities were included in the study. The mean azithromycin coverage in the treated communities was 80%.

--The average age was 5 years. Ocular surface C. trachomatis load was reduced in children treated with the 4 times per year azithromycin.

--Neisseria gonorrhoeae, Neisseria lactamica, and Neisseria meningitidis were more abundant in the no-treatment arm compared with the treated arm.

--The macrolide resistance gene ermB was not different between arms, but mefA/E was increased in the azithromycin-treated arm.

Conclusively, a reduction in the load of C. trachomatis and 3 Neisseria species in communities treated with azithromycin was found. These benefits came at the cost of selection for macrolide resistance.

Source: https://journals.lww.com/corneajrnl/Abstract/9000/Effect_of_Azithromycin_on_the_Ocular_Surface.95667.aspx