Infection With Human T-Lymphotropic Virus 1 (HTLV-1) in Ivory Coast

Human T-lymphotropic virus 1 (HTLV-1) is a retrovirus that originally jumped from Asian and African monkeys to humans. Africa is the world region with the largest population infected with HTLV-1. However, most data about HTLV-1 infection rates in endemic African countries are scarce and old. A rapid test for HTLV antibodies (Assure HTLV-I/II, MP Biomedicals, Singapore) was used for screening blood collected from pregnant women and persons living with HIV (PLwH) who consecutively attended a large outpatient clinic in Yamoussoukro, the capital of Ivory Coast, during the summer of 2025. A total of 102 pregnant women and 206 PLwH were examined. All were of black ethnicity. The mean age was 24 years old for pregnant women and 45 years old for PLwH. Up to 74% of the latter were female. Only two women, one coinfected with HIV and another pregnant, were HTLV seroreactive and confirmed as HTLV-1 positive by Inno-LIA. Viral sequences from the HIV/HTLV-1 coinfected female phylogenetically belonged to the HTLV-1a subclade TC, clustering with Middle East strains. The current rate of HTLV-1 infection amongst pregnant women and PLwH living in the central Ivory Coast is below 1%.