Seroprevalence of human T-lymphotropic virus (HTLV) in blood donors in sub-Saharan Africa: a systematic review and meta-analysis

Background and objective Human T-cell lymphotropic viruses (HTLV) 1 and 2 are endemic in sub-Saharan Africa (SSA), transfusion-transmissible and causally linked to various severe diseases. However, even in SSA countries with moderate to high endemicity, routine blood donor screening for HTLV is rarely, if ever, performed. Information on seroprevalence is limited. The aim of this review is to establish the prevalence of HTLV-1 and HTLV-1/2 among blood donors in sub-Saharan Africa. Materials and Methods We systematically reviewed databases including EMBASE, MEDLINE and the Cochrane database library from their inception to June 2018. Studies presenting data on HTLV prevalence among blood donors in sub-Saharan Africa were included. A random-effect meta-analysis was conducted on all eligible studies. Results A total of 25 studies were included, representing 74 119 blood donors, of whom over 80% (61 002) were only tested for HTLV-1. The evidence base was high and moderate in quality. The pooled prevalence of the 17 studies that screened only for HTLV-1 and the nine studies that screened for HTLV-1/2 was 0 center dot 68 (95% CI: 0 center dot 29-1 center dot 60) and 1 center dot 11 (95% CI: 0 center dot 47-2 center dot 59) per 100 blood donors, respectively. Conclusion The prevalence of HTLV-1 infection among blood donors is relatively low. The current review is intended to inform debates and decisions about best practices to prevent transfusion-transmitted HTLV in sub-Saharan Africa. Further work is required to determine the risk of infections by transfusion and the cost-effectiveness of any new measures such as routine screening.