HIV type 1 subtype C and CB Pol recombinants prevail at the cities with the highest AIDS prevalence rate in Brazil

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A Restriction Enzyme Based Cloning Method to Assess the In vitro Replication Capacity of HIV-1 Subtype C Gag-MJ4 Chimeric Viruses
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A Restriction Enzyme Based Cloning Method to Assess the In vitro Replication Capacity of HIV-1 Subtype C Gag-MJ4 Chimeric Viruses

Published on: August 31, 2014

Luis F M Brígido1, Cynara C Nunes, Cristina M Oliveira

  • 1Laboratório de Retrovírus, Instituto Adolfo Lutz, São Paulo, SP, Brazil. lbrigido@ial.sp.gov.br

AIDS Research and Human Retroviruses
|December 28, 2007
PubMed

Insights

Human Immunodeficiency Virus type 1 (HIV-1) clade C and CRF31 recombinants are now twice as common as clade B in Brazil. Primary drug resistance mutations were found in 8.3% of cases, predominantly to NNRTIs.

Area of Science:

  • Virology
  • Epidemiology
  • Public Health

Background:

  • Human Immunodeficiency Virus type 1 (HIV-1) clade B is historically dominant in Brazil.
  • Increasing reports of HIV-1 clade C in southern Brazil, with many samples identified as a recombinant form (CRF31) containing a B segment in the reverse transcriptase region.

Purpose of the Study:

  • To analyze HIV-1 clades, recombination patterns, and primary drug resistance mutations (DRMs) in samples from three Brazilian cities with high AIDS prevalence.
  • To estimate HIV incidence using a BED assay and investigate associations between clade C and recent infections.

Main Methods:

  • Analysis of 209 HIV RNA partial polymerase sequences to determine HIV clades and recombination patterns.
  • Identification of primary drug resistance mutations (DRMs).
  • Estimation of HIV incidence using the BED assay.

Main Results:

  • HIV-1 clade C and CRF31 patterns were twice as frequent as clade B across all studied sites.
  • Significant variations in the proportion of clade C and CRF31 patterns were observed among different sites.
  • HIV incidence was estimated at 2.6 persons-years in Santa Catarina (SC).
  • No association was found between clade C and recent or younger infections.
  • Surveillance DRMs were detected in 8.3% of cases, primarily against non-nucleoside reverse transcriptase inhibitors (NNRTIs).
  • HIV-1 clade F pol genomes exhibited a significantly higher prevalence of primary DRMs.

Conclusions:

  • HIV-1 clade C and CRF31 are emerging as significant viral patterns in Brazil, challenging the historical dominance of clade B.
  • The distribution of these clades varies geographically within Brazil.
  • A notable prevalence of primary drug resistance mutations, particularly to NNRTIs, necessitates ongoing surveillance.
  • Further research is needed to understand the epidemiological dynamics and clinical implications of these evolving HIV-1 strains in Brazil.

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