Current ARTs, Virologic Failure, and Implications for AIDS Management: A Systematic Review

Antiretroviral therapies (ARTs) have revolutionized the management of human immunodeficiency virus (HIV) infection, significantly improved patient outcomes, and reduced the mortality rate and incidence of acquired immunodeficiency syndrome (AIDS). However, despite the remarkable efficacy of ART, virologic failure remains a challenge in the long-term management of HIV-infected individuals. Virologic failure refers to the persistent detectable viral load in patients receiving ART, indicating an incomplete suppression of HIV replication. It can occur due to various factors, including poor medication adherence, drug resistance, suboptimal drug concentrations, drug interactions, and viral factors such as the emergence of drug-resistant strains. In recent years, extensive efforts have been made to understand and address virologic failure in order to optimize treatment outcomes. Strategies to prevent and manage virologic failure include improving treatment adherence through patient education, counselling, and supportive interventions. In addition, the regular monitoring of viral load and resistance testing enables the early detection of treatment failure and facilitates timely adjustments in ART regimens. Thus, the development of novel antiretroviral agents with improved potency, tolerability, and resistance profiles offers new options for patients experiencing virologic failure. However, new treatment options would also face virologic failure if not managed appropriately. A solution to virologic failure requires a comprehensive approach that combines individualized patient care, robust monitoring, and access to a range of antiretroviral drugs.

Complete Genomic Analysis of VRE From a Cattle Feedlot: Focus on 2 Antibiotic Resistance

Practices in intensive animal farming such as the extensive use of antimicrobials have significant impacts on the genetic make-up of bacterial communities, especially on that of human/animal commensals. In this report, whole genome sequencing of two vancomycin-resistant enterococci (VRE) isolates from a cattle feedlot in the North West Province, South Africa, was used to highlight the threats that extensive antimicrobial usage in intensive animal rearing represents for environmental microbiomes and the food chain. The genomic DNA of the studied strains was extracted using a DNA extraction kit. Whole-genome sequencing was performed through next-generation sequencing. The genomes of Enterococcus durans strain NWUTAL1 and Enterococcus gallinarum strain S52016 consisted of 3,279,618 and 2,374,946 bp, respectively with G + C contents of 40.76 and 43.13%, respectively. Antibiotic resistance genes (ARG), plasmids and virulence factors (involved in biofilm formation, colonization and copper/silver efflux system), were detected in the genomes of both strains. The presence of these genetic determinants in the studied strains is a cause for concern as they may disseminate and find their way into the food chain via horizontal gene transfer amongst bacteria of the different ecological niches. Issues of this nature cannot be undermined and are relevant as far as food safety is concerned.

Virulence profiles of vancomycin-resistant enterococci isolated from surface and ground water utilized by humans in the North West Province, South Africa: a public health perspective

Vancomycin-resistant enterococci (VRE) have been responsible for numerous outbreaks of serious infections in humans worldwide. Enterococcus faecium and Enterococcus faecalis are the principal species that are frequently associated with vancomycin resistance determinants, thus usually implicated in hospital- and community-acquired infections in humans. The study aim was to determine the antibiotic resistance and virulence profiles of VREs isolated from surface and groundwater samples that are used by humans in the North West Province, South Africa. A total of 170 water samples were collected and analyzed. Eighty-one potential isolates were screened for characteristics of Enterococcus species using preliminary biochemical tests, PCR assays and sequence analysis. The antimicrobial resistance profiles of the isolates against nine antibiotics were determined and a dendrogram was generated to access the relatedness of the isolates. The isolates were screened for the presence of antibiotic resistance and virulence genes by multiplex PCR analysis. A total of 56 isolates were confirmed as Enterococcus species and the proportion of E. faecium (46.9%) was higher than E. faecalis (29%) and E. saccharolyticus (1.2%). Sequence data of E. faecium, E. faecalis, and E. saccharolyticus isolates revealed 97 to 98% similarities to clinical strains deposited in NCBI Genbank. Large proportions (44; 78.6%) of the isolates were resistant to vancomycin while 16 and 3.6% of the isolates possessed the vanA and vanB genes respectively. The MAR phenotype Vancomycin-Nalidixic Acid-Streptomycin-Chloramphenicol-Ampicillin-Oxytetracycline-Gentamycin-Nitrofurantoin-Sulphamethoxazole indicated that some isolates were resistant to all of the nine antibiotics tested. Cluster analysis of antibiotic resistance data revealed two major clusters. Sixteen (36.4%), 14 (27.3%), 3 (6.8%), and 2 (4.5%) of the VRE isolates possessed the gel, asa1, hyl, and esp virulence genes respectively while the cylA gene was not detected in the study. Multiple antibiotic-resistant enterococci were also resistant to vancomycin and possessed virulence determinants indicating that they can pose severe public health complications on individuals who consume contaminated water.