Pathogens

14 pages, 2330 KiB

Open AccessArticle

Antimicrobial Resistance and Risk Factors of Canine Bacterial Skin Infections

by Qian Wang, Siyu Chen, Shizhen Ma, Ying Jiao, Huiyi Hong, Siying Wang, Wei Huang, Qi An, Yu Song, Xukun Dang, Gege Zhang, Haiqin Ding, Yang Wang, Zhaofei Xia, Lu Wang and Yanli Lyu

Pathogens 2025, 14(4), 309; https://doi.org/10.3390/pathogens14040309 - 24 Mar 2025

Abstract

Bacterial skin infections are common in dogs and often secondary to underlying conditions like allergies or ectoparasite infestations. Untreated primary causes can lead to recurrent infections and an increased risk of antimicrobial resistance, including methicillin-resistant Staphylococcus pseudintermedius (MRSP), posing a substantial clinical challenge. [...] Read more.

Bacterial skin infections are common in dogs and often secondary to underlying conditions like allergies or ectoparasite infestations. Untreated primary causes can lead to recurrent infections and an increased risk of antimicrobial resistance, including methicillin-resistant Staphylococcus pseudintermedius (MRSP), posing a substantial clinical challenge. Here, we analyzed 896 canine bacterial skin infection samples collected from the China Agricultural University Veterinary Teaching Hospital between 2018 and 2022. Species identification was confirmed by MALDI-TOF and 16S rRNA gene sequencing. Of the 896 samples, 722 (80.6%) yielded 1123 bacterial isolates, with Staphylococcus pseudintermedius (n = 421), Pseudomonas aeruginosa (n = 108), and Escherichia coli (n = 73) being the most prevalent. Antimicrobial susceptibility was evaluated using the broth microdilution method according to CLSI guidelines. Notably, resistance to florfenicol in S. pseudintermedius increased from 9.1% in 2018 to 20.0% in 2022, while resistance to ceftriaxone in E. coli rose from 30.0% to 72.7% over the same period. Among 305 reviewed cases, pyoderma (47.5%, 145/305) was the most common infection type, predominantly associated with S. pseudintermedius (n = 114), followed by otitis (25.6%, 78/305) primarily linked to P. aeruginosa (n = 24). Mixed infections occurred in 35.4% (108/305) of cases, with S. pseudintermedius as the most frequently isolated species in both single and mixed infections. The multivariable logistic regression model revealed that MRSP infections were correlated with a history of invasion (p <0.001) and prolonged disease duration (six months to less than one year: p = 0.005; one year or longer: p < 0.001). Core-genome SNP analysis showed that eight dogs were infected with identical S. pseudintermedius strains, in which one dog exhibited a shift from gentamicin susceptibility to resistance within nine days. Conversely, three dogs were infected by distinct S. pseudintermedius strains at two time points. To effectively manage MRSP infections and chronic skin infections in dogs, rigorous disinfection protocols in veterinary hospitals, control of disease duration, prevention of recurrent infections, and continuous monitoring of antibiotic resistance patterns are essential. Full article

(This article belongs to the Section Bacterial Pathogens)

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15 pages, 1913 KiB

Open AccessArticle

Synergistic Inhibition of Candida albicans by Cranberry Proanthocyanidins and Probiotics: Novel Strategies for Vulvovaginal Candidiasis Treatment

by Yu-Ru Wu, Jung-Sheng Chen, Lei-Chin Chen, Laura Chen, Yu-Fen Huang and Chien-Sen Liao

Pathogens 2025, 14(4), 308; https://doi.org/10.3390/pathogens14040308 - 24 Mar 2025

Abstract

Vulvovaginal candidiasis (VVC) is a common gynecological condition primarily caused by Candida albicans. The excessive use of antifungal drugs has led to increased drug resistance, necessitating the search for alternative therapies. This study investigates the synergistic antifungal effects of cranberry proanthocyanidins (PACs) [...] Read more.

Vulvovaginal candidiasis (VVC) is a common gynecological condition primarily caused by Candida albicans. The excessive use of antifungal drugs has led to increased drug resistance, necessitating the search for alternative therapies. This study investigates the synergistic antifungal effects of cranberry proanthocyanidins (PACs) and probiotics against C. albicans. PACs were prepared at different concentrations (low, medium, high) and tested alone and in combination with multi-strain probiotics, including Lactobacillus rhamnosus and Lactobacillus plantarum. The antifungal activity of their cell-free supernatants (CFS) was also assessed. The results demonstrated that the combination of L. plantarum and medium-concentration PACs (L.p. + PACs M) significantly enhathe inhibitionition of C. albicans compared to individual treatments. In the Vaginal Microbiota Communities Analysis, this condition reduced C. albicans relative abundance to below 0.01%. This study highlights the potential of natural compounds and probiotics as alternative therapeutic strategies for VVC. Full article

(This article belongs to the Special Issue Focus on Cervicovaginal Health: Microbiome, Sexually Transmitted Infections, and Beneficial Microbes: 2nd Edition)

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Graphical abstract

13 pages, 231 KiB

Open AccessReview

New β-Lactam/β-Lactamase Inhibitor Combination Antibiotics

by Maria Sargianou, Panagiotis Stathopoulos, Christos Vrysis, Iva D. Tzvetanova and Matthew E. Falagas

Pathogens 2025, 14(4), 307; https://doi.org/10.3390/pathogens14040307 - 24 Mar 2025

Abstract

The growing problem of infections due to pathogens with antimicrobial resistance, especially Gram-negative bacteria, has led to the development of new β-lactam/β-lactamase inhibitor combination antibiotics. During the last 2 years from the writing of this article, cefepime/enmetazobactam, aztreonam/avibactam, and sulbactam/durlobactam were approved for [...] Read more.

The growing problem of infections due to pathogens with antimicrobial resistance, especially Gram-negative bacteria, has led to the development of new β-lactam/β-lactamase inhibitor combination antibiotics. During the last 2 years from the writing of this article, cefepime/enmetazobactam, aztreonam/avibactam, and sulbactam/durlobactam were approved for use in clinical practice. Cefepime/enmetazobactam targets extended-spectrum β-lactamase (ESBL)-producing Pseudomonas aeruginosa and Enterobacterales. It is indicated for the treatment of patients with complicated urinary tract infections, including pyelonephritis, in Europe and the USA, and also for hospital-acquired pneumonia, ventilator-associated pneumonia, and bacteremia associated with those infections (only in Europe). The antimicrobial spectrum of aztreonam/avibactam includes carbapenem-resistant Enterobacterales. Aztreonam/avibactam is indicated for the treatment of adult patients who suffer from complicated intra-abdominal infections, complicated urinary tract infections including pyelonephritis, hospital-acquired pneumonia, and ventilator-associated pneumonia due to aerobic Gram-negative infections with limited therapeutic options. Sulbactam/durlobactam, a combination of 2 β-lactamase inhibitors, is indicated for the treatment of adult patients with hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia due to the Acinetobacter baumannii–calcoaceticus complex [including carbapenem-resistant Acinetobacter baumannii (CRAB) infections]. Full article

(This article belongs to the Special Issue Beta Lactamases: A Weapon Against Antibiotics)

24 pages, 3008 KiB

Open AccessArticle

Genomic Insights into Vector–Pathogen Adaptation in Haemaphysalis longicornis and Rhipicephalus microplus

by Jin Liu, An Zhou, Qi Liu, Yang Gao, Shuhua Xu and Yan Lu

Pathogens 2025, 14(4), 306; https://doi.org/10.3390/pathogens14040306 - 23 Mar 2025

Abstract

As crucial vectors that transmit pathogens to humans and livestock, ticks pose substantial global health threats and economic burdens. We analyzed 328 tick genomes to explore the population’s genetic structure and the adaptive evolution of H. longicornis and R. microplus, two tick species [...] Read more.

As crucial vectors that transmit pathogens to humans and livestock, ticks pose substantial global health threats and economic burdens. We analyzed 328 tick genomes to explore the population’s genetic structure and the adaptive evolution of H. longicornis and R. microplus, two tick species with distinct life cycle characteristics. We observed distinct genetic structures in H. longicornis and R. microplus. Gene flow estimation revealed a closer genetic connection in R. microplus than H. longicornis, which was facilitated by geographical proximity. Notably, we identified a set of candidate genes associated with possible adaptations. Specifically, the immune-related gene DUOX and the iron transport gene ACO1 showed significant signals of natural selection in R. microplus. Similarly, H. longicornis exhibited selection in pyridoxal-phosphate-dependent enzyme genes associated with heme synthesis. Moreover, we observed significant correlations between the abundance of pathogens, such as Rickettsia and Francisella, and specific tick genotypes, which highlights the role of R. microplus in maintaining these pathogens and its adaptations that influence immune responses and iron metabolism, suggesting potential coevolution between vectors and pathogens. Our study highlights the vital genes involved in tick blood feeding and immunity, and it provides insights into the coevolution of ticks and tick-borne pathogens. Full article

(This article belongs to the Special Issue Tick-Borne Pathogens: Advanced Identification, Characterization, Transmission, and Prevalence Studies)

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10 pages, 2956 KiB

Open AccessArticle

One Health Approach to Brazilian Spotted Fever: Capybaras, Horses, and Rural Areas as Predictors for Human Disease

by Iara Giordano Rosa-Xavier, Adriano Pinter, Rogério Giuffrida, Alexander Welker Biondo, Louise Bach Kmetiuk and Vamilton Alvares Santarém

Pathogens 2025, 14(4), 305; https://doi.org/10.3390/pathogens14040305 - 23 Mar 2025

Abstract

(1) Background: Brazilian spotted fever (BSF) is a tick-borne disease that has occurred in several Brazilian regions, caused by Rickettsia spp. bacteria and mainly transmitted by Amblyomma ticks. Despite the high BSF lethality in several Brazilian endemic areas, predictors and associated risk factors [...] Read more.

(1) Background: Brazilian spotted fever (BSF) is a tick-borne disease that has occurred in several Brazilian regions, caused by Rickettsia spp. bacteria and mainly transmitted by Amblyomma ticks. Despite the high BSF lethality in several Brazilian endemic areas, predictors and associated risk factors remain to be fully established. Accordingly, the retrospective study herein aimed to assess BSF cases and associated factors in an endemic area of western São Paulo state. (2) Methods: Notified cases identified by the System for Epidemiological Surveillance of São Paulo (CVE), from January 2007 to December 2021, were gathered and analyzed by Logistic Multivariate Regression (LMR) to assess potential risk factors for BSF. (3) Results: Overall, 74/1121 (6.6%; 95% CI: 5.29–8.21) individuals were considered positive for BSF. Univariate analysis showed previous contact with capybaras (OR: 1.89; 95% CI: 1.0–3.55; p < 0.001) and raising horses (OR = 1.4; 95% CI: 0.66–2.67; p = 0.45), while LMR revealed living in rural areas (OR = 2.0; 95% CI: 1.02–3.73; p = 0.037) as an associated risk factor for BSF. (4) Conclusions: The results herein show that the geographically studied area still shows high occurrence of BSF, mostly for individuals living or visiting areas overlapping free-ranging capybaras. Full article

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9 pages, 1098 KiB

Open AccessCommunication

Physella acuta Confirmed as Intermediate Host of Posthodiplostomum sp. from Lake Alqueva, Portugal

by Maria Teresa Bispo, Isabel Larguinho Maurício, Pedro Manuel Ferreira, Silvana Belo and Manuela Calado

Pathogens 2025, 14(4), 304; https://doi.org/10.3390/pathogens14040304 - 23 Mar 2025

Abstract

Physella acuta is an invasive freshwater snail with a global distribution and a recognized role as an intermediate host for various trematodes, including Echinostoma spp. and Trichobilharzia physellae. In Portugal, P. acuta is commonly found in freshwater bodies such as Lake Alqueva, [...] Read more.

Physella acuta is an invasive freshwater snail with a global distribution and a recognized role as an intermediate host for various trematodes, including Echinostoma spp. and Trichobilharzia physellae. In Portugal, P. acuta is commonly found in freshwater bodies such as Lake Alqueva, the largest artificial reservoir in Europe. The lake’s creation has altered local ecosystems, influencing freshwater snail populations and migratory bird activity, which may contribute to the dispersal of trematode parasites. While P. acuta is present in the region, its role in trematode transmission remains unclear. This study investigated P. acuta as a potential intermediate host for trematodes in Lake Alqueva. Freshwater snails were collected from 18 sites, with cercarial shedding induced under artificial light. Infected snails were found in 2 of the 18 snail populations surveyed. A sequence analysis of the amplified ITS2 rDNA region confirmed the presence of Posthodiplostomum sp., implicating, for the first time, P. acuta as an intermediate host for this parasite in Portugal. This study highlights the need for further research on P. acuta’s role in trematode transmission and potential impact on local ecosystems to assess parasitic risks to veterinary and public health. Full article

(This article belongs to the Special Issue Emergence and Transmission of Climate-Sensitive Infectious Diseases in Europe)

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6 pages, 206 KiB

Open AccessBrief Report

Babesia Species Detected in Deer from Southwest England

by Hope Leverett, Ternenge T. Apaa, Harriet McFadzean and Nicholas Johnson

Pathogens 2025, 14(4), 303; https://doi.org/10.3390/pathogens14040303 - 22 Mar 2025

Abstract

Babesia species have been detected in deer across Europe, and deer grazing in the same location as livestock may increase the risk of transmission of species such as the parasite B. divergens. Bovine babesiosis and the cost of treatment increase the economic burden [...] Read more.

Babesia species have been detected in deer across Europe, and deer grazing in the same location as livestock may increase the risk of transmission of species such as the parasite B. divergens. Bovine babesiosis and the cost of treatment increase the economic burden on farmers. To determine the presence of Babesia species in wild deer populations in the counties of Devon and Somerset, Southwest England, blood samples were collected from red (Cervus elaphus) and fallow (Dama dama) deer as part of routine deer management during late 2022 and early 2023. Extracted DNA samples were tested for the presence of piroplasm DNA by polymerase chain reaction. Amplicons were sequenced to identify the species present in samples based on single-nucleotide polymorphisms within the 18S rRNA gene. Two species of Babesia were detected: a B. divergens/capreoli species detected in both red and fallow deer and a Babesia species related to B. odocoilei in a single fallow deer, a species that has been detected in deer across Great Britain. The presence of B. divergens/capreoli in deer blood from these areas provides evidence that wild deer could serve as a reservoir for this parasite within Southern England. Full article

(This article belongs to the Special Issue New Insights into the Pathogenesis, Immunology and Treatment of Human Babesiosis and Other Erythrocytic Pathogens)

17 pages, 4604 KiB

Open AccessArticle

N-Acetylcysteine as a Host-Directed Therapy Against Clarithromycin-Resistant Mycobacterium abscessus

by Shuqi Yang, Ying Zhang, Jinchuan Xu, Zhenyan Chen, Yang Ren, Yujiao Long, Xuejiao Huang, Juanxi Liu, Huan Huang, Shiqi Xie, Ruiqing Ma, Yajuan Dong, Xiaoyong Fan, Zhidong Hu and Feng Li

Pathogens 2025, 14(4), 302; https://doi.org/10.3390/pathogens14040302 - 21 Mar 2025

Abstract

(1) Background: The treatment of Mycobacterium abscessus (M. abscessus) infections resistant to clarithromycin (CLR) is highly challenging. Traditional non-tuberculous mycobacteria (NTM) chemotherapy may disturb the immune homeostasis of the host by increasing oxidative stress; therefore, host-directed immunotherapy is an alternative option [...] Read more.

(1) Background: The treatment of Mycobacterium abscessus (M. abscessus) infections resistant to clarithromycin (CLR) is highly challenging. Traditional non-tuberculous mycobacteria (NTM) chemotherapy may disturb the immune homeostasis of the host by increasing oxidative stress; therefore, host-directed immunotherapy is an alternative option for infections caused by M. abscessus. (2) Method: A clinical isolate of CLR-resistant M. abscessus was screened, and then the therapeutic effects of N-acetylcysteine (NAC) against CLR-resistant M. abscessus infection were evaluated in Tohoku Hospital Pediatrics-1 (THP-1) cells and murine models. RNA sequencing and Western blot were used to profile the protective immune responses induced by NAC. The contribution of candidate signaling pathways was confirmed by the corresponding inhibitor and agonist. (3) Results: NAC immunotherapy led to a significant reduction in bacterial loads both in THP-1 cells and murine infection models, which was associated with enhanced antioxidant effects and downregulation of apoptosis signal-regulating kinase 1 (ASK1)–mitogen-activated protein ki-nase/extracellular signal-regulated kinase 3/6 (MKK3/6)–p38 mitogen-activated protein kinase (MAPK)-mediated inflammatory immune responses. The inhibitor of p38 signaling mimicked the protective effect of NAC, while the agonist attenuated it, suggesting that the p38 pathway is crucial in NAC-mediated immune protection against M. abscessus infection. (4) Conclusion: Our study suggests that NAC could be used as a host-directed therapy agent against drug-resistant M. abscessus infection. Full article

(This article belongs to the Section Bacterial Pathogens)

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14 pages, 268 KiB

Open AccessReview

Influence of Occult Hepatitis B Infection on Blood Transfusion Safety and Its Countermeasures

by Meng Yi, Shuchang Dai, Lin Fang, Bo Pan, Bin Fan, Yiming Pan and Zhong Liu

Pathogens 2025, 14(4), 301; https://doi.org/10.3390/pathogens14040301 - 21 Mar 2025

Abstract

Occult hepatitis B infection (OBI) is a serious public health issue. Although a number of effective hepatitis B vaccines are available, hepatitis B still poses a threat to global public health. Patients with OBI are usually asymptomatic, but there may be active HBV [...] Read more.

Occult hepatitis B infection (OBI) is a serious public health issue. Although a number of effective hepatitis B vaccines are available, hepatitis B still poses a threat to global public health. Patients with OBI are usually asymptomatic, but there may be active HBV DNA present in their blood, leading to the risk of virus transmission during blood transfusions or organ transplantation, constituting a hazard to the health of recipients and increasing the risk of liver cirrhosis and liver cancer. Although China has progressed in the development of blood-screening technology, OBI is still a significant hidden danger to blood transfusion safety. Therefore, in blood screening and blood transfusion, strengthening the monitoring and management of OBI is crucial to ensure blood safety and protect public health. Full article

(This article belongs to the Special Issue Transfusion-Transmitted Infections)

11 pages, 221 KiB

Open AccessArticle

Unraveling Dysgeusia in SARS-CoV-2 Infection: Clinical and Laboratory Insights from Hospitalized COVID-19 Patients in Romania

by Elena Camelia Kouris, Sînziana Irina Mirea, Sigrid Covaci, Monica Luminița Luminos and Victor Daniel Miron

Pathogens 2025, 14(4), 300; https://doi.org/10.3390/pathogens14040300 - 21 Mar 2025

Abstract

Introduction: Dysgeusia has been regarded as a clinical feature associated with SARS-CoV-2 infection since the onset of the pandemic. The initial circulating variants were linked to the presence of dysgeusia; however, with the emergence of the Omicron variant, the incidence of dysgeusia has [...] Read more.

Introduction: Dysgeusia has been regarded as a clinical feature associated with SARS-CoV-2 infection since the onset of the pandemic. The initial circulating variants were linked to the presence of dysgeusia; however, with the emergence of the Omicron variant, the incidence of dysgeusia has decreased. The aim of this study was to identify the incidence and characteristics of patients with dysgeusia from the onset of the pandemic to the Omicron variant. Methods: We conducted a retrospective study from March 2020 to December 2021, among adult patients hospitalized with COVID-19 in the main infectious diseases hospital in Romania. Clinical and laboratory data were collected and interpreted in relation to the presence or absence of dysgeusia. Results: The incidence of dysgeusia was 32.0%, with the majority of cases (44.2%) occurring in patients with the Beta SARS-CoV-2 variant. Dysgeusia has been predominantly observed in mild to moderate cases of the disease. The presence of obesity and hypertension has been shown to be negatively associated with the development of dysgeusia (OR = 0.45, OR = 0.39, respectively). In patients with dysgeusia, inflammatory changes such as lymphopenia were significantly less frequently identified (OR = 0.22, p < 0.001), as were increased C-reactive protein (OR = 0.12, p < 0.001) and increased interleukin-1 (OR = 0.42, p = 0.002), increased fibrinogen (OR = 0.31, p < 0.001), and increased ferritin (OR = 0.27, p < 0.001) compared to patients without dysgeusia. The incidence of acute respiratory failure was higher in the dysgeusia group (71.2% vs. 28.8%, p < 0.001). This was accompanied by a milder management of patients with dysgeusia and a median duration of hospitalization that was two days shorter. Conclusions: The presence or absence of dysgeusia in patients with COVID-19 appears to correlate with both the inflammatory response and outcome. In the context of evolving circulating viral variants, which seem to be associated with a lower incidence of dysgeusia, continuous monitoring of patients who develop this disorder remains essential to clarify the pathophysiologic mechanisms involved and to assess the potential of dysgeusia as a predictor of the course of SARS-CoV-2 infection. Full article

(This article belongs to the Special Issue Feature Papers on the Epidemiology of Infectious Diseases)

20 pages, 4616 KiB

Open AccessArticle

Novel Techniques to Unravel Causative Bacterial Ecological Shifts in Chronic Urinary Tract Infection

by Catherine C. Y. Chieng, Qingyang Kong, Natasha S. Y. Liou, Mariña Neira Rey, Katie L. Dalby, Neil Jones, Rajvinder Khasriya and Harry Horsley

Pathogens 2025, 14(3), 299; https://doi.org/10.3390/pathogens14030299 - 20 Mar 2025

Abstract

Chronic urinary tract infection (UTI) presents with protracted lower urinary tract symptoms and elevated urinary leukocyte counts, but its bacterial etiological agents remain obscure. In this cross-sectional investigation, we aimed to unravel the role of the bladder microbiota in chronic UTI pathogenesis by [...] Read more.

Chronic urinary tract infection (UTI) presents with protracted lower urinary tract symptoms and elevated urinary leukocyte counts, but its bacterial etiological agents remain obscure. In this cross-sectional investigation, we aimed to unravel the role of the bladder microbiota in chronic UTI pathogenesis by studying the host immune response. Urine samples were collected from healthy controls (HT), chronic UTI patients who had not initiated treatment (PT) and those undergoing treatment (OT), then sorted into white blood cell (WBC) and epithelial cell (EPC) fractions. Bacteria associated with both fractions were identified by chromogenic agar culture coupled with mass spectrometry and 16S rRNA sequencing. Distinct WBC-exclusive bacteria were observed in the healthy population, but this pattern was less obvious in patients, plausibly due to epithelial shedding and breaching of the urothelial barrier. We also described a bacterial fingerprint guided by Escherichia that was able to stratify patients based on symptom severity. Clustering analyses of mean rank changes revealed highly statistically significant upward and downward ecological shifts in communities of bacteria between the healthy and diseased populations. Interestingly, many of the most abundant genera identified in sequencing remained stable when compared between the study cohorts. We concluded that reshuffling of the urinary microbiome, rather than the activity of a single known urinary pathogen, could drive chronic UTI. Full article

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13 pages, 792 KiB

Open AccessArticle

Clonal Dissemination of NDM-Producing Proteus mirabilis in a Teaching Hospital in Sousse, Tunisia

by Nadia Jaidane, Lamia Tilouche, Saoussen Oueslati, Delphine Girlich, Sana Azaiez, Aymeric Jacquemin, Laurent Dortet, Walid Naija, Abdelhalim Trabelsi, Thierry Naas, Wejdene Mansour and Rémy A. Bonnin

Pathogens 2025, 14(3), 298; https://doi.org/10.3390/pathogens14030298 - 20 Mar 2025

Abstract

Proteus mirabilis (P. mirabilis) is an opportunistic pathogen involved in urinary tract infections as well as various nosocomial infections. Emerging resistances to beta-lactams in this species complicates potential treatment since it is intrinsically resistant to colistin. Eleven isolates of carbapenem-non-susceptible P. [...] Read more.

Proteus mirabilis (P. mirabilis) is an opportunistic pathogen involved in urinary tract infections as well as various nosocomial infections. Emerging resistances to beta-lactams in this species complicates potential treatment since it is intrinsically resistant to colistin. Eleven isolates of carbapenem-non-susceptible P. mirabilis were identified in Sousse Hospital, Tunisia, from January 2018 to December 2022. MICs were determined and isolates were sequenced to determine their resistomes, sequence types, virulence factors, and their clonal relationships. Susceptibility testing showed that all isolates were resistant to carbapenems, aminoglycosides, fluoroquinolones, chloramphenicol, and the trimethoprim/sulfamethoxazole combination. They remained susceptible to the aztreonam/avibactam combination. All isolates produced NDM-1 carbapenemase and ArmA 16S rRNA methylase. In addition, one isolate co-produced the bla_VEB-6 gene. All isolates belonged to ST135, and phylogenetic analysis revealed that they were closely related. This study described the first outbreak of NDM-1-producing P. mirabilis in Tunisia. Full article

(This article belongs to the Section Bacterial Pathogens)

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8 pages, 652 KiB

Open AccessBrief Report

Ocular Symptoms in Pre- and Perimenopausal Woman Infected with Demodex spp.

by Danuta Kosik-Bogacka, Natalia Łanocha-Arendarczyk, Renata Pilarczyk, Daria Schneider-Matyka, Karolina Kot, Konrad Grzeszczak, Joanna Pyzia and Elżbieta Grochans

Pathogens 2025, 14(3), 297; https://doi.org/10.3390/pathogens14030297 - 20 Mar 2025

Abstract

The aim of this study was to determine the subjective ocular symptoms in pre- and perimenopausal women infected with Demodex folliculorum and D. brevis. Eyelashes were taken from pre- and perimenopausal women aged from 45 to 69 years (n = 253) and [...] Read more.

The aim of this study was to determine the subjective ocular symptoms in pre- and perimenopausal women infected with Demodex folliculorum and D. brevis. Eyelashes were taken from pre- and perimenopausal women aged from 45 to 69 years (n = 253) and younger women aged from 3 to 40 (n = 204) from the West Pomeranian Voivodeship located in Poland. The prevalence of mites was analyzed according to age and subjective ocular symptoms. Demodex spp. were detected in 75/253 (29.64%) of pre- and perimenopausal women and in 25/204 (12.25%) of younger women. Demodex folliculorum or D. brevis was observed in 72/252 (28.45%) and 1/253 (0.4%) of pre- and perimenopausal women, respectively, but the coinfection of D. folliculorum and D. brevis was noted in 2/253 (0.79%) of women. In young women, only D. folliculorum was detected. Single Demodex spp., multiple parasites, and numerous mites were reported in about 75%, 17%, and 8% of the examined women, respectively. There was a statistically significant relationship between Demodex spp. infestation and the occurrence of dryness of the eyes. Changes occurring in the female body during the pre- and perimenopausal periods lead to an increased incidence of Demodex spp. infestation. Women who report dryness of the eyes should have their eyelashes microscopically examined for Demodex spp. Full article

(This article belongs to the Section Parasitic Pathogens)

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14 pages, 3042 KiB

Open AccessArticle

Detection of Klebsiella pneumoniae in Veterinary and Food Matrices Using Loop-Mediated Isothermal Amplification

by Icía Bermúdez-Fornos, Alberto Cepeda, Alejandro Garrido-Maestu and Alexandre Lamas

Pathogens 2025, 14(3), 296; https://doi.org/10.3390/pathogens14030296 - 19 Mar 2025

Abstract

Klebsiella pneumoniae is an opportunistic human pathogen of high relevance due to its ability to acquire antibiotic resistance. This pathogen is included, along with Enterococcus faecium, Staphylococcus aureus, Acinetobacter baumanii, Pseudomonas aeruginosa, and Enterobacter spp., in the ESKAPE group, [...] Read more.

Klebsiella pneumoniae is an opportunistic human pathogen of high relevance due to its ability to acquire antibiotic resistance. This pathogen is included, along with Enterococcus faecium, Staphylococcus aureus, Acinetobacter baumanii, Pseudomonas aeruginosa, and Enterobacter spp., in the ESKAPE group, which consists of the most important bacterial pathogens resistant to antibiotics in clinical setups. Due to the importance of the rapid identification of infection-causative agents, a novel method for the rapid identification of K. pneumoniae was developed in the present work. This novel method was based on loop-mediated isothermal amplification (LAMP) and evaluated in real-time LAMP, as well as in end-point colorimetric LAMP. Additionally, the method was evaluated in two different clinical samples, namely, blood and urine, along with a food sample, namely, milk; four DNA purification protocols were also evaluated (thermal lysis, chelex, magnetic beads, and glass milk). The results revealed differences in the performance of the LAMP assays depending on the specific combination of the matrix–DNA purification protocol. Overall, the protocol reporting the best results in all the matrices was the one based on chelex, with which it was possible to reach an LOD50 below 10 CFU/mL after a short pre-enrichment step of 6 h in TSB. The method demonstrated reliability, sensitivity, and simplicity and could be performed by non-trained personnel thanks to the colorimetric format. Full article

(This article belongs to the Section Bacterial Pathogens)

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12 pages, 2093 KiB

Open AccessArticle

The Role of Caspase-1 and Caspase-4 in Modulating Gingival Epithelial Cell Responses to Aggregatibacter actinomycetemcomitans Infection

by Kartheyaene Jayaprakash Demirel, Alessandra Neves Guimaraes and Isak Demirel

Pathogens 2025, 14(3), 295; https://doi.org/10.3390/pathogens14030295 - 18 Mar 2025

Abstract

Periodontitis is a chronic inflammatory disease characterized by bacterial infection and immune dysregulation. Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) is a key pathogen linked to disease progression. Caspase-1 and caspase-4 regulate inflammasome activation and cytokine release, yet their roles in gingival epithelial immunity [...] Read more.

Periodontitis is a chronic inflammatory disease characterized by bacterial infection and immune dysregulation. Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) is a key pathogen linked to disease progression. Caspase-1 and caspase-4 regulate inflammasome activation and cytokine release, yet their roles in gingival epithelial immunity remain unclear. The aim of this study was to elucidate the involvement of caspase-1 and caspase-4 in regulating the immune response to A. actinomycetemcomitans infection in gingival epithelial cells. Human gingival epithelial cells (Ca9-22) and caspase-1- and caspase-4-deficient cells were infected with A. actinomycetemcomitans for 24 h. Inflammatory mediator release was analyzed using Olink proteomics. Bacterial colonization and invasion were assessed using fluorescence-based assays and gentamicin protection assays. Caspase-1- and caspase-4-deficient cells showed significantly altered cytokine and chemokine profiles after infection with A. actinomycetemcomitans, showing reduced IL-17C and IL-18 release. We also found an increased release of TGF-α and LIF from caspase-4-deficient cells, along with elevated levels of the chemokines IL-8, CXCL9, and CXCL10. Additionally, both caspase-1- and caspase-4-deficient cells showed increased bacterial colonization and invasion, particularly in caspase-4-deficient cells. These findings suggest that caspase-1 and caspase-4 play distinct yet essential roles in gingival epithelial immunity, regulating cytokine release, barrier integrity, and defense against A. actinomycetemcomitans colonization. Full article

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16 pages, 6026 KiB

Open AccessArticle

Molecular Characterization and Antimicrobial Resistance Evaluation of Listeria monocytogenes Strains from Food and Human Samples

by Annamaria Castello, Vincenzina Alio, Marina Torresi, Gabriella Centorotola, Alexandra Chiaverini, Francesco Pomilio, Ignazio Arrigo, Anna Giammanco, Teresa Fasciana, Marco Francesco Ortoffi, Antonietta Gattuso, Giuseppa Oliveri, Cinzia Cardamone and Antonella Costa

Pathogens 2025, 14(3), 294; https://doi.org/10.3390/pathogens14030294 - 18 Mar 2025

Abstract

Listeria monocytogenes is an important foodborne pathogen, markedly persistent even in harsh environments and responsible for high hospitalization and mortality rates. The aim of the present study was to detect the strains circulating in Sicily over a five-year period and characterize their antimicrobial [...] Read more.

Listeria monocytogenes is an important foodborne pathogen, markedly persistent even in harsh environments and responsible for high hospitalization and mortality rates. The aim of the present study was to detect the strains circulating in Sicily over a five-year period and characterize their antimicrobial resistance profiles. The key element of this study was the sharing of data among various entities involved in food control and clinical surveillance of listeriosis in order to develop an integrated approach for this pathogen. A total of 128 isolates were analyzed, including 87 food-source strains and 41 clinical specimens. Whole-genome sequencing (WGS) was performed for sequence type (ST) and clonal complex (CC) identification through multilocus sequence typing (MLST) analysis. Antimicrobial resistance was assessed using the Kirby–Bauer method. The majority of strains belonged to serotype IVb (34/41 and 53/87 of clinical and food-source isolates, respectively) and were subtyped as CC2-ST2 (28/34 and 41/53 of clinical and food-source isolates respectively). Most of the isolates were susceptible to the main antimicrobials recommended for treatment of listeriosis. Resistance (R) and intermediate resistance (I) percentages worthy of attention were found against oxacillin (R: 85.9%) and clindamycin (I: 34.6%) in the food-source isolates and trimethoprim/sulfamethoxazole (R: 29.23%) in the clinical isolates. Also, 7.7% of the food-source isolates were multidrug resistant. Our results highlight how the punctual comparison between food and clinical strains is an essential tool for effectively tracking and preventing foodborne outbreaks. Full article

(This article belongs to the Section Bacterial Pathogens)

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25 pages, 914 KiB

Open AccessReview

Unlocking the Interactions Between the Whole-Body Microbiome and HPV Infection: A Literature Review

by Myrto Papamentzelopoulou and Vassiliki C. Pitiriga

Pathogens 2025, 14(3), 293; https://doi.org/10.3390/pathogens14030293 - 18 Mar 2025

Abstract

The human microbiome plays a vital role in maintaining human homeostasis, acting as a key regulator of host immunity and defense mechanisms. However, dysbiotic microbial communities may cause disruption of the symbiotic relationship between the host and the local microbiota, leading to the [...] Read more.

The human microbiome plays a vital role in maintaining human homeostasis, acting as a key regulator of host immunity and defense mechanisms. However, dysbiotic microbial communities may cause disruption of the symbiotic relationship between the host and the local microbiota, leading to the pathogenesis of various diseases, including viral infections and cancers. One of the most common infectious agents causing cancer is the human papilloma virus (HPV), which accounts for more than 90% of cervical cancers. In most cases, the host immune system is activated and clears HPV, whereas in some cases, the infection persists and can lead to precancerous lesions. Over the last two decades, the advent of next-generation sequencing (NGS) technology and bioinformatics has allowed a thorough and in-depth analysis of the microbial composition in various anatomical niches, allowing researchers to unveil the interactions and the underlying mechanisms through which the human microbiota could affect HPV infection establishment, persistence, and progression. Accordingly, the present narrative review aims to shed light on our understanding of the role of the human microbiome in the context of HPV infection and its progression, mainly to cervical cancer. Furthermore, we explore the mechanisms by which the composition and balance of microbial communities exert potential pathogenic or protective effects, leading to either HPV persistence and disease outcomes or clearance. Special interest is given to how the microbiome can modulate host immunity to HPV infection. Lastly, we summarize the latest findings on the therapeutic efficacy of probiotics and prebiotics in preventing and/or treating HPV infections and the potential of vaginal microbiota transplantation while highlighting the significance of personalized medicine approaches emerging from NGS-based microbiome profiling and artificial intelligence (AI) for the optimal management of HPV-related diseases. Full article

(This article belongs to the Special Issue Oncogenic Viruses: Advances in Molecular Diagnosis, Prevention Strategies and Therapy)

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13 pages, 3504 KiB

Open AccessArticle

Genomic Diversity, Virulome, and Resistome of Streptococcus agalactiae in Northeastern Brazil: Are Multi-Host Adapted Strains Rising?

by Vinicius Pietta Perez, Luciana Roberta Torini, Fernanda Zani Manieri, Suellen Bernardo de Queiroz, Jorhanna Isabelle Araujo de Brito Gomes, Lauro Santos Filho, Eloiza Helena Campana, Celso Jose Bruno de Oliveira, Eduardo Sergio Soares Sousa and Ilana Lopes Baratella Cunha Camargo

Pathogens 2025, 14(3), 292; https://doi.org/10.3390/pathogens14030292 - 17 Mar 2025

Abstract

Streptococcus agalactiae, known as group B streptococci (GBS), colonizes the digestive and genitourinary tracts and causes neonatal diseases and infections in immunocompromised and elderly individuals. GBS neonatal disease prevention includes intrapartum antibiotic prophylaxis. We characterized 101 GBS isolates obtained from patients in [...] Read more.

Streptococcus agalactiae, known as group B streptococci (GBS), colonizes the digestive and genitourinary tracts and causes neonatal diseases and infections in immunocompromised and elderly individuals. GBS neonatal disease prevention includes intrapartum antibiotic prophylaxis. We characterized 101 GBS isolates obtained from patients in João Pessoa, northeastern Brazil, owing to the need to develop and implement vaccines to prevent GBS infections. Capsular types were determined using multiplex-PCR, and antibiotic susceptibility profiles were determined using disc diffusion or the gradient strip method. Clonal diversity was evaluated using pulsed-field gel electrophoresis. Fourteen selected isolates had the genome sequenced and evaluated for virulence and resistance genes. The GBS population had high clonal diversity, with serotype Ia and V prevalence. Among the sequenced isolates, we detected antibiotic resistance genes (ant(6)-Ia, catA8, ermA, ermB, lsaE, lsnuB, mefA/msrD, tetM, tetO, and tetS), several virulence genes, and mobile genetic elements integrated into the chromosome. The most frequent Sequence Type (ST) was ST144, followed by ST196, ST28, ST19, ST12, ST23, ST103, and the new ST1983 (CC103). Phylogenetically, ST103 and ST1983 were distant from the other STs. Our data revealed highly virulent GBS strains in this population and a new ST that could be related to a zoonotic origin. Full article

(This article belongs to the Section Bacterial Pathogens)

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17 pages, 2967 KiB

Open AccessSystematic Review

Can Bacteriophages Be Effectively Utilized for Disinfection in Animal-Derived Food Products? A Systematic Review

by Rafail Fokas, Zoi Kotsiri and Apostolos Vantarakis

Pathogens 2025, 14(3), 291; https://doi.org/10.3390/pathogens14030291 - 16 Mar 2025

Abstract

Food safety is a paramount public health concern, particularly with the rise of antimicrobial-resistant bacteria. This systematic review explores the efficacy of bacteriophages as a novel and environmentally sustainable approach to controlling multi-resistant and non-resistant bacterial pathogens in animal-derived food products. Following PRISMA [...] Read more.

Food safety is a paramount public health concern, particularly with the rise of antimicrobial-resistant bacteria. This systematic review explores the efficacy of bacteriophages as a novel and environmentally sustainable approach to controlling multi-resistant and non-resistant bacterial pathogens in animal-derived food products. Following PRISMA guidelines, data from multiple studies were synthesized to evaluate bacteriophage applications across diverse food matrices, including beef, poultry, seafood, and dairy. The findings highlight significant variability in bacteriophage efficacy, influenced by factors such as food matrix properties, bacterial strains, and application methods. Phage cocktails and their combination with thermal treatments consistently demonstrated superior bacterial reduction compared to single-phage applications, which yielded variable results. Interestingly, the absence of a clear dose-response relationship underscores the need for a more detailed understanding of phage-host interactions and environmental influences. This review addresses a critical gap in the literature by advocating for matrix-specific, targeted phage applications over generalized approaches. Additionally, it underscores the transformative potential of bacteriophages as sustainable alternatives to chemical disinfectants in modern food safety practices. These insights provide a framework for future research aimed at optimizing bacteriophage efficacy and scaling their application in real-world food production systems. Full article

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