Objectives: HIV infection in the Central African Region is old and driven by several genetic variants. We analyzed the prevalence of transmitted HIV drug resistance at a population level within fifteen years that can provide information on the effectiveness of first line antiretroviral therapy (ART) in Cameroon.
Methods: HIV-1 protease and reverse transcriptase sequences from Cameroon were obtained from the HIV Sequence Database of the LANL (194) and the CIRCB patient database (126) (from 1995 to 2010) and analyzed for drug resistance mutations and genotype using the Calibrated Population Resistance (CPR) tool of the Stanford University HIV Drug Resistance Database. Of these 320 sequences, 181 were collected from 1995 to 2002 (Group 1) and 139 from 2003 to March 2010 (Group 2). The sequences were classified at that point in time regardless of treatment history of the individual.
Results: Within Group 1, M184V (5.6%), Y181C (6.1%) and M46I (98.3%) were the most frequent mutations, seven (3.9%) showed a 3-class resistance, implying that majority of these sequences would show low-level resistance. Within Group 2, 16.3%, 63.7% and 65.9% had mutations associated to PI, NRTI and NNRTI resistance, respectively, 58.5% for NRTI and NNRTI, and 8.1% for the 3 drug classes. The most frequent DRM identified in Group 2 were M184V (62.2%), K103N (38.5%) and M46I/L (14.3%). Three of the new WHO-approved mutations, I85V in one sequence in Group 1, and L76V (2.9%) and V179F (0.7%) in Group 2 were identified. CRF02_AG was most prevalent within both Groups.
Conclusion: The frequency of mutations at position 46 is fading, while at positions 184 and 103 it is increasing within the population. These results indicate an urgent need to evaluate the Guidelines for first line ART in Cameroon as part of the ART scaling-up process.