Search Results (167)

Background/Objectives: Listeria monocytogenes is a foodborne pathogen of major public health concern due to its ability to invade host cells and cause severe illness. This study aimed to develop and validate a multi-tiered screening pipeline to identify Bacillus strains with probiotic potential against L. monocytogenes. Methods: A total of 26 Bacillus isolates were screened for antimicrobial activity, gastrointestinal resilience, and host cell adhesion. A fluorescence-based infection assay using mCherry-expressing HCT 116 cells was used to assess cytoprotection against L. monocytogenes NCTC 7973. Eight strains significantly improved host cell viability and were validated by quantification of intracellular CFU. Two top candidates were tested in a murine model of listeriosis. The genome of the lead strain was sequenced to evaluate safety and biosynthetic potential. Results: B. subtilis CECT 8266 completely inhibited intracellular replication of L. monocytogenes in HCT 116 cells, reducing bacterial recovery to undetectable levels. In vivo, it decreased splenic bacterial burden by approximately 6-fold. Genomic analysis revealed eight bacteriocin biosynthetic clusters and silent antibiotic resistance genes within predicted genomic islands, as determined by CARD and Alien Hunter analysis. The strain also demonstrated bile and acid tolerance, as well as strong adhesion to epithelial cells. Conclusions: The proposed pipeline enables efficient identification of probiotic Bacillus strains with intracellular protective activity. B. subtilis CECT 8266 is a promising candidate for translational applications in food safety or health due to its efficacy, resilience, and safety profile. Full article

Background/Objectives: Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, remains a major neglected tropical disease, with over six million cases concentrated, primarily in Latin America. Despite decades of research, treatment continues to rely on two outdated drugs—benznidazole and nifurtimox—both of which exhibit limited efficacy and are associated with severe side effects. In this context, drug repurposing presents a promising strategy to accelerate the development of safer and more effective therapies. Nitroxoline, a hydroxyquinoline compound widely used in Europe to treat bacterial urinary tract infections, has recently garnered attention for its broad-spectrum antimicrobial and anticancer activities. This study evaluated the antitrypanosomal potential of nitroxoline against both epimastigote and intracellular amastigote forms of T. cruzi, demonstrating significantly greater efficacy than benznidazole. Methods: In addition to its antiparasitic activity, we investigated the mechanism of parasite death and found that nitroxoline induces hallmarks of programmed cell death, including chromatin condensation, mitochondrial membrane depolarization, ATP depletion, reactive oxygen species accumulation, and increased membrane permeability. These cellular events are critical for minimizing host tissue inflammation and suggest a safer therapeutic profile. Results: The nitroxoline was shown to induce greater activity than the reference treatment, benznidazole, in addition to triggering events related to apoptotic or silent cell death. Conclusions: Given its established clinical use and favorable safety data, nitroxoline emerges as a strong candidate for further investigation as a repurposed treatment for Chagas disease. Future work should focus on in vivo efficacy, pharmacokinetics, and drug delivery strategies to enhance systemic bioavailability. Full article

Zika and malaria are important vector-borne febrile illnesses in humans. In this study, we determined the circulation of Zika virus and malaria infections, their hotspots, and their predominant clinical features. A cross-sectional study was carried out in six Local Government Areas (LGAs) in Kaduna State, Nigeria, from September 2018 to May 2019. Four hundred and twenty sera were screened for Zika virus (ZV) IgM and IgG, and Plasmodium falciparum antigen using ELISA and immunochromatographic test, respectively. Overall, a seroprevalence of 14.5% was found for Zika, and 9.3% for malaria. Nineteen (4.5%) and thirty-five (8.3%) patients were seropositive for ZV IgM and IgG, respectively. Co-infection rates for Zika (ZV IgM) and malaria (0.5%: 2/420), and for ZV IgG and malaria (0.7%: 3/420) were observed. Lere (10%: 7/70 for ZV IgM), Kachia (14.3%: 10/70 for ZV IgG) and Zaria (18.6%: 13/70 for malaria) LGAs were identified as hotspots for Zika and malaria. Age was significantly associated with malaria (p = 0.008) and ZV IgG (p = 0.004). Patients aged 1–10 years had the highest malaria seroprevalence (18.4%), while those aged 21–30 years had the highest ZV IgM prevalence (6.1%: 7/114). Out of the pregnant patients (56/420) tested, 5.37% (3/56) had antibodies to both recent and past ZV infection. A significant association was found between maculopapular rash (p = 0.021) and Zika, as well as between duration of the fever and recent Zika infection (p = 0.041). We highlight that malaria is endemic in Kaduna and that ZV is silently circulating, providing baseline data for further molecular epidemiological studies. Full article

Bovine leukemia virus (BLV) is classified as a Deltaretrovirus and shows close genomic and biological similarities with human T-cell leukemia viruses (HTLVs). It serves as the etiological agent for enzootic bovine leukosis (EBL), which stands as the most prevalent neoplastic disease affecting cattle globally. Additionally, BLV has been identified as a potential zoonotic pathogen, although the risk to human health remains a subject of ongoing research. The insidious nature of BLV lies in its predominantly subclinical presentation; the majority of BLV-infected cattle show no apparent symptoms. This subclinical nature poses challenges for disease detection and control, as infected animals can remain unnoticed carriers, contributing to the silent spread of the virus within herds. This characteristic also underscores the importance of surveillance and early detection strategies to monitor BLV prevalence and mitigate its spread. Despite concerted efforts in some regions to implement eradication programs, BLV continues to maintain a high prevalence worldwide. The persistence of BLV in cattle populations highlights the need for innovative and integrated approaches to control and manage the disease effectively. The development of a BLV vaccine represents a significant breakthrough in the fight against BLV transmission. A successful vaccine can not only reduce the incidence of BLV infection but also minimize the associated economic losses linked to reduced milk production, reproductive issues, and the premature culling of infected animals. Therefore, a comprehensive understanding of BLV, encompassing its origin, evolutionary patterns, epidemiology, risk factors, and control strategies, is pivotal. Such knowledge serves as the foundation for the development of effective vaccines, diagnostic tools, and control measures. Through this review, we aim to consolidate and present this multifaceted understanding of BLV, providing valuable insights and guidance for researchers, veterinarians, and policymakers involved in BLV prevention and control efforts globally. Full article

The present study reports on the management of an EHV-1 outbreak at a large, multi-week equestrian event with ongoing showing. Within a 48 h period, 8 horses out of a cohort of 38 horses from the same trainer displayed elevated rectal temperatures ranging from 38.4 to 39.0 °C. Initial testing using a point-of-care PCR assay detected EHV-1 in 2/8 horses, with the results being confirmed at a later time by qPCR. As a precautionary measure and because of the inability to isolate the entire at-risk population, the 38 horses were relocated to an equine facility outside the equestrian event for daily monitoring and weekly EHV-1 qPCR testing of nasal secretions. Overall, 22/38 (58%) horses tested EHV-1 qPCR-positive in nasal secretions over the monitoring period of 28 days, with only one additional horse developing fever. Once all 38 horses tested EHV-1 qPCR-negative twice, 7 days apart, 17 horses returned to the equestrian event to compete for the remaining 2 weeks of the circuit. The present study highlights the importance of isolating and testing horses with fever but also subfebrile horses, as EHV-1 can cause silent infection. The relocation of the exposed horses to an outside facility allowed close monitoring of these horses while reducing the risk of direct and indirect exposure to other show horses. The regular testing for EHV-1 through nasal secretions during the outbreak, coupled with proper biosecurity protocols, allowed the safe return of the show horses to the event. The key elements in reducing the spread of EHV-1 were the routine assessment of rectal temperature, early isolation of horses with elevated rectal temperature and on-site EHV-1 PCR testing. Full article

Outbreaks involving carbapenemase-producing enterobacteria (CPE) have become a common occurrence in healthcare settings. While clonal dissemination is firmly established as a cause for these outbreaks, horizontal gene transfers (HGTs) between different species of Enterobacterales found in clinical and environmental isolates are less so. To gather evidence backing up this hypothesis, a review covering the 2013–2024 period was performed. HGTs between different species of clinical and environmental Enterobacterales were identified in thirteen papers, half of those published within the last three years. A combination of short- and long-read whole genome sequencing (WGS) was predominantly used to identify mobile genetic elements and plasmids. The more frequently reported carbapenemases were KPCs, followed by NDMs and IMPs. Predictably, broad-host-range plasmids were responsible for over 50% of HGTs, with the IncA/C group being in the lead. Klebsiella pneumoniae and Enterobacter cloacae complexes were the most frequent species identified in clinical samples, while Citrobacter freundii dominated environmental ones. Drains and pipework frequently constituted CPE reservoirs in protracted outbreaks, alternating epidemic outbursts with silent phases. Including WGS in a systematic environmental surveillance would help in swiftly identifying those CPE reservoirs and possibly help better control plasmid outbursts by allowing the implementation of adequate infection prevention and control measures. Full article

The demand for unconventional pets has markedly increased in recent years worldwide. Among them, many species of mammals are frequently kept in domestic environments in close contact with their owners. Pets often harbor zoonotic microorganisms without showing clinical signs; therefore, owners do not suspect that they can be a source of pathogens. Pets of several unconventional species may act mainly as maintenance hosts for leptospires; they are clinically silent but shed the spirochetes in their urine representing a serious risk of infection for people living in the same domestic area. However, their role as maintenance or incidental hosts seems variable in relation to the animal species, and it has not always been elucidated. No vaccines against Leptospira spp. are available for unconventional mammal pets, and so prophylaxis is based on rigorous hygienic measures and the identification of infected animals through indirect and/or direct diagnosis for leptospirosis. Full article

Background/Objective In every surgical environment, the prevention of surgical site infections is not merely desirable but essential, given their profound impact on patient health and healthcare costs. To optimize patient care during surgery, a thorough exploration and assessment of all intraoperative nursing practices are necessary, guided by empirical evidence. The aim of this study was to explore nurses’ experiences with surgical site infection prevention practices in the intraoperative setting. Methods Twenty-one nurses working in clinical settings in Hong Kong participated in semi-structured interviews for this qualitative study. Data were analyzed using Colaizzi’s seven-step method. Results Four main themes were identified from the interview data: ensuring safety and minimizing threats; facing silent, intangible, and hidden risks; team collaboration in eliminating risks; and persistent knowledge acquisition. Conclusions Nurses encountered diverse obstacles tied to teamwork, updated knowledge, communication, and patient safety. Enhanced quality of care in clinical settings can be achieved through strategic implementations. Focusing on quality improvement initiatives, establishing consistent teams, and recognizing the vital role of nurses strengthen care delivery. These actions contribute significantly to preventing surgical site infections and ensuring patient safety during intraoperative nursing practices. Full article

Anaplasma phagocytophilum, a tick-borne Rickettsiales, causes an emerging disease among humans and animals called granulocytic anaplasmosis. The organism expresses an immunodominant surface protein, MSP2/P44, that undergoes rapid antigenic variation during single infections due to gene conversion at a single genomic expression site with sequences from one of ~100 transcriptionally silent genes known as “functional pseudogenes”. Most studies have indicated that the predominant gene conversion mechanism is the insertion of complete central variable regions (CVRs) into the msp2/p44 expression site via homologous recombination through 5′ and 3′ conserved regions. This suggests that it is possible that persistent infections by one strain may be self-limiting due to the exhaustion of the antigenic repertoire. However, if there is substantial recombination within the functional pseudogene repertoires themselves, it is likely that these repertoires have a high rate of change. This was investigated here by analyzing the repertoires of msp2/p44 functional pseudogenes in genome-sequenced A. phagocytophilum from widely different geographic locations in the USA and Europe. The data strongly support the probability of recombination events having occurred within and between msp2/p44 repertoires that is not limited to the 5′ and 3′ conserved regions of the CVR, greatly expanding the total potential variation. Continual variation of msp2/p44 repertoires is predicted to aid the organism in overcoming existing immunity in the individual and causing superinfections among immune populations, and this may facilitate the adaptation of the microorganism to infect and cause disease in different species. Full article

Neglected Tropical Diseases are a group of 25 conditions caused by diverse agents. They mostly affect people with poorer health outcomes, particularly preventable diseases. The social determinants of health influence the development and progression of these poverty diseases, with inadequate sanitation presenting chronicity, high morbidity, and economic impacts. Chagas disease, a prominent Neglected Tropical Disease caused by the intracellular pathogen Trypanosoma cruzi, is endemic in Latin America but is increasing as a global concern due to population migration. It is transmitted through insect vectors, congenitally, orally via contaminated food and beverage, via transfusions and organ donation, and due to laboratory accidents, among other minor relevant routes. As a silent illness, with many infected individuals remaining asymptomatic, it contributes to underdiagnosis, and delayed treatment that involves nitro derivatives is often discontinued due to side effects. Chagas disease spreads in non-endemic areas like the United States of America and Europe. Blood screening practices vary, with endemic regions implementing universal testing, while non-endemic areas rely on selective methods. Recent innovations, such as riboflavin–ultraviolet light treatment and arylimidamide compounds, represent promising alternatives to reduce transfusion transmission. This review presents an analysis of Trypanosoma cruzi transmission through blood and derivatives, addressing the main routes, globally implemented control strategies, and recent advancements in blood bank safety. Full article

This study aimed to determine the prevalence of co-infection with malaria and intestinal parasites and assess its association with anemia in school-aged children from rural and urban settlements in Gabon. This cross-sectional study involved afebrile school children recruited at schools between May and June 2021. Blood and stool samples were collected from participants whose parents or legal guardians provided informed consent to participate in the study. Hemoglobin concentration (Hb) was measured using a HemoCue photometer (HemoCue 201, HemoCue, Angelholm, Sweden). Giemsa-stained blood films were examined to detect malaria parasites and any filarial infections, while the merthiolate-iodine concentration (MIC) method was used to identify intestinal parasitic infections (IPI). A total of four hundred and seventy (470) school-aged children were successfully enrolled in this study. The observed prevalence values were as follows: malaria infection at 69.6%, IPIs at 19.1%, filaria at 5.1%, Schistosoma infection at 15.0%, and anemia at 29.0%. Co-infections of malaria with IPIs, filaria, and Schistosoma were present in 12.3%, 4.7%, and 6.6% of the children, respectively. Malaria and filaria infections were associated with residing in Lastourville city (p < 0.05) and were also correlated with age (p < 0.05), whereas IPIs were associated with male gender and living in the city of Lastourville. Anemia was linked to malaria infection (p < 0.05) and was more prevalent among children living in rural areas. The findings of this study indicate that malaria, IPIs, and Schistosoma infections continue to pose a significant public health problem in the study area, even though only malaria infection appeared to be associated with anemia. Nevertheless, these results highlight the need for implementing control measures to reduce the prevalence of malaria, IPIs, filaria, and Schistosoma, particularly in Lastourville. Full article

Adenovirus (AdV) infection has been rarely documented in cats and other felids. Partial sequences of the hexon and fiber genes of a Hungarian feline adenovirus isolate (FeAdV isolate) showed a close relationship to human AdV (HAdV) type C1. Further molecular and biological characterization is reported here. Whole-genome sequencing revealed two silent mutations in the genome of the FeAdV isolate compared to a HAdV-C1 reference strain (at positions 14,096 and 15,082). Competitive antibody binding to the Coxsackie–adenovirus receptor and α_vβ₃ and α_vβ₅ integrin coreceptors inhibited the binding of the FeAdV isolate in different cell lines, but residual infections suggested alternative entry routes. The FeAdV isolate was found to be more sensitive to heat, low pH and detergents, but more resistant to alkaline and free chlorine treatments, as well as to ribavirin, stavudine and cidofovir treatments, than other human AdV types. We observed a suppression of IL-10 and TGF-β1 production during the entire course of viral replication. This immunomodulation may restore intratumoral immunity; thus, the FeAdV isolate could serve as an alternative oncolytic vector. Collectively, our results support that the Hungarian FeAdV isolate is a variant of common HAdV-C1. The cohabitation of cats with humans might result in reverse zoonotic infection. Felids appear to be susceptible to persistent and productive adenovirus infection, but further studies are needed to better understand the clinical and epidemiological implications. Full article

Antimicrobial resistance is becoming a critical issue due to the widespread and indiscriminate use of antibiotics and antifungals to treat common infections, leading to a growing shortage of effective drugs. Moreover, the increase in antimicrobial resistance is enhancing the pathogenicity and virulence of various pathogens. Microorganisms are key sources of chemically diverse specialized metabolites, which are produced in the final stages of their growth cycle. These metabolites hold significant value in chemical, pharmaceutical, and agrochemical industries. One of the major challenges researchers face in this field is the frequent isolation of already-known substances when classical protocols are used. To address this, several innovative strategies have been developed. The co-culture approach is a powerful tool for activating silent biosynthetic gene clusters, as it simulates natural microbial environments by creating artificial microbial communities. This method has shown promising results, with new compounds being isolated and the yields of target substances being improved. In this context, this review provides examples of antimicrobial compounds obtained from co-cultures of endophytic fungi, conducted in both liquid and solid media. Additionally, the review discusses the advantages and challenges of the co-culture technique. Significance and Impact of the Study: Microbial co-culture is a valuable strategy for discovering new natural products with antimicrobial activity, as well as for scaling up the production of target substances. This review aims to summarize important examples of endophyte co-cultures and highlights the potential of endophytic fungi co-culture for pharmacological applications. Full article

Wisteria vein mosaic virus (WVMV, Potyvirus wisteriae), a virus belonging to the genus Potyvirus, is responsible for Wisteria vein mosaic disease (WMD), a severe disease that affects Wisteria, a genus of garden plants acclaimed worldwide. Although probably originating in the Far East, WVMV infection was first reported in the US, and subsequently in numerous countries. Following the first molecular detection of an Italian isolate, WVMV Bari, its full-length genome was achieved using NGS barcoding technology. A PhyML phylogenetic analysis, supported by clustering algorithm validation, identified a clear separation between two phylogroups. One major clade comprised WVMV strains isolated from Wisteria spp. A second clade grouped three highly divergent strains, at the borderline species threshold, all found in non-wisteria hosts. Relying on a Relative Time Dated Tips (RTDT) molecular clock, the first emergence of WVMV clades has been traced back to around the 17th century. A network inference analysis confirmed the sharp separation between the two host-related phylogroups, also highlighting the presence of potential intermediate variants. Inter-population genetic parameters revealed a very high genetic differentiation in both populations, which was made reliable by statistically significant permutation tests. The migrant number (Nm) and fixation index (F_ST) evidenced a restricted gene flow and strong population structures. According to the dN/dS ratio and negative neutrality tests, it was derived that purifying selection at the expense of non-silent variants is underway within WVMV populations. Targeting WVMV evolutionary traits, the present effort raised interesting questions about the underestimated potential of this culpably neglected species to spread in economically relevant crops. The main intention of our study is, therefore, to propose an evolution-based analysis approach that serves as a case study to investigate how other potyviruses or newly emerging viruses may spread. Full article

Malignant nasopharyngeal tumors account for approximately 4% of ENT malignant tumor pathology and 1% of all cancers. The diagnosis of nasopharyngeal tumors is often late, the reason being the location in a silent anatomical region in terms of symptomatology and accessibility. Thus, approximately 70% of newly diagnosed patients with nasopharyngeal carcinoma unfortunately present with the condition in an advanced local stage. The early signs and symptoms are varied (nasal obstruction, hearing loss, otalgia, headache) and are usually ignored by the patient and even by the doctor in the initial stage of nasopharyngeal tumor evolution. Approximately 5% of patients have systemic metastases at presentation, the most common location being bone. Latent Epstein-Barr virus infection appears to be involved in the pathogenesis of nasopharyngeal carcinoma. There is no exact evidence of how often a nasopharynx tumor’s first sign is unilateral hearing loss. Thus, further work is required to determine that exactly to help patients get diagnosed faster and therefore improving their therapeutical options. This study aims to explore which symptoms are most common as the first indication of NPC, as well as how these symptoms compare to each other in terms of frequency and likelihood of occurrence. Full article