Short communication: Population-based surveillance of HIV-1 drug resistance in cameroonian adults initiating antiretroviral therapy according to the world health organization guidelines

With ongoing earlier enrollment on and rapid scale-up of antiretroviral therapy (ART) in Cameroon, there are increasing risks of transmitted HIV drug resistance (HIVDR) at population levels. We therefore evaluated the threshold of HIVDR in a population initiating ART, in order to inform on the effectiveness of first-line regimens, considering HIV-1 diversity, plasma viral load (PVL) and CD4-based disease progression. A total of 53 adults (median [Interquartile range, IQR] CD4: 162 cell/mm3 [48-284]; median [IQR] PVL: 5.34 log10 RNA [4.17-6.42] copies/ml) initiating ART in 2014 at the Yaoundé Central Hospital were enrolled for HIV-1 protease-reverse transcriptase sequencing. Drug resistance mutations (DRMs) were interpreted using the 2009 World Health Organization (WHO) list versus the Stanford HIVdb algorithm version 7.0. Level of DRMs was low (3.77%) versus moderate (7.55%) respectively following the WHO list (T69D, K103N) versus Stanford HIVdb (T69D, A98G, K103N, K238T), respectively. Prevailing clade was CRF02_AG (71.70%). Based on Stanford HIVdb, a slightly higher proportion of patients with DRMs was found among ones infected with CRF02_AG than in those non-CRF02_AG infected (7.89% versus 6.67%, p=1.000), with lower-PVL (7.69% <5.5 versus 0% ≥5.5 log10 RNA copies/ml, p=0.488) and with higher-CD4 counts (9.52% CD4 ≥200 versus 3.33% CD4 <200 cells/mm3, p=0.749). Thresholds of DRMs suggest that standard first-line regimens currently used in Cameroon may remain effective at population levels, despite scale-up of ART in the country, pending adherence and closed virological monitoring. With an intent-to-diagnose approach, the discrepant levels of DRMs support using Stanford HIVdb to evaluate initial ART, while revising the WHO list for surveillance.