The impact of Option B+ on mother-to-child transmission of HIV in Africa: A systematic review

Objective: In 2015, the WHO released new guidelines to reduce mother-to-child transmission (MTCT) of HIV. The recommendations, known as Option B+, included initiation of lifelong highly active antiretroviral therapy regardless of CD4 count for all HIV-positive pregnant and breastfeeding mothers. For infants, exclusive breastfeeding for 6 months and antiviral therapy were sanctioned. Targets of <5% transmission in breastfeeding populations and <2% in non-breastfeeding populations were set. This review evaluated the impact of Option B+ on MTCT in African countries. Methods: Using the PRISMA guidelines, a systematic search of PubMed and Google Scholar databases was conducted to identify relevant studies published between 2015 and 2021. All studies meeting inclusion criteria were evaluated. Results: Of the 687 references screened, 22 studies from 11 countries (Cameroon, Ethiopia, Lesotho, Malawi, Rwanda, South Africa, Swaziland, Tanzania, Uganda, Zambia and Zimbabwe) met inclusion criteria. Six studies reported MTCT rates of <2%, 16 studies reported rates of 2–5% and two studies (Uganda and Zambia) reported 6% or more. Rates varied within the same study at different time points postpartum and amongst studies from the same country. Overall, reported MTCT rates appear to be close to WHO targets. However, diverse study designs, selection bias, extensive loss to follow-up and undocumented adherence rates to Option B+ protocols may significantly underestimate MTCT rates of HIV in Africa. Conclusions: Standardised protocols for impact evaluation must be established to provide evidenced-based data on the efficacy of Option B+ in Africa.