Randomisation and masking
We used block-randomisation with variable block sizes, stratified by study site, to allocate participants (1:1:1) to either standard of care (no study antibiotic prescription), azithromycin (azithromycin 500 mg taken once per day for 3 days, from enrolment day, termed day 1), or amoxicillin (amoxicillin 1 g taken three times per day for 5 days, from day 1). An independent statistician prepared a randomisation list using the ralloc command in Stata. Allocations were sealed in sequentially numbered opaque envelopes, opened, and assigned by site staff upon confirming eligibility. The dosage of antibiotic groups and self-administration were explained, and participants took their first dose in the presence of study staff at the clinic with the remainder self-administered at home. The study was not blinded, but mycobacteriology and antimicrobial resistance outcome assessment occurred without reference to group.