HIV-1 subtypes and drug resistance mutations among female sex workers varied in different cities and regions of the Democratic Republic of Congo.

BACKGROUND

Complex mosaic structures of HIV-1 were found in the Democratic Republic of Congo (DRC). Currently, there is limited information on the circulating HIV-1 strains, the distribution of these strains and antiretroviral (ART) resistant viruses in different regions of the country, and the HIV-1 strains harbored by the high-risk groups like female sex workers (FSW) reported to be the source of recombinant and ART resistant viruses.

METHODS

Dried Blood Spots (DBS), collected from 325 infected FSWs in ten cities from 2012 DRC HIV/STI Integrated Biological and Behavioral Surveillance Survey, were tested for HIV-1 genotypes and antiretroviral resistance mutations. Regional segregation of HIV-1 clades was detected using phylogenetics. The significance for differences in HIV-1 subtype and drug resistance mutations were evaluated using Chi-square tests.

RESULTS

There were 145 (env) and 93 (pol) sequences analyzed. Based on env sequences, the predominant subtype was A1 (44%), and recombinants as defined pol sequences comprised 35% of the total sample. Paired sequences of pol and env from DRC FSW revealed mosaic recombinant in 54% of the sequences. Distinct geographic distributions of different HIV-1 subtypes and recombinants were observed. Subtype A1 was prevalent (40%) in Goma located in the East and significantly higher than in Mbuji-Mayi (p<0.05) in the South-central region, or in Lubumbashi in the South. Antiretroviral resistance was detected in 21.5% of 93 pol sequences analyzed, with the M184I/V and K103N mutations that confer high-level resistance to NRTI and NNRTI, respectively, being the most frequent mutations. However, the K103N mutant viruses were found only in the East.

CONCLUSION

HIV-1 variants found in DRC FSW reflect those reported to circulate in the general population from the corresponding geographical locations. HIV-1 mosaic genetics were readily detected in FSW. Importantly, ART resistance mutations to NNRTI and NRTI were common in the DRC sex workers.