 In total, 400 children aged 6-16 years, living with HIV and diagnosed with CLD will be enrolled at Harare Children s Hospital in Harare Zimbabwe and Queen Elizabeth Central Hospital in Blantyre Malawi. These will receive weekly treatment with azithromycin or placebo during 12 months. Another 100 children 50 per site living with HIV but with no CLD will be enrolled as a comparison group for laboratory sub-studies. 