title: HIV type-1 group O infection in Gabon: low prevalence rate but circulation of genetically diverse and drug-resistant HIV type-1 group O strains.
abstract: The goals of this study conducted in Gabon were to determine the prevalence rate of HIV-1 group O (HIV-1/O) infections and to characterize the genetic diversity of HIV-1/O strains as well as implications on antiretroviral (ARV) drug resistance. During 2010-2011, 1,176 samples from HIV-positive subjects were tested at the CIRMF (Centre International de Recherches Médicales de Franceville) retrovirology laboratory using an in-house serotyping assay. Plasma HIV-1/O RNA viral loads (VL) were determined using the Abbott RealTime HIV-1 assay. After full genome sequencing, drug resistance patterns were analyzed using two different algorithms (Agence Nationale de Recherches sur le SIDA et les hépatites virales and Stanford). Overall, four subjects (0.34%) were diagnosed as HIV-1/O infected. One subject, untreated by ARVs, died 2 months after HIV-1/O diagnosis. One was lost to follow-up. Two additional patients, treated with nonnucleoside reverse transcriptase inhibitor (NNRTI)-based regimens, showed CD4 counts <200/mm(3) and VL results of 101,000 and 10,050 cp/ml. After full-length genome sequencing of these two strains, we found a wide range of natural polymorphism in the protease (≥15 substitutions) and gp41 (N42D mutation) genes, as well as in the gag and gag-pol cleavage sites. No resistance mutation was detected in the integrase gene. These two strains harbored the Y181C mutation making them resistant to NNRTIs. M41L, M184V, and T215Y mutations were also found for one strain, making it resistant to all NRTIs by the Stanford algorithm. Even if HIV-1/O infection is low in Gabon, an accurate diagnosis and a reliable virological follow-up are required in Central Africa to optimize ARV treatments of HIV-1/O-infected patients.
authors: Laboratoire de Rétrovirologie, CIRMF (Centre International de Recherches Médicales de Franceville), Franceville, Gabon.
authors: Florian
authors: F
authors: Liégeois
authors: Vanina
authors: V
authors: Boué
authors: Christelle
authors: C
authors: Butel
authors: Augustin
authors: A
authors: Mouinga-Ondémé
authors: Jeanne
authors: J
authors: Sica
authors: Chantal
authors: C
authors: Zamba
authors: Martine
authors: M
authors: Peeters
authors: Eric
authors: E
authors: Delaporte
authors: François
authors: F
authors: Rouet
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use; D024882:Drug Resistance, Viral / Q000235:genetics; D005260:Female; D005681:Gabon / Q000453:epidemiology; D014644:Genetic Variation; D016679:Genome, Viral; D015658:HIV Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000821:virology*; D015497:HIV-1 / Q000145:classification* / Q000187:drug effects / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010802:Phylogeny; D015995:Prevalence; D018894:Reverse Transcriptase Inhibitors / Q000627:therapeutic use
chemical_list: D019380:Anti-HIV Agents; D018894:Reverse Transcriptase Inhibitors