Near full genome characterization of HIV-1 unique recombinant forms in Cameroon reveals dominant CRF02_AG and F2 recombination patterns.

INTRODUCTION: In Cameroon, a manifold diversity of HIV strains exists with CRF02_AG and unique recombinant forms (URFs) being the predominant strains. In recent years, a steady increase in URFs and clade F2 viruses has been monitored through partial genome sequencing. There is an information gap in the characterization of emerging URFs along the full genome, which is needed to address the challenges URFs pose towards diagnosis, treatment and HIV-1 vaccine design. METHOD: Eighteen Cameroonian URFs from samples collected between the years 2000 and 2015 were studied using a newly developed near full genome sequencing (NFGS) protocol based on variable nested RT-PCRs with a versatile primer set. Near full genomes were characterized for recombination patterns and sequence signatures with possible impact on antiretroviral treatment or Env-directed immune responses. Third-generation sequencing (3GS) of near full or half genomes (HGs) gave insight into intra-patient URF diversity. RESULTS: The characterized URFs were composed of a broad variety of subtypes and recombinants including A, F, G, CRF01_AE, CRF02_AG and CRF22_01A1. Phylogenetic analysis unveiled dominant CRF02_AG and F2 recombination patterns. 3GS indicated a high intra-patient URF diversity with up to four distinct viral sub-populations present in plasma at the same time. URF pol genomic analysis revealed a number of accessory drug resistance mutations (DRMs) in the ART-naïve participants. Genotypic env analysis suggests CCR5 usage in 14/18 samples and identified deviations at residues, critical for gp120/gp41 interphase and CD4 binding site broadly neutralizing antibodies in more than half of the studied URFs. V1V2 sites of immune pressure in the human RV144 vaccine study varied in more than a third of URFs. CONCLUSIONS: This study identified novel mosaic patterns in URFs in Cameroon. In line with the regional predominance of CRF_02AG and the increased prevalence of clade F2, prominent CRF_02AG and F2 background patterns were observed underlying the URFs. In the context of the novel mosaic genomes, the impact of the identified accessory DRMs and Env epitope variations on treatment and immune control remains elusive. The evolving diversity of HIV-1 URFs in Cameroon requires continuous monitoring to respond to the increasing challenges for diagnosis, antiretroviral treatment and prevention.

HIV and tuberculosis co-infection in a highly HIV-infected population of rivers state, Nigeria.

Human Immunodeficiency Virus (HIV) and tuberculosis (TB) are considered as key players in the global health scene. This study sought to determine the prevalence of TB among HIV-positive attendees of the Directly Observed Treatment of Short Course (DOTS) program at the military hospital in Port Harcourt. The association of HIV prevalence with gender and age as risk factors was also determined. A total of 200 patients aged 15-65 years were screened. Re-screening for HIV was done for confirmation. The overall prevalence for anti-TB antibodies amongst HIV-positive individuals was 14.0% (7.5% in males and 6.5% in females) while HIV prevalence following re-screening was 92%. It was observed that based on employment status and level of education, the highest HIV prevalence was seen in unemployed individuals and individuals with no formal education. The result showed that 29.9% of the HIV seropositives were males while 70.1% were females. Sex-related prevalence of HIV-TB coinfection within groups indicated significantly higher co-infection rates (P < 0.05) among males (23.1%) than females (9.6%). Age-related prevalence of HIV-TB coinfection within groups showed that co-infection was significantly greater (P < 0.05) in ages below 30 years (21.2%) than in their counterparts 30 years and above (9.6%). This study confirmed the presence of TB co-infections among HIV-positive individuals in Port Harcourt, Nigeria. Considering the role of TB in driving the HIV pandemic, it is imperative that HIV-positive patients are screened for TB infection regularly to reduce the scale of active HIV-TB co-infection.