•The evolving epidemic of Human Immunodeficiency Virus type 1 in Sub-Saharan Africa and South Africa.•The impact of the epidemic on diagnostic algorithms.•2019 World Health Organisation's HIV testing guidelines.•Considerations for implementing the new HIV algorithm in South Africa. HIV-1/2 testing is the first step in ensuring HIV-infected individuals are diagnosed and appropriately managed. The impact of suboptimal HIV-1/2 testing algorithms significantly contributes to the increased rates of misdiagnosis of HIV infection. Recently, the World Health Organization (WHO) recommended that high burden countries revise their testing algorithm from a 2 to 3-test testing strategy in the context of an evolving HIV epidemic. Implementation of a new HIV-testing algorithm must be tailor-made within a national framework and must be balanced out with operational feasibility, patient outcomes, and cost-effectiveness. In this review, we provide an overview of the current state of the HIV epidemic and its impact on HIV testing, further we highlight areas of concern in changing from a 2-step to a 3-step test algorithm in the context of South Africa's HIV epidemic and public health program.