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Not many pathogens are as uniquely adapted as Streptococcus pyogenes to cause a variety of infections ranging from strep throat to serious flesh-eating skin infections. Yet, scientists, to date, have had limited knowledge into the extent of diseases strep caused in the past. In a new study, Valverde et al. found the signature of strep in the tooth of a mummified individual from a sea of sequencing data and traced the past of the pathogen.

Donovanosis usually causes genital ulcers with a distinct clinical appearance. The condition has been a problem in many developing countries, but recent years have seen a significant global decline in prevalence. It is well on the way to being eradicated. Donovanosis has been known under many different terminologies, and there is still debate about how the causative organism should be classified. Recent news agency and social media reports of an increase in the "flesh-eating infection donovanosis" have been false and unhelpful, only leading to hyperbole and increased stigma among those infected. Donovanosis is a progressive, mildly infectious bacterial infection usually involving the genital area. The causative organism is a gram-negative bacillus, Calymmatobacterium granulomatis. A proposal that the organism be reclassified as Klebsiella granulomatis comb nov was put forward in 1999; however, a consensus is yet to be reached about the definitive nomenclature of the causative agent.1.

The first truly terrestrial apex predators were carnivorous synapsids, which emerged in the Permian over 260 million years ago and evolved against a backdrop of harsh ecological change. In many ways, these predators mirrored feeding modes and evolutionary trends seen in their much later descendants, the flesh-eating mammals; could apparent resemblances indicate evolutionary constraints on form, or were they shaped by natural selection? Here we show that the skulls of carnivorous Permian synapsids were shaped primarily by adaptation, their shapes reflecting trophic function, and with similarities between distant relatives arising by convergence through natural selection. Conversely, we find no evidence for constraint in terms of the direction or rate of evolution based on patterns of topological modularity. These findings illustrate methods of identifying evolutionary processes in deep time and emphasise the role of competition and adaptation over intrinsic constraints in macroevolution.

The evolutionary transition to parasitism in the family Calliphoridae serves as a compelling model to study the genetic and molecular basis of ecological adaptations. In this study, we sequenced and annotated the genomes of Chrysomya megacephala, Chrysomya putoria, and Lucilia eximia to provide a foundation to investigate the evolution of coding and non-coding sequences within the family Calliphoridae. Combining these new resources with publicly available genomes from 11 representatives of the family, we focused on two species with distinct parasitic strategies, Cochliomyia hominivorax -a flesh-eating parasite-, and Protophormia azurea -a blood-feeding parasite- to identify unique and shared genomic features associated with the evolution of the parasitic lifestyle. Comparative analyses of conserved non-exonic elements revealed 44 genes inferred to convergently evolve at an accelerated evolutionary rate, 41 % of which associate with development, highlighting their potential role in larval feeding specialization. Analyses of coding regions identified genes, including those linked to olfaction, taste, chitin and cuticle formation, inferred to evolve at accelerated rates in both Co. hominivorax and P. azurea. This study advances our understanding of aspects of the evolution of genomic regions of members of the family under natural selection and their potential contribution to parasitism.

Collagen, the major structural protein in the animal extracellular matrix, forms a triple helix that resists proteolysis and requires specialised enzymes for degradation. Flesh-eating bacteria secrete collagenases that unwind the collagen triple helix and processively trim Gly-X-Y triplet repeats, yet the molecular basis of this process has remained obscure. Here, cryo-electron microscopy reveals how Hathewaya histolytica collagenase ColH engages its substrate and exploits the helix's architecture for catalysis. ColH encircles a single collagen triple helix in a closed-ring conformation and, through dynamic domain motions, dehydrates and destabilises it. The enzyme undergoes substrate-assisted twisting to adopt a rigid ratcheted conformation, in which one chain is bent into a tripeptide-long 'bight' and threaded into the active site for cleavage, while two uncut strands are partitioned to non-catalytic sites. Release of the bight appears to reset the enzyme, with the uncut strands serving as guiding tracks. Repeated cycling between dynamic and rigid states likely enables triplet-by-triplet translocation, allowing ColH to harness collagen's geometry for processive degradation. These findings reveal a bacterial strategy for collagen unwinding and cleavage distinct from that of mammalian collagenases, highlighting divergent evolutionary solutions for degrading one of nature's most intractable substrates.

Necrotising fasciitis, commonly referred to as "flesh-eating disease," is a rapidly spreading soft tissue infection characterised by extensive necrosis of the skin, subcutaneous tissue, and fascia while sparing the underlying muscle. Despite its low overall incidence, it is a significant soft tissue infection due to its rapid spread and associated high mortality risk. This prospective pilot study aims to analyse 25 consecutive cases of necrotising fasciitis to assess various aspects, including age and sex incidence, microbial flora, role of co-morbidities in prognosis, and overall outcome. We conducted a descriptive study involving 25 patients aged 18-84 years diagnosed with necrotising fasciitis over a 6-month period (January 2022 to June 2022) at Saveetha Medical College. Of the 25 patients treated, 21 (84%) were male and 4 (21%) were female, resulting in a male-to-female ratio of 5.25. The age ranged from 18 to 84 years (Mean age: 50.24 ± Standard deviation, SD=14.175). Trauma was identified as the main precipitating factor in approximately 40% of cases, while Diabetes Mellitus (40%) emerged as the most common co-morbidity. Lower limb involvement was predominant in both male and female patients. The infection was monomicrobial in 32% of cases (Enterococci 16% + Bacteroides 16%) and poly-microbial in 68% with Streptococcus pyogenes + Escherichia coli being the most common organism combination. Wound debridement followed by split skin graft was the most common treatment modality (84%), with the number of debridement sessions varying based on infection severity (corresponding with higher LRINEC scores). Prolonged hospital stay was the most common complication, observed in 52% of cases. Our analysis revealed that necrotising fasciitis is more prevalent in individuals aged over 50 years with a male predominance. Streptococcus pyogenes with Escherichia coli was the predominant microflora, and Diabetes Mellitus emerged as the most common comorbidity. Early recognition, prompt control of diabetes mellitus, aggressive surgical treatment, and supportive therapy are essential steps in managing necrotising fasciitis.

In recent years, particularly since the outbreaks of scarlet fever and invasive group A streptococcal diseases/infections (iGAS) in several European countries in 2022, iGAS has garnered widespread attention. Recently, Japan experienced an outbreak of a specific type of iGAS, streptococcal toxic shock syndrome (STSS). The outbreak was reported under the label"flesh-eating bacteria,"emphasizing the pathogenic potential of group A streptococcus (GAS). Although GAS is not a newly emerging pathogen and remains susceptible to antibiotics, and guidelines exist for the diagnosis and treatment of various clinical manifestations of iGAS, systematic surveillance and research on iGAS are lacking in China. The high mortality rate associated with the STSS outbreak in Japan highlights the need for continued attention to GAS-related diseases, with a focus on emerging trends in iGAS epidemiology, as well as changes in bacterial virulence and transmission dynamics. There is a pressing need to conduct research based on domestic clinical practice to enhance iGAS diagnosis, treatment, and prevention, ultimately to safeguard public health. 近二三十年，尤其自2022年欧洲多国暴发猩红热和侵袭性A族链球菌疾病/感染（iGAS）疫情以来，iGAS引起了广泛关注。近期日本暴发了iGAS特殊类型——链球菌中毒性休克综合征（STSS）疫情，当局以“食人菌”的名称报道疫情，突显了GAS的致病威力。GAS并非新发病原，且有敏感抗菌药物，各种iGAS临床类型的诊断和治疗也有规范可循。但是，我国对iGAS缺乏系统监测和研究。日本STSS疫情及其较高的致死率警示我们仍需重视GAS疾病，关注iGAS流行病学新变化，以及菌株致病性和传播能力等改变，结合国内临床实践积极开展相关研究，提高iGAS临床诊治和防控水平，保障人民健康。.

Necrotizing soft tissue infections (NSTIs) are characterized by "flesh-eating bacteria" that are rapidly progressive and require immediate diagnosis and aggressive surgical debridement along with broad-spectrum antibiotics. Common pathogens, such as Streptococcus pyogenes, Staphylococcus aureus, Enterococcus coli, and Clostridium, are the usual culprits of this disease. While NSTIs have a relatively low incidence, they are associated with higher rates of morbidity and mortality. Due to the aggressive nature of the pathogen, NSTI can cause widespread necrosis of soft tissue and muscle, leading to extensive surgical intervention and patient disfigurement. The patient population that is most susceptible to NSTI includes the elderly, immunocompromised, and diabetics. In this case report, the patient is a 54-year-old woman with a past medical history of type 2 diabetes mellitus, hepatitis C, and an extensive spinal surgery with malfunctioning spinal hardware who developed an NSTI while in the intensive care unit.

Necrotising soft tissue infections (NSTI) are life-threatening conditions caused by diverse bacteria. Treatment strategies have remained largely universal and unchanged, and only modest improvements in patient outcomes have been observed. Emerging insights into NSTI pathogenesis may enable more targeted approaches. Because microbial aetiology is central to guiding appropriate therapy, we aimed to develop and externally validate machine learning models capable of predicting microbial aetiology using only data available at an early stage. In parallel, we explored whether similar models could predict selected clinical endpoints related to surgical management, patient handling, and organ support. We used data from the INFECT study, an international multicentre prospective cohort investigating NSTI characteristics and pathogenesis. A total of 409 adults with surgically confirmed NSTI were enrolled between February 2013 and June 2017 from five Scandinavian hospitals. More than 700 clinical variables were collected from hospital admission to intensive care unit entry. Machine learning models were developed to predict the presence of Streptococcus pyogenes (GAS, Group A streptococcus) and five clinical endpoints: risk of amputation, size of skin defect, maximum skin defect size, length of intensive care (ICU) stay, and need for renal replacement therapy. Unsupervised variable selection was implemented, and Shapley Additive explanations were used for model interpretability. External validation employed a retrospective multicentre cohort of 216 NSTI patients treated in 11 Dutch hospitals between January 2013 and December 2017. Eight presurgical variables (age, diabetes, affected area, prior surgical intervention, and blood creatinine and haemoglobin concentrations) were sufficient for predicting GAS aetiology with high discriminatory power. Performance was good in both the development cohort (ROC-AUC 0.828; 95% CI 0.763-0.883) and the external validation cohort (ROC-AUC 0.758; 95% CI 0.696-0.821). Prediction of clinical endpoints related to surgical management, ICU stay, and organ support was unsuccessful. We developed and externally validated a model predicting GAS aetiology in NSTI using presurgical data alone. Early identification of GAS may improve clinical handling and support tailored decisions on treatment and infection control, including management of close contacts and reduction of hospital transmission risk.

It has been argued that Homo habilis was responsible for the earliest episodes of stone-tool making, animal butchery, meat eating, and the reversal of the predator-prey relationship with carnivores. Assessing the empirical foundation of these premises is of utmost relevance to understanding the role that H. habilis played in our evolution. A powerful position for H. habilis, regarding carnivore-hominin interactions, requires that this hominin could cope with predation hazards. This should be reflected in bones of H. habilis impacted by scavengers instead of flesh-eating predators. Determining carnivore taxon-specific agency on the modification of hominin bones is crucial for solving this dichotomy. Artificial intelligence (AI) tools, through computer vision (CV) methods, have proven successful at differentiating carnivore taxa using images of bone surface modifications (BSMs). The application of CV methods to the remains of the holotype and other specimens of H. habilis documents with unprecedented reliability that Olduvai Hominin (OH) 7 and OH 65 were consumed by leopards. This has consequences for our understanding of the role played by H. habilis on the emergence of the Oldowan archeological record, and of the evolution of behaviors that led to a fully terrestrial adaptation and a shift in the balance of power between carnivorans and hominins.

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drug called Xylazine has gained notoriety in recent times, earning the nickname "zombie drug" due to reported alarming effects on its users. Although Xylazine is primarily intended for veterinary use as a sedative and muscle relaxant for animals, there have been growing concerns about its misuse among humans, particularly in the context of illicit drug use. However, it is essential to rely on accurate and evidence-based information when discussing the health risks associated with any substance, rather than resorting to sensationalized terms like "zombie drug." The situation involving Xylazine misuse is a matter of concern, and the United States Drug Enforcement Administration has highlighted it as a significant threat to public health.

Background: Vibrio, a group of Gram‑negative bacteria found in the ocean, has become a significant global threat, intensified by climate change, owing to its crucial roles in environmental, human, and animal health. Research on these bacteria and the diseases they cause has greatly influenced scientific progress, resulting in major advancements in the fields of microbiology, epidemiology, and public health. Objectives: This review aims to highlight the early groundbreaking discoveries in Vibrio research, particularly those that have significantly impacted the science of microbiology and global health. Methods: A comprehensive literature search was conducted across vast databases of biomedical and life sciences literature including PubMed, EMBASE, and Scopus. Additionally, a search of the grey literature was performed. Studies that marked early groundbreaking discoveries in Vibrio research, with wide implications for human society, were included. Findings and conclusion: Research on Vibrio has led to major advancements in our understanding of disease mechanisms, pathogen ecology, and the epidemiology of waterborne infections. A landmark discovery was the identification of Vibrio cholerae in 1884, which played a crucial role in studying waterborne diseases such as cholera and led to the development of modern approaches to treat diarrheal diseases, such as the introduction of oral rehydration salt (ORS) therapy. Certain Vibrio strains, such as Vibrio vulnificus, are important models for studying flesh‑eating diseases, while others, such as Vibrio parahaemolyticus ST3, ST36, and V. cholerae O1, are the only marine bacteria known to cause global epidemics by spreading across continents. Key mechanisms in Gram‑negative bacteria, including the viable but nonculturable (VBNC) state, quorum sensing, and the type VI secretion system (T6SS), were first discovered in Vibrio species. Today, research on Vibrio bacteria remains crucial from a global health perspective, especially owing to the expanding effects of climate change on their worldwide distribution.

Necrotising fasciitis (NF), commonly referred to as 'flesh-eating disease', is a rare but life-threatening infection. It rapidly affects subcutaneous tissue, leading to necrosis of the overlying skin. Though primarily seen in the abdomen, perineum and lower limbs, periorbital involvement is rare. This case report presents an elderly male with periorbital NF following a minor head injury. The patient presented with bilateral periorbital swelling, purulent discharge and necrotic tissue. Microbiological analysis revealed a rare Enterococcus species as the causative pathogen. MRI and microbiological analysis confirmed the diagnosis. Treatment included intravenous antibiotics, surgical debridement and skin grafting. The patient showed significant improvement post-treatment. This case underscores the importance of prompt diagnosis and treatment to prevent severe complications.

The inflammatory cytokine response is essential for protective immunity, yet bacterial and viral pathogens often elicit an exaggerated response ("cytokine storm") harmful to the host that can cause multi-organ damage and lethality. Much has been published recently on the cytokine storm within the context of the coronavirus pandemic, yet bacterial sepsis, severe wound infections and toxic shock provide other prominent examples. The problem of the cytokine storm is compounded by the increasing incidence of multidrug-resistant bacterial strains. We created an incisive molecular tool for analyzing the role of the B7/CD28 costimulatory axis in the human inflammatory response. To attenuate the cytokine storm underlying infection pathology, yet preserve host defenses, we uniquely targeted the engagement of CD28 with its B7 co-ligands by means of short peptide mimetics of the human CD28 and B7 receptor homodimer interfaces. These peptides are not only effective tools for dissecting mechanism but also serve to attenuate the inflammatory response as a broad host-oriented therapeutic strategy against the cytokine storm. Indeed, such peptides protect mice from lethal Gram-positive bacterial superantigen-induced toxic shock even when dosed in molar amounts well below that of the superantigen and show promise in protecting humans from the severe inflammatory disease necrotizing soft tissue infections ('flesh-eating' bacterial sepsis) following traumatic wound injuries.