CAST-NET:

The CAST- NET study is a multi-year observational programmatic study that sought to evaluate the effectiveness of South Africa's national cryptococcal antigen (CRAG) screening and pre-emptive treatment programme, in order to improve HIV care and survival of persons living with advanced HIV disease.

In CAST-NET Part 1, we conducted a retrospective cohort study of approximately 3000 CRAG-positive participants (who screened positive in 2017-2019 in 27 sub-districts) and used retrospective record review and several other routine data sources to document the clinical care of participants and their 6-month outcomes. The Division partnered with Epicentre Health Research to collect data at facilities. A team of medical officers in the Division completed data abstraction for just over 2000 patient records.

Part 2 of the CAST-NET study, implemented for 6 months during 2021 consisted of a pragmatic cluster-randomized trial, with the aim of assessing whether a health systems intervention at healthcare facility level (mediated through informal appointment of a ”Crypto Champion” at each facility could improve follow-up and initiation of pre-emptive fluconazole therapy among newly-diagnosed persons with antigenaemia. We also compared 6-month cryptococcal meningitis-free survival among people with antigenaemia at intervention versus control facilities.