Search Results (1,909)

Bacillus anthracis is endemic in the United States causing periodic outbreaks in wildlife and domestic animals. Currently, human anthrax cases in the U.S. are rare but were common in the 1950s–1960s due to industrial work with imported B. anthracis-contaminated animal products. Multiple-locus variable-number tandem repeat analysis (MLVA) initially differentiated B. anthracis into 89 genotypes and two major clades. Recently, whole-genome sequencing (WGS) was implemented to differentiate B. anthracis which allows for higher resolution and can eliminate risk of homoplasy. To assess the molecular diversity of U.S.-established isolates, we performed MLVA and WGS on 81 B. anthracis isolates from domestic animals or soil. By MLVA, most isolates (n = 58, 72%) were in the Western North America (WNA)/A1.a cluster. Isolates were also observed in the Ames (A3.b), Vollum (A4), and Group B clusters. Using WGS, two major clades (A and B) and four clusters (WNA, Ames, Vollum, Group B) were identified. The four WGS clusters correlated with previously established MLVA clusters (A1a, A3b, A4, and B1, respectively). Further differentiation of the WNA cluster showed that isolates collected from the same state generally clustered together and more broadly by region (west, central, Texas). In the current study, we provide an update on the genetic diversity of domestically established B. anthracis strains using MLVA and WGS. WGS was able to provide additional differentiation, particularly within the WNA cluster, which can lend assistance in epidemiological investigations. Full article

Recent foodborne outbreaks by Salmonella Typhimurium associated with the consumption of ‘Maradol’ papaya have prompted an assessment of the pathogen’s behavior with regard to the fruit. The objective of this research was to assess the survival and possible internalization of S. Typhimurium in inoculated ‘Maradol’ papaya harvested at two maturity stages and stored for various days at 11 °C and 24 °C. The physicochemical analysis on fruit included firmness (N), total soluble solids (%), and pH. The location of S. Typhimurium in fruit exocarp and mesocarp tissues was observed using confocal laser scanning microscopy (CLSM). Results indicated that the high temperature (24 °C) was the most important factor for the survival of S. Typhimurium. At this same temperature, it was the variable firmness that was the most affected, regardless of storage days, whether inoculated or not. The principal component analysis (PCA) separated the data into two components that explained 57% of the variance. PC1 linked higher S. Typhimurium populations with declining firmness, TSS, and exocarp pH were found in fruit stored at 24 °C, whereas PC2 was associated with moderate physicochemical changes at 11 °C. The CLSM observations confirmed superficial colonization of the bacteria on papaya fruit rather than an internalization but only at 24 °C, regardless of ripening stage throughout the 7 days sampling period. Maintaining the cold chain is essential to mitigate the risk of salmonellosis in papaya. Full article

The global rise in multidrug-resistant (MDR) fungal pathogens has positioned Candida auris and Candida glabrata as major threats to public health. In recent years, these pathogens have increasingly been reported beyond traditional hospital settings, including neonatal intensive care units, long-term care facilities, oncology wards, and post-pandemic critical care environments. International surveillance bodies, including the Centers for Disease Control and Prevention (CDC), European Centre for Disease Prevention and Control (ECDC), World Health Organization (WHO), and regional monitoring networks, have documented escalating antifungal resistance, complex outbreak dynamics, and persistent gaps in infection control implementation. C. auris has emerged as a major etiological agent of healthcare-associated outbreaks, particularly in intensive care and neonatal units. Surveillance data indicate that a high proportion of C. auris isolates exhibit resistance to azoles, often exceeding 80% in some regions, while echinocandin resistance remains variable. Resistance patterns have evolved from predominantly azole resistance to broader multidrug-resistant phenotypes, including treatment-emergent echinocandin resistance. Six genetically distinct clades (I–VI) have been identified, with Clades I, III, and IV associated with large-scale outbreaks, whereas available data suggests that Clades II, V, and VI are more geographically restricted, although evidence for the recently described clades remains limited. C. glabrata is increasingly recognized as a major cause of invasive candidiasis, with rising resistance reported across multiple regions. While reduced azole susceptibility was historically predominant, emerging evidence highlights rising dual azole–echinocandin resistance, adaptive microevolution during antifungal therapy, and biofilm-associated tolerance mechanisms. Despite these advances, significant gaps persist in global resistance surveillance and in the mechanistic understanding of virulence and antifungal adaptation. Current mitigation strategies include antifungal stewardship programs, expanded resistance testing, and strengthened surveillance systems. Advances in rapid diagnostic technologies such as matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) mass spectrometry, polymerase chain reaction (PCR)-based assays, and genomic surveillance have improved pathogen identification and outbreak detection, although accessibility remains limited in resource-constrained settings. This review examines emerging epidemiological, genomic, and antifungal resistance trends in C. auris and C. glabrata and highlights key priorities for improving diagnosis, surveillance, stewardship, and management of multidrug-resistant Candida infections. Full article

High-throughput sequencing (HTS) was applied to investigate the virome of European beech (Fagus sylvatica) from asymptomatic leaves and symptomatic leaves exhibiting chlorosis, line patterns and malformation. Total RNA extracted from six samples, including herbarium material collected in 1967 and 1968 and contemporary samples from France, Germany, and The Netherlands, was subjected to Illumina sequencing followed by de novo assembly, sequence similarity searches and phylogenetic analyses. In each sample, contigs belonging to a previously undescribed virus within the genus Carlavirus were obtained. The virus was tentatively named beech carlavirus. No additional virus contigs were detected in the samples. The detection of the virus over more than five decades and in three European countries indicates its long-term and a probable wider occurrence and circulation. Moreover, its prolonged unnoticed presence suggests that it does not induce noticeable and acute disease outbreaks. These findings underscore the value of integrating historical and recent field samples through collaborative data sharing to improve insight into virus diversity and ecology in forest trees. Full article

Background/Objectives: Vancomycin-resistant (VRE) and vancomycin-variable (VVE) Enterococcus spp. represent an increasing clinical challenge due to limited treatment options and the potential for undetected dissemination of such resistance genes. Data on Enterococci genomic epidemiology in healthcare settings remain rather limited. Our study aimed to investigate vancomycin resistance determinants in Enterococcus spp., clonal structure, and occurrence of VVE using whole-genome sequencing (WGS) in Latvia. Methods: Clinical isolates collected from hospitalised patients in two tertiary-level hospitals in Latvia (2021–2024) were analysed using WGS following routine laboratory identification. Vancomycin resistance determinants were identified in silico, along with MLST and cgMLST genotyping. Results: Of 532 sequenced isolates, 482 met the quality and inclusion criteria. E. faecalis (56.64%) and E. faecium (40.25%) predominated. Among 125 isolates carrying vancomycin resistance genes, vanB (54.40%) was the most frequent, followed by vanA (38.20%) and vanC (6.40%); vanC was restricted to E. gallinarum and E. casseliflavus. Vancomycin resistance was more prevalent in E. faecium (51.03%) than in E. faecalis (6.59%). cgMLST identified outbreak clusters among E. faecium ST80 and ST78 with complex type-specific resistance patterns and hospital specificity. E. faecalis showed polyclonal endemicity with the vanB gene present in different clades. Three (0.62%) vancomycin-variable E. faecium (VVE) isolates were identified in one hospital, harbouring vanA-type gene clusters comprising vanHAX but lacking the sensory gene vanS and the regulatory gene vanR. Conclusions: The VanB gene predominated in both hospitals, driven by clonal expansion of hospital-adapted E. faecium ST80/ST78, contrasting with earlier vanA predominance in Europe but aligning with recent regional vanB trends. The detection of VVE highlights clinically relevant genotype–phenotype discordance, underscoring the importance of integrating genomic surveillance with routine phenotypic testing to detect cryptic resistance and guide effective antimicrobial therapy. Full article

Background: Dengue fever has emerged as a major public health concern in Bangladesh, with increasing incidence and geographic spread of outbreaks in recent years. This study aimed to investigate the lagged and non-linear associations between climatic factors and dengue incidence across all eight administrative divisions of Bangladesh from 2014 to 2025. Materials and Methods: An ecological time-series design was employed using monthly dengue case data (n = 741,338) and meteorological variables. A generalized additive model (GAM) with a negative binomial distribution was applied to account for overdispersion and capture complex relationships. Descriptive analysis was conducted to assess spatial heterogeneity, and choropleth maps were constructed to visualize the spatial distribution and regional variation in dengue burden across the country. Cross-correlation analysis was performed to identify significant lagged associations between climatic variables and dengue incidence. Results: Descriptive analysis showed substantial spatial heterogeneity, with the highest incidence observed in Dhaka (6.53 per 100,000) and the lowest in Sylhet (0.21 per 100,000). Choropleth maps illustrated distinct spatial distribution and regional variation in dengue burden across the country. Cross-correlation analysis identified significant lagged associations for temperature and rainfall (lag 1–3 months), humidity (lag 1–2 months), and wind speed (lag 2–3 months). The final GAM explained 88.6% of the deviance in dengue incidence (AIC = 7404.15; dispersion = 0.767). The approximate significance of smooth terms revealed that temperature at a lag of 1 month (p < 0.001, edf = 12.28), rainfall at a lag of 3 months (p < 0.001, edf = 2.85), and wind speed at a lag of 2 months (p < 0.001, edf = 2.25) were highly significant non-linear predictors of dengue transmission. Relative humidity was not significantly associated with dengue incidence. Non-linear effects revealed peak dengue risk at temperatures between 25 and 30 °C and moderate rainfall (~10 mm), particularly during monsoon months (June–October). A strong autoregressive effect indicated that prior dengue incidence significantly influenced current transmission. Conclusions: Overall, dengue transmission in Bangladesh is driven by complex, lagged, and non-linear interactions between climatic variables, seasonality, and regional factors. These findings provide critical evidence for climate-based early warning systems, enhance outbreak prediction, and inform evidence-based vector control strategies. Full article

The fruit-piercing moth, Eudocima phalonia (Lepidoptera: Erebidae), is a widespread pest in the Pacific region and has recently become economically important again in New Caledonia due to increasingly frequent outbreaks. Improving knowledge of its biology is essential for developing effective monitoring and management strategies. This study aimed to (i) establish a detailed laboratory rearing protocol, (ii) characterize its life cycle and reproductive traits under controlled conditions, and (iii) explore associations between larval coloration, developmental parameters, and seasonal population dynamics. Laboratory colonies were maintained over multiple generations, and field monitoring was conducted across several sites over three years. Larval colour polymorphism was documented, and statistical analyses (ANOVA and linear models) revealed significant associations between larval coloration and pupal morphological traits. However, these results should be interpreted cautiously due to unbalanced sample sizes and the observational nature of the dataset. Differences between sexes in several developmental traits were also observed. Field data showed marked seasonal variation in population abundance. This study provides a detailed rearing protocol and baseline biological data for Eudocima phalonia in New Caledonia, supporting future experimental and applied research. Full article

The southern pine beetle (SPB) is a serious pest of pine forests from Central America to the eastern United States, with a recent range expansion into the northeastern United States. Efforts to detect and monitor SPB activity began in 1960 as part of an overall integrated pest management system to limit its impact to southern pine forests. The ubiquity of SPB’s pine hosts in the southern United States, in the form of plantations and natural mixed stands, along with the regular occurrence of SPB outbreaks over a vast region, makes SPB a leading driver of overall forest health across this region. We review the past and current methodology for collecting SPB-related pine mortality and outbreak data using aerial and ground survey techniques and remote sensing via satellite imagery. We show how historical and ongoing measurements of SPB abundance, from pheromone-baited traps and aerial surveys, are used to forecast near-term probabilities of outbreaks with a statistical model (actualized through a public URL) that captures the natural tendency of SPB populations to be very high or very low. Insect forecasts can also be combined with maps of the host distributions to generate predictions of short-term regional risks and longer-term tree mortality forecasts via the US Forest Service’ National Insect and Disease Risk Map (NIDRM). Because the measurements of insect abundance and impact outcomes have become part of continuing forest management operations, statistical models can continue to be improved and there is self-reinforcing feedback between models and management. Improved understanding and monitoring of prominent insect pests that impact abundant tree species is a pathway to managing forest health more broadly. Full article

Foodborne pathogens pose a major challenge for public health, food safety regulation, and industrial quality control. Effective surveillance, outbreak tracing, and early warning for foodborne microbial contamination require rapid, reliable detection methods. Conventional culture-based methods are still essential for regulatory confirmation since they recover viable isolates and support downstream verification. However, their long turnaround time, labor-intensive procedures, and limited throughput restrict their use in rapid screening and on-site testing. In recent years, immunological assays, nucleic acid amplification and recognition methods, biosensors, microfluidic systems, CRISPR-Cas platforms, mass spectrometry, sequencing technologies, and artificial intelligence-assisted analysis have expanded the detection toolbox. These methods improve speed, sensitivity, portability, and multiplexing capacity, but their performance still depends on food-matrix properties, sample pretreatment, and application conditions. This review compares representative methods in terms of analytical principle, sample pretreatment, sensitivity, specificity, assay time, viable-cell discrimination, field applicability, and standardization potential. In our opinion, culture-based methods are central for confirmation, while emerging technologies are better suited for rapid screening, integrated analysis, and point-of-need testing. Nevertheless, matrix interference, limited validation in naturally contaminated samples, insufficient viable/dead-cell discrimination, and weak cross-platform consistency remain key barriers to routine use. Full article

African swine fever virus (ASFV) is an evolving threat to global swine health and food security, driven by its complex epidemiology, multi-host transmission cycles, and ongoing spread across countries. This review summarizes the global scenario and transmission pathways of ASFV, highlighting the outbreaks associated with evolving risk patterns to support effective disease prevention and control. ASF has been reported in pig-producing regions across Africa, Europe, and, more recently, Asia, largely driven by the spread of genotype II strains. The virus is transmitted through direct contact with infected pigs or pig-products, indirectly via contaminated materials, and through soft ticks of the genus Ornithodoros spp., with epidemiological patterns varying according to wildlife reservoirs and regional factors. Control measures mainly rely on early detection, movement control, strict quarantine, robust biosecurity measures, and international trade regulations. Despite significant advances, persistent challenges, including the absence of a widely available commercial vaccine, long-term stability of the virus, human activities, and inconsistencies in global response capacities, continue to hinder disease eradication efforts. This review underscores the need for transnational strategies and policies that integrate economically sustainable disease management systems and reduce the long-term impact of ASFV. Full article

Background: The World Health Organization (WHO) declared a pandemic due to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the etiologic agent responsible for Coronavirus Disease 2019 (COVID-19). Although case numbers declined after the initial outbreak, Brazil experienced slight increases in COVID-19 cases in 2024 and 2025, underscoring the persistent need for effective therapeutic interventions. Recently, proxalutamide—an androgen receptor antagonist—has been proposed as a potential therapeutic agent against COVID-19, as supported by several clinical studies. Methods: In the present work, we aimed to elucidate the molecular interactions between proxalutamide and key proteins involved in the viral fusion and replication processes of SARS-CoV-2. Computational techniques, including molecular docking and molecular dynamics simulations, were employed. Results: Our analyses indicated a high success rate, with stable conformations and favorable binding affinity values for ACE2 (−8.90 kcal/mol) and TMPRSS2 (−9.28 kcal/mol), resulting in strong docking scores. Moreover, molecular dynamics simulations confirmed the stability of these complexes, as evidenced by consistent mean square deviation values, low structural flexibility, a stable radius of gyration, and maintained surface rigidity over a 100 ns simulation period. Conclusions: These combined docking and dynamics results suggest that proxalutamide interacts firmly with the active sites, indicating high binding affinity that may interfere with SARS-CoV-2 entry. Nevertheless, experimental validation and rigorous safety assessments are warranted to confirm this potential. Full article

Recently, a strain of Streptococcus agalactiae serotype Ia sequence type 7 clonal complex 1 (SaIa ST7 CC1) has emerged in Latin American tilapia aquaculture as an international threat. This study evaluated outbreaks of acute streptococcosis occurring between 2021 and 2025 on commercial Nile tilapia (Oreochromis niloticus) farms in six Latin American countries, aiming to integrate molecular, clinical, pathological, and environmental data. In total, 360 moribund or recently dead fish at various production stages (larvae/fry, pre-grow-out, and grow-out) were examined, and 25 S. agalactiae isolates were serotyped and subjected to real-time PCR analysis, multilocus sequence typing (MLST), virulence and antimicrobial resistance gene profiling, and antimicrobial susceptibility testing. All isolates belonged to SaIa and shared the same ST7 CC1 MLST profile, forming a highly homogeneous cluster with reference SaIa ST7 CC1 strains previously isolated from tilapia farms in Asia. These results are consistent with the regional spread of a single clonal line. At the larval and fry stages, SaIa ST7 CC1 was associated with hyperacute septicemia, gastrointestinal hemorrhage, and frequent intestinal intussusception, whereas in pre-grow-out and grow-out fish, neurological signs were more prominent, followed by ocular signs, systemic hemorrhages, and coelomic lesions. Histopathological examination showed profuse colonization of the brain, spleen, liver, and intestine by Gram-positive cocci, accompanied by marked acute circulatory and inflammatory lesions and few chronic granulomatous responses, consistent with a rapidly progressing, highly aggressive infectious process. All outbreaks occurred during extended periods of warm water (>32 °C), with large day–night thermal gradients and reduced dissolved oxygen, suggesting that thermal stress may exacerbate disease expression in affected systems. All SaIa ST7 CC1 strains exhibited phenotypic susceptibility to florfenicol and amoxicillin, whereas 84% (21/25) and 100% (25/25) exhibited intermediate susceptibility to oxytetracycline and enrofloxacin, respectively. In total, 5 of the 21 isolates (23.8%) with intermediate susceptibility to oxytetracycline carried tetracycline resistance genes (tetM, tetO). These findings identify SaIa ST7 CC1 as a clinically significant emerging threat associated with thermally facilitated and geographically expanding streptococcosis in tilapia production in Latin America. Immediate priorities include screening imported broodstock using MLST or whole-genome sequencing (WGS), harmonized regional molecular surveillance, climate-adaptive farm management practices, prudent antimicrobial use, and serotype-matched vaccination and breeding strategies that improve both disease and heat resilience. Full article

Highly pathogenic avian influenza (HPAI) H5N1 viruses of the goose/Guangdong (Gs/GD) lineage have driven a global panzootic since 2020, with clade 2.3.4.4b establishing sustained transmission in wild birds. In South America, early outbreaks were largely associated with the North American-derived B3.2 genotype, which showed limited diversification after its introduction. Here, we report the genomic characterization of eight H5N1 viruses detected in Uruguay during the reemergence of avian influenza in February–March 2026. Complete genomes were obtained from wild birds exhibiting neurological signs, predominantly Coscoroba coscoroba. All viruses belong to clade 2.3.4.4b but exhibit a reassortant genomic constellation distinct from B3.2. The HA, NA, and MP segments retain the Eurasian backbone, whereas internal genes derive from both South American and North American low-pathogenicity avian influenza lineages. PB2 variation distinguishes two closely related viral groups differing in PB2 origin, whereas the remaining genomic segments retain a shared background. Sequence variation in the neuraminidase gene reduced the sensitivity of a widely used N1-specific RT-qPCR assay, highlighting limitations of existing diagnostic tools during viral evolution. These findings confirm the presence of reassortant H5N1 viruses in Uruguay and, together with recent reports from Argentina and Brazil, support an emerging pattern of genomic diversification in southern South America. Full article

Nipah virus (NiV) is an animal-borne RNA virus of the genus Henipavirus that poses a significant global health threat. This threat is driven by the virus’s high mortality rate, its capacity to cause epidemics, and the lack of licensed therapeutic interventions or vaccines. Since its initial identification during the 1998–1999 outbreak in Malaysia and Singapore, recurrent episodes have occurred primarily in Bangladesh and India, with mortality rates frequently exceeding 70%. Fruit bats of the genus Pteropus serve as the biological host for the virus. Transmission to humans occurs via contact with infected wildlife, consumption of contaminated products, such as freshly harvested date palm sap, or direct person-to-person exposure. Other modes of transmission, such as transplacentally or via breast milk, are still under investigation. The clinical presentation of NiV infection varies widely, from mild flu-like symptoms to life-threatening respiratory disease and acute encephalitis. It frequently attacks the nervous system, which can lead to coma, permanent neurological damage, or relapsing encephalitis. The virus enters host cells via ephrin-B2/B3 receptors, enabling systemic dissemination and infiltration of the central nervous system. Diagnosis relies primarily on RT-PCR and serological assays, and virus isolation requires high-containment laboratories. Management remains largely supportive, as no approved antiviral therapy exists. Experimental agents, such as remdesivir, favipiravir, and monoclonal antibodies such as m102.4, have shown promise in preclinical studies. Multiple vaccine platforms—including subunit, viral vector, mRNA, and nanoparticle-based approaches—are under development, though none is yet licensed for human use. Strengthened surveillance, infection control measures, and continued research are essential to mitigate the threat posed by this emerging pathogen. This review summarizes current knowledge on NiV, including its virology, epidemiology, pathogenesis, transmission, and recent progress in therapeutic and vaccine development. Full article

Asymptomatic pharyngeal Neisseria meningitidis (Nm) carriage is seen in >30% of sexually transmitted infection (STI) clinic attendees. With increasing reports of Nm urethritis and STI-related invasive disease outbreaks, longitudinal assessment and genomic characterization of Nm among patients at an urban STI clinic population in Columbus, Ohio, was undertaken. This study determined the genomic basis of oropharyngeal, urogenital and rectal Nm isolates carried by patients presenting for care. Cultures using media selective for Neisseria spp., Nm-specific PCR screening of colonies with oxidase-positive Gram-negative diplococci, PCR-based genogrouping and whole-genome sequencing of confirmed Nm were performed. Overall, genomic data of 453 oropharyngeal, 10 urethral, 5 rectal and 1 cervical Nm isolate were obtained between January 2018 and December 2019. Among oropharyngeal Nm isolates, genogrouping identified 37.7% as cnl (capsule null locus), 28% B, 13.5% E, 10.8% Z, 2.6% C and 2.6% Y. However, the cps locus was inactivated in ≥80% of isolates with specified genogroups. The major clonal complexes (ccs) were cc53, cc32, cc41/44, cc1157, cc198 and cc4821. Two oropharyngeal, one rectal and three urethral isolates belonged to the ST-11 Nm urethritis clade (NmUC). Group Y ST-1466 Nm, recently linked to global urogenital and systemic infections, was also identified in the oropharynx. Full article