Alarming rate of transmitted drug resistance mutations and genetic diversity in newly HIV-1-infected patients in Benin

Abstract Background Seventeen years after the start of the IBAARV (Beninese initiative for access to antiretrovirals), transmitted drug resistance mutations in ARV naïve patients and HIV-1 genetic diversity were investigated in Benin. Methods 353 plasma samples were collected between October and December 2017 in nineteen facilities care in Benin from HIV-1 positive and ARV naive individuals. Pol (protease + partial RT) region was amplified and sequenced in 248 samples. Results Drug resistance mutations were detected in (27/248; 10.9%) according to the WHO SDRM 2009 list, with predominance of mutations directed to NNRTIs drugs (24/248; 10%).Phylogenetic and recombination analyses showed a predominance of CRF02_AG strains (165/248; 66.5%) and a high genetic diversity with five other variants and 39 URFs (15.7%) which contained portions of strains that co-circulate in Benin. Eight recent transmission chains revealed active ongoing transmission of HIV-1 strains among ARV naïve patients. Conclusions Our study showed a high primary drug resistance rate and a complex genetic diversity. Regular monitoring of primary drug resistance is required to adapt HIV-1 treatment strategies and adoption of new WHO recommendations in Benin.