This article represents part II of a narrative review on HIV and AIDS in Central and Eastern Europe (CEE). After part I, which focused on epidemiology, health policies, testing strategies, and clinical management, this section addresses HIV prevention and the impact of stigma and discrimination on access to HIV care, aims to identify current gaps, and determine key priorities for strengthening HIV prevention efforts and improving HIV care in the region. The review includes prevention approaches, including pre- and post-exposure prophylaxis, treatment as prevention strategy, and harm reduction interventions, and compares their accessibility and implementation across countries. The impact of stigma and discrimination on prevention, diagnosis, and care services was also assessed. The review also includes a section on the successes and gains of several CEE countries in responding to the HIV epidemic.
The aim of the present study was to evaluate the potential of Paenibacillus nuruki AASFL403 extract (PBE) to extend the lifespan of Saccharomyces cerevisiae (Sc). The chronological lifespan assay was performed on three Sc strains with different genetic characteristics. Continuous or acute (30 min) treatment with PBE was performed with concentrations in the range of 0.1–2 mg/mL, depending on the experiment. Continuous treatment of exponentially growing S. cerevisiae 551 with 2 mg/mL PBE resulted in an increased specific growth rate and decreased doubling time. No effect on lifespan was observed for stationary-phase cell suspensions (non-metabolically active cells). The lifespan of Sc Δsod was extended up to day 11, compared to day 7 for the parental strain, when acute treatment (30 min) was performed. Despite its limited impact on yeast lifespan, PBE may act as an adaptogen, activating cellular defense mechanisms. Further research may reveal the exact mechanism of action of PBE.
Lenacapavir, the first approved HIV-1 capsid inhibitor, is now being introduced for both treatment and pre-exposure prophylaxis, yet the capsid-coding region lies outside the pol fragment examined in routine genotypic resistance testing, and baseline data on capsid variability remain scarce, particularly in epidemics dominated by non-B lineages. We applied next-generation sequencing of the HIV-1 gag gene to 103 lenacapavir-naive individuals newly diagnosed in Bulgaria between 2023 and 2025. Nine lineages were identified. Subtype B accounted for 46.6% of the sequences, whereas non-B lineages together predominated (53.4%), led by sub-subtype F1 (13.6%) and CRF01_AE (8.7%); a further 10.7% remained unassigned and grouped predominantly with BF1 recombinant references. The distribution of these lineages differed significantly according to the probable route of transmission (p = 0.007). No major lenacapavir resistance-associated mutation was detected (0 of 103; 95% CI 0.0–3.6). Substitutions at position 107 were the only changes observed at a resistance-associated position: T107S in two individuals and a T107T/S mixture in one (2.9% combined). Notably, the two T107S sequences formed a CRF01_AE pair supported by a bootstrap value of 100, indicating that this accessory polymorphism can persist in closely related viruses. All viruses were genotypically predicted to remain susceptible to lenacapavir. These findings establish a molecular baseline for capsid surveillance in Bulgaria, a South-Eastern European country with a genetically diverse HIV-1 epidemic.
Enteroviruses (EVs) are a common cause of a wide spectrum of infectious diseases, ranging from mild respiratory illnesses to severe neurological conditions, particularly affecting children. Current molecular methods, such as 5'UTR-based PCR for detection and (partial) VP1 gene sequencing for typing, are widely utilized. However, Next-Generation Sequencing (NGS), and bioinformatics offer a comprehensive alternative, enabling full-genome analyses for improved virus characterization, genomic epidemiological surveillance, and outbreak investigation. Despite its advantages, implementation of NGS poses challenges, particularly in standardizing and optimizing laboratory workflows (wet-lab) and bioinformatics analyses (dry-lab), methods that are not often readily accessible in many laboratories. Here, we discuss the potential of NGS as a tool for EV detection/characterization in clinical virology, public health, and research settings. We provide practical options for actions for implementing NGS to advance the understanding and management of enterovirus infections. These recommendations are based on expert discussions during the recent European non-polio enterovirus network (ENPEN) workshop held in Corfu, Greece, on 23-24 May 2024, aiming to guide harmonization of NGS practices across clinical, public health, and research settings.
Background: Bats are important reservoir hosts for numerous emerging pathogens with zoonotic potential. In Europe, 47 bat species have been recorded, 33 of which occur in Bulgaria. Previous research has shown that bats harbor several dangerous viruses, including SARS, Ebola, Nipah, Hendra, Marburg, and MERS, as well as various bacterial, fungal, and protozoan pathogens. Despite these findings, information about the composition of the bat blood microbiome remains limited. The present study aimed to characterize the microbial diversity present in the blood of bats inhabiting caves in Bulgaria. Materials and Methods: Blood samples were collected from bat species belonging to the families Vespertilionidae and Rhinolophidae inhabiting three caves in Bulgaria. Between 10 and 30 µL of blood was obtained from each individual. Samples from 122 bats were combined into 14 pooled samples. Additionally, heart tissue and two spleens were collected. DNA extraction was performed, followed by metagenomic sequencing using Illumina shotgun technology with a sequencing depth of 6 Gb. Taxonomic classification of quality-filtered reads was conducted using the Kraken2 tool with the RefSeq NCBI bacterial database within the Galaxy platform (www.usegalaxy.eu). Operational taxonomic unit (OTU) tables were generated using Bracken and visualized with Pavian software. Results: Metagenomic analysis revealed the presence of numerous microbial taxa in bat blood samples. A notable abundance of potentially pathogenic bacteria was detected, with sequencing reads exceeding 10000 for species belonging to the genera Mycobacterium, Mycoplasma, and Bartonella. Conclusions: The results indicate that bats in Bulgaria may serve as hidden or potential reservoirs of bacterial pathogens with zoonotic relevance. These findings highlight the importance of continued surveillance of bat-associated microbiota to better understand potential public health risks.
