ABSTRACT
Surveillance of emerging viral variants is critical to ensuring that blood screening and diagnostic tests detect all infections regardless of strain or geographic location. In this study, we conducted serological and molecular surveillance to monitor the prevalence and diversity of HIV, HBV, and HTLV in South Cameroon. The prevalence of HIV was 8.53%, HBV was 10.45%, and HTLV was 1.04% amongst study participants. Molecular characterization of 555 HIV-1 specimens identified incredible diversity, including 7 subtypes, 12 CRFs, 6 unclassified, 24 Group O and 2 Group N infections. Amongst 401 HBV sequences were found a rare HBV AE recombinant and two emerging sub-genotype A strains. In addition to HTLV-1 and HTLV-2 strains, sequencing confirmed the fifth known HTLV-3 infection to date. Continued HIV/HBV/HTLV surveillance and vigilance for newly emerging strains in South Cameroon will be essential to ensure diagnostic tests and research stay a step ahead of these rapidly evolving viruses.
Subject(s)
HIV Infections/epidemiology , HIV-1/classification , HTLV-I Infections/epidemiology , Hepatitis B virus/genetics , Hepatitis B, Chronic/epidemiology , Human T-lymphotropic virus 1/genetics , Human T-lymphotropic virus 2/genetics , Human T-lymphotropic virus 3/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Viral/blood , Antigens, Viral/blood , Base Sequence , Cameroon/epidemiology , Child , Child, Preschool , DNA, Viral/genetics , Female , Genome, Viral/genetics , HIV Infections/virology , HIV-1/genetics , HTLV-I Infections/virology , Hepatitis B virus/classification , Hepatitis B virus/isolation & purification , Hepatitis B, Chronic/virology , Human T-lymphotropic virus 1/classification , Human T-lymphotropic virus 1/isolation & purification , Human T-lymphotropic virus 2/classification , Human T-lymphotropic virus 2/isolation & purification , Human T-lymphotropic virus 3/classification , Human T-lymphotropic virus 3/isolation & purification , Humans , Infant , Male , Middle Aged , Sequence Analysis, DNA , Young AdultABSTRACT
Human immunodeficiency virus type 1 (HIV-1) genetic diversity presents a challenge to nucleic acid-based assays with regard to sensitivity of detection and accuracy of quantification. The Abbott LCx HIV RNA Quantitative assay (LCx(R) HIV assay), a competitive RT-PCR targeting the pol integrase region, was evaluated using a panel of 297 HIV-1 seropositive plasma samples from Cameroon, Uganda, Brazil, Thailand, Spain, Argentina and South Africa. The panel included group M subtypes A-G, mosaics, and group O based on sequence analysis of gag p24, pol integrase, and env gp41. The LCx HIV assay quantified 290 (97.6%) of the samples, including all the group O samples tested. In comparison, the Roche AMPLICOR HIV-1 MONITOR test versions 1.0 and 1.5 quantified 67.3 and 94.6% of the samples, respectively. No group O specimens were quantified by either version of AMPLICOR HIV-1 MONITOR. Seven specimens were below the detectable limits of all the three assays. The LCx HIV assay had fewer nucleotide mismatches at primer/probe binding sites as compared with both AMPLICOR HIV-1 MONITOR tests. The high degree of nucleotide conservation within the pol target region enables the LCx HIV assay to efficiently quantify the HIV-1 subtypes A-G and the most genetically diverse HIV-1, group O.
