Dr Ahmad Haeri Mazanderani talks about one of the most requested topics we've had for this year: "Does this patient have HIV? HIV false positives and false negatives". Ahmad is a clinical virologist in the Centre for HIV & STIs at the South African National Institute of Communicable Diseases, and a joint researcher in the Dept of Paediatrics & Child Health at Wits University. He uses two case examples to discuss the intricacies of how to diagnose elite controllers, post-treatment controllers, and HIV false positives.