Viruses

Background: Prion diseases represent a group of rare, progressive, and invariably fatal neurodegenerative disorders. Their hallmark is the infectious nature of the misfolded prion protein (PrP^Sc), which propagates by inducing conformational changes in the physiological form (PrP^C). Despite advances in basic science, these disorders still pose major clinical and therapeutic challenges. Methods: A narrative review of the scientific literature was conducted across major biomedical databases, including PubMed, Scopus, Web of Science, and Google Scholar, covering publications up to January 2025. In addition, we describe an illustrative clinical case of a young patient with probable iatrogenic Creutzfeldt–Jakob disease following corneal transplantation, used to highlight diagnostic uncertainty and infection-control implications. Findings: Evidence confirms that PrP^Sc drives neurodegenerative processes and transmissibility, with phenotypic and genetic variants influencing clinical course and prognosis. From a diagnostic perspective, neuroimaging techniques and cerebrospinal fluid biomarkers have undergone substantial refinement, with RT-QuIC emerging as a highly specific and sensitive assay. Therapeutic options remain unsatisfactory: no treatment has shown a significant impact on survival. However, innovative strategies (including monoclonal antibodies, gene-based interventions, and modulation of PrP^C) represent promising avenues of investigation. Conclusions: Prion diseases remain an unresolved challenge at the intersection of neurology and infectious diseases. Earlier diagnosis through advanced biomarkers and continued development of targeted therapies are essential to improve patient management, while the persistence of iatrogenic cases underscores the ongoing relevance of surveillance and preventive strategies in clinical practice.

Bacteriophages are promising antibacterial agents for managing acne vulgaris caused by Cutibacterium acnes, particularly given increasing antibiotic resistance. Here, we isolated and characterized two lytic Cutibacterium phages, NS-ph1 and NS-ph2, from acne lesions. Both bacteriophages exhibited a broad lytic spectrum, with a high activity against 27 C. acnes strains. Adsorption assays indicated rapid attachment and one-step growth experiments revealed latent periods of 4 h (NS-ph1) and 2 h (NS-ph2) and burst sizes of 70 and 59 PFU per infected cell, respectively. After long-term storage at room temperature, both phages retained infectivity for 3 months. Genome sequencing revealed linear dsDNA genomes of 29,490 bp (NS-ph1) and 29,189 bp (NS-ph2) with 51 and 46 predicted ORFs, respectively, and no tRNAs. No genes associated with lysogeny, toxins, or antibiotic resistance were detected. Comparative genomics placed both phages within the genus Pahexavirus. Together, these data expand the diversity of Pahexavirus and provide two well-characterized lytic candidates for further evaluation in anti-acne phage therapy.

Background: In 2022, Romania experienced a sharp increase in hepatitis A virus (HAV) infections, with evidence of predominant fecal–oral transmission through sexual contact, raising concern for an outbreak among men who have sex with men (MSM). Methods: We conducted a prospective multicenter study between 1 March 2022 and 1 March 2023 in two tertiary hospitals in Bucharest. HAV infection was defined by a compatible clinical presentation, elevated liver enzymes, and positive anti-HAV IgM serology. Clinical and laboratory characteristics were compared by transmission route and HIV status. Results: A total of 191 patients were diagnosed with HAV, including 105 MSM and 86 with foodborne transmission. All were unvaccinated. Most patients were male (82.2%), with a median age of 30 years (IQR 24–38). MSM were significantly younger and reported higher-risk sexual behaviors, including chemsex and multiple or occasional partners (p < 0.0001). Among MSM, 48 (25.1%) were living with HIV, most with preserved immune status and undetectable viral loads. Clinical manifestations were similar across groups, with jaundice being most frequent (89.5%). However, MSM exhibited more severe hepatocellular injury, reflected by higher ASAT and ALAT levels and lower prothrombin concentration, independent of HIV status. MSM were also more likely to have concomitant sexually transmitted infections, including syphilis and mpox (p < 0.001). Disease was predominantly mild, although MSM had longer hospital stays. Conclusions: The 2022 HAV surge in Romania was driven by both sexual and foodborne transmission. Targeted HAV vaccination, along with integrated sexual health services and harm-reduction strategies, is essential to prevent future outbreaks.