Acta Microbiol. Hell., Volume 71, Issue 1 (March 2026) – 8 articles

People living with HIV (PLWH) receiving effective antiretroviral therapy (ART) continue to exhibit chronic immune activation and systemic inflammation despite virological suppression. The viral envelope glycoprotein gp120, which binds the CD4 receptor and mediates viral entry, has been implicated in pro-inflammatory and pro-apoptotic effects in neuronal and endothelial cells. Although gp120 is expressed on the viral surface, its oligomeric structure and its ability to form immune complexes with circulating antibodies may reduce the sensitivity of standard detection assays in serum. Soluble gp120 has been associated with increased levels of pro-inflammatory cytokines, including interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β), as well as chemokines. These mediators may contribute to blood–brain barrier dysfunction, endothelial injury, vascular smooth muscle alterations, and subsequent neurodegenerative and cardiovascular complications. Importantly, gp120 shedding may persist due to viral reservoirs and intermittent reactivation, even during ART. Fostemsavir inhibits the interaction between gp120 and CD4, preventing viral entry and potentially limiting gp120-mediated pathogenic effects. Beyond antiviral activity, this mechanism suggests a potential role in attenuating gp120-mediated inflammation. This review discusses the biological effects of gp120 and the rationale for targeting it therapeutically in PLWH. Full article

Clostridioides difficile infection (CDI) remains a major cause of healthcare-associated morbidity and mortality, particularly among older adults and patients with recent healthcare exposure, underscoring the need for early risk stratification and accurate prognostic assessment. This retrospective observational study evaluated clinical, laboratory, and therapeutic factors associated with disease severity and in-hospital mortality, and assessed the predictive performance of the ATLAS score and the Charlson comorbidity index. A total of 101 adult inpatients with laboratory-confirmed CDI admitted to a Portuguese tertiary care hospital were included. Data were extracted from clinical records and analysed using comparative statistics, multivariable logistic regression, and Kaplan–Meier survival analysis. Advanced age, elevated white blood cell count, renal dysfunction, and prior exposure to multiple antibiotic classes were independently associated with increased disease severity and mortality. The ATLAS score demonstrated good discriminative ability, particularly for short-term mortality, and showed higher sensitivity compared with the Charlson comorbidity index. These findings provide additional evidence on clinical and laboratory factors associated with severe CDI and in-hospital mortality, while supporting the utility of the ATLAS score as a practical tool for early risk stratification in hospitalised patients. Full article

The COVID-19 pandemic necessitated rigorous infection control protocols across hospital environments, particularly in nutrition services. UV-C light emerged as a viable option due to its shortest wavelength, conferring the greatest capacity for nucleic acid (DNA/RNA) penetration in both microorganisms and human cells. We aim to develop and validate an alternative method for decontaminating food carts using UV-C light. A prototype box was created to cover the meal transport carts, with UV-C lamps strategically positioned for irradiation and decontamination. To validate this technology, four different hygiene protocols were compared: Group 1, positive control, with no sanitization procedure; Group 2, cleaned using the standard protocol of the University Hospital of UFS (HU/UFS) with 70% ethanol solution; Group 3, negative control, cleaned using the standard HU/UFS protocol with 70% ethanol and neutral detergent; and Group 4, exposed to UV-C light irradiation for 10 min after food transport. Microbiological samples were collected from 15 distinct points on the carts. Samples were collected using sterile swabs moistened with 0.85% saline solution and incubated in BHI broth at 37 °C for 24 h for presence/absence testing. Positive samples were plated on selective media (CLED, SS, MacConkey and Blood agar), incubated at 37 °C for 24–48 h, and evaluated for colony-forming unit (CFU) count. A statistically significant association was found between the hygiene method and the presence of microbial contamination (p < 0.001), based on both bacterial plate counts and BHI broth growth. Carts sanitized with 70% alcohol showed a lower probability of contamination compared to the control group (alcohol + detergent), while unsanitized carts showed a higher risk. UV-C light treatment resulted in complete absence of bacterial growth. UV-C disinfection demonstrated superior effectiveness in eliminating microorganisms, indicating a promising alternative to traditional methods. Full article

Chlamydia is the most common sexually transmitted infection (STI) worldwide. In 2020, the global prevalence was estimated to be 4.0% among women and 2.5% among men aged 15 to 49 years. In more than 80% of cases, the infection is asymptomatic, thereby increasing the risk of subsequent infections. Complications in women can include chronic pain, pelvic inflammatory disease, and an increased risk of ectopic pregnancies. Chlamydia trachomatis (CT) infections can be diagnosed using several techniques, including cell culture, immunofluorescence, enzyme immunoassays, and polymerase chain reaction (PCR). PCR is regarded as the gold standard for screening and detection of CT. We conducted a three-year retrospective study from January 2022 to December 2024, collecting 4241 cervicovaginal swab samples from outpatient gynecology patients. The overall prevalence of CT in our study was 2.02%. An increase in CT detection during the study period was observed: from 24 cases (1.7%) in 2022 to 30 cases (2%; p = 0.64) in 2023 and 32 cases (2.35%; p = 0.26) in 2024. The highest proportion of cases was observed in the 20–24 and 25–34 age groups. Notably, 7 out of 10 cases were asymptomatic. Risk factors for chlamydial infections include behavioral factors, such as having multiple sexual partners and engaging in risky sexual practices, as well as social and lifestyle influences. Full article

Parvovirus B19 is a DNA virus. Most parvoviruses infect animals; Parvovirus B19 infects humans. Parvovirus B19 is mainly transmitted through respiratory droplets during close contact, but additional routes such as transmission through contaminated blood products and vertical transmission from mother to fetus have also been documented. Infections occur throughout the year, with a seasonal increase between late winter and early summer. Clinical symptoms depend on age, and on patients’ immune status. Healthy, immunocompetent individuals experience asymptomatic or mild infections including a febrile rash; serious complications rarely appear, such as rheumatoid-like arthritis or acute myocarditis. Clusters of myocarditis cases following Parvovirus B19 infections appeared in a daycare in Thessaloniki in 2024. To molecularly and phylogenetically characterize Parvovirus B19 strains detected during a pediatric outbreak associated with elevated troponin levels and myocarditis in Northern Greece, and to compare these strains with isolates from adult cases with mild symptoms in order to explore potential associations between viral genetic variability and cardiac involvement. MinION sequencing protocol was performed for nine whole blood samples, seven belonging to children with myocarditis, and two to adults presenting mild symptoms. Statistical analysis was performed with QualiMap 2.3 and relevant tools. Phylogenetic analysis identified distinct viral groups originating from the samples investigated. A distinct branch was formed by the reference genome and the ones of the adults’ samples, while samples from children with myocarditis provided discrete branches differing from the reference one. The findings demonstrate a clear association between Parvovirus B19 infection and myocarditis in the pediatric cases analyzed. The detected viral strains, including variants identified in several samples, support the role of Parvovirus B19 as a contributing factor in post-infectious cardiac involvement. Although these results reinforce the clinical relevance of Parvovirus B19 in childhood myocarditis, expanding the sample size would allow for a more robust characterization of circulating strains and confirmation of the observed patterns. Full article

Genitourinary infections caused by Candida spp. and other yeasts have increased in incidence, and the emergence of resistant isolates to commonly prescribed antifungals is becoming more frequent. Thus, the purpose of this study was to characterize the physiological characteristics of 38 yeast isolates (Candida albicans [n = 32], Candida tropicalis [n = 3], and Nakaseomyces glabratus [n = 3]) recovered from genitourinary infections to better understand the diversity of their physiological profiles, their virulence factors, and their role in pathogenicity. In addition, an experimental study was conducted to determine the minimum inhibitory concentration (MIC) of the isolates using the M27-A3 microdilution method described by the Clinical Laboratory and Standards Institute. Clinical isolates of Candida spp. studied showed in vitro susceptibility to both fluconazole and clotrimazole, the latter having greater antifungal activity due to its lower MIC₅₀. Statistically significant differences were found between the MICs obtained for fluconazole and clotrimazole, with the latter showing the highest in vitro activity. Therefore, the clinical use of clotrimazole is recommended, as is the ongoing need for this type of analysis to monitor changes in susceptibility profiles over time. Full article

The emergence and dissemination of antimicrobial resistance (AMR) are driven by complex, interconnected mechanisms involving microbial communities, environmental factors, and human activities, with climate change playing a pivotal and accelerating role. Rising temperatures, altered precipitation patterns, and other environmental disruptions caused by climate change create favorable conditions for bacterial growth and enhance the horizontal gene transfer (HGT) of antibiotic resistance genes (ARGs). Thermal stress and environmental pressures induce genetic mutations that promote resistance, while ecosystem disturbances facilitate the stabilization and spread of resistant pathogens. Moreover, climate change exacerbates public and animal health risks by expanding the range of infectious disease vectors and driving population displacement due to extreme weather events, further amplifying the transmission and evolution of resistant microbes. Livestock agriculture represents a critical nexus where excessive antibiotic use, environmental stressors, and climate-related challenges converge, fueling AMR escalation with profound public health and economic consequences. Environmental reservoirs, including soil and water sources, accumulate ARGs from agricultural runoff, wastewater, and pollution, enabling resistance spread. This review aims to demonstrate how the Mediterranean’s strategic position makes it an ideal living laboratory for the development of integrated “One Health” frameworks that address the mechanistic links between climate change and AMR. By highlighting these interconnections, the review underscores the need for a unified approach that incorporates sustainable agricultural practices, climate mitigation and adaptation within healthcare systems, and enhanced surveillance of zoonotic and resistant pathogens—ultimately offering a roadmap for tackling this multifaceted global health crisis. Full article