Granulicatella species,previously classified as nutritionally variant streptococci,have emerged as important opportunistic pathogens.Although typically part of the normal oral,gastrointestinal,and genitourinary flora,...Granulicatella species,previously classified as nutritionally variant streptococci,have emerged as important opportunistic pathogens.Although typically part of the normal oral,gastrointestinal,and genitourinary flora,these fastidious Gram-positive cocci can cause serious infections in both immunocompetent and immunocompromised individuals.Their identification often proves difficult due to slow growth and unusual nutritional requirements,which limit the reliability of conventional culture methods.This narrative review consolidates data from over 100 case reports and clinical studies to present a comprehensive overview of Granulicatella infections.Infective endocarditis appears as the most frequently reported and life-threatening condition,often affecting the aortic and mitral valves.Patients with prosthetic valves or congenital heart defects face a higher risk.Delayed diagnosis frequently results in complications such as heart failure,systemic emboli,and renal dysfunction.Granulicatella species also contribute to osteomyelitis,pulmonary infections,brain abscesses,gastrointestinal sepsis,and infections related to implanted medical devices.Effective management typically involves beta-lactam antibiotics combined with aminoglycosides,although antimicrobial resistance remains a concern.Surgical intervention often proves necessary,especially in cases with prosthetic material or severe complications.Outcomes are generally favorable when infections are identified early and managed effectively.However,delayed recognition and suboptimal therapy continue to contribute to poor prognoses in some patients.This review emphasizes the need to improve clinical awareness and establish standardized diagnostic and therapeutic approaches to address the challenges posed by Granulicatella infections.展开更多
The effects of O3/Cl2 disinfection on corrosion and the growth of opportunistic pathogens in drinking water distribution systems were studied using annular reactors （ARs）. The corrosion process and most probable num...The effects of O3/Cl2 disinfection on corrosion and the growth of opportunistic pathogens in drinking water distribution systems were studied using annular reactors （ARs）. The corrosion process and most probable number （MPN） analysis indicated that the higher content of iron-oxidizing bacteria and iron-reducing bacteria in biofilms of the AR treated with O3/Cl2 induced higher Fe304 formation in corrosion scales. These corrosion scales became more stable than the ones that formed in the AR treated with Cl2 alone. O3/Cl2 disinfection inhibited corrosion and iron release efficiently by changing the content of corrosion-related bacteria. Moreover, ozone disinfection inactivated or damaged the opportunistic pathogens due to its strong oxidizing properties. The damaged bacteria resulting from initial ozone treatment were inactivated by the subsequent chlorine disinfection. Compared with the AR treated with Cl2 alone, the opportunistic pathogens M. auium and L. pneumophila were not detectable in effluents of the AR treated with O3/Cl2, and decreased to （4.60 ± 0.14） and （3.09 ± 0.12） loglo （gene copies/g corrosion scales） in biofilms, respectively. The amoeba counts were also lower in the AR treated with O3/Cl2. Therefore, O3/Cl2 disinfection can effectively control opportunistic pathogens in effluents and biofilms of an AR used as a model for a drinking water distribution system.展开更多
Objective Our objective was to investigate the occurrence of opportunistic pathogens and characterize the bacterial community structures in the water system of a pulmonary hospital.Methods The water samples were colle...Objective Our objective was to investigate the occurrence of opportunistic pathogens and characterize the bacterial community structures in the water system of a pulmonary hospital.Methods The water samples were collected from automatic and manual faucets in the consulting room,treatment room,dressing room,respiratory ward,and other non-medical rooms in three buildings of the hospital.Quantitative polymerase chain reaction was used to quantify the load of several waterborne opportunistic pathogens and related microorganisms,including Legionella spp.,Mycobacterium spp.,and M.avium.Illumina sequencing targeting 16 S r RNA genes was performed to profile bacterial communities.Results The occurrence rates of Legionella spp.,Mycobacterium spp.,and M.avium were 100%,100%,and 76%,respectively in all samples.Higher occurrence rates of M.avium were observed in the outpatient service building(building 1,91.7%)and respiration department and wards(building 2,80%)than in the office building(building 3),where no M.avium was found.M.avium were more abundant in automatic faucets(average 2.21×10~4 gene copies/L)than in manual faucets(average 1.03×10~4 gene copies/m L)(P<0.01).Proteobacteria,Actinobacteria,Bacteroidetes,Cyanobacteria,Firmicutes,and Acidobacteria were the dominant bacterial phyla.Disinfectant residuals,nitrate,and temperature were found to be the key environmental factors driving microbial community structure shifts in water systems.Conclusion This study revealed a high level of colonization of water faucets by opportunistic pathogens and provided insight into the characteristics of microbial communities in a hospital water system and approaches to reduce risks of microbial contamination.展开更多
Many problems in drinking water distribution systems(DWDSs)are caused by microbe,such as biofilm formation,biocorrosion and opportunistic pathogens growth.More iron release from corrosion scales may induce red water.B...Many problems in drinking water distribution systems(DWDSs)are caused by microbe,such as biofilm formation,biocorrosion and opportunistic pathogens growth.More iron release from corrosion scales may induce red water.Biofilm played great roles on the corrosion.The iron-oxidizing bacteria(IOB)promoted corrosion.However,when iron-reducing bacteria(IRB)and nitrate-reducing bacteria(NRB)became the main bacteria in biofilm,they could induce iron redox cycling in corrosion process.This process enhanced the precipitation of iron oxides and formation of more Fe3 O4 in corrosion scales,which inhibited corrosion effectively.Therefore,the IRB and NRB in the biofilm can reduce iron release and red water occurrence.Moreover,there are many opportunistic pathogens in biofilm of DWDSs.The opportunistic pathogens growth in DWDSs related to the bacterial community changes due to the effects of micropollutants.Micropollutants increased the number of bacteria with antibiotic resistance genes(ARGs).Furthermore,extracellular polymeric substances(EPS)production was increased by the antibiotic resistant bacteria,leading to greater bacterial aggregation and adsorption,increasing the chlorine-resistance capability,which was responsible for the enhancement of the particle-associated opportunistic pathogens in DWDSs.Moreover,O3-biological activated carbon filtration-UV-Cl2 treatment could be used to control the iron release,red water occurrence and opportunistic pathogens growth in DWDSs.展开更多
Burkholderia cepacia （Bc） and Pseudomonas aeruginosa （Pa） are both biocontrol agents in agriculture and opportunistic human pathogens in hospitals. Effective management and utilization practice is needed to unders...Burkholderia cepacia （Bc） and Pseudomonas aeruginosa （Pa） are both biocontrol agents in agriculture and opportunistic human pathogens in hospitals. Effective management and utilization practice is needed to understand their characteristics and distribution in rice. During the last decade, the two opportunistic human pathogens were detected in 631 samples of rice seed and 117 samples of rice plant in plain, highland and mountainous rice growing areas of China. Bc and Pa were primarily differentiated by common bacteriological characteristics and pathogenic tests and then identified into species by Biolog and FAME tests. However, the genotypes of Bc still could not be distinguished. It has been noted that the Bc and Pa mainly existed in rice root with the highest distribution frequency in plain areas （ 6.1% and 16.1%） and lowest in the mountainous areas （1.0% and 7.8%）.展开更多
White-nose syndrome(WNS)has caused recent catastrophic declines among multiple species of bats in eastern North America.The disease's name derives from a visually apparent white growth of the newly discovered fung...White-nose syndrome(WNS)has caused recent catastrophic declines among multiple species of bats in eastern North America.The disease's name derives from a visually apparent white growth of the newly discovered fungus Geomyces destructans on the skin(including the muzzle)of hibernating bats.Colonization of skin by this fungus is associated with characteristic cutaneous lesions that are the only consistent pathological finding related to WNS.However,the role of G.destructans in WNS remains controversial because evidence to implicate the fungus as the primary cause of this disease is lacking.The debate is fuelled,in part,by the assumption that fungal infections in mammals are most commonly associated with immune system dysfunction.Additionally,the recent discovery that G.destructans commonly colonizes the skin of bats of Europe,where no unusual bat mortality events have been reported,has generated further speculation that the fungus is an opportunistic pathogen and that other unidentified factors are the primary cause of WNS.展开更多
The dissemination of antibiotic resistance genes(ARGs)has emerged as a global public health concern.However,the distribution and driving factors of ARGs,especially high-risk ARGs,in the fish gut from natural water eco...The dissemination of antibiotic resistance genes(ARGs)has emerged as a global public health concern.However,the distribution and driving factors of ARGs,especially high-risk ARGs,in the fish gut from natural water eco-systems remain largely unclear.In the present study,high-throughput quantitative PCR(HT-qPCR)and 16S rRNA gene sequencing were deployed to determine the ARG profiles and microbial communities in the fish gut across 13 sampling sites from the Xiangjiang River,one of the major tributaries of the Yangtze River in China.In total,120 ARG subtypes were identified,dominated by macrolide-lincosamide-streptogramin B(MLSB)resis-tance genes.The abundance of ARGs varied across sampling sites,with highest at Xiangxiang(XX)and lowest at Chaling(CL).Furthermore,it was observed that ARG abundance was higher in the tributaries compared to the trunk stream,with an increasing trend from upstream to downstream.At the ranks of phylum and genus,the fish gut microbiota was predominantly composed of Proteobacteria and Escherichia,respectively.Several opportu-nistic pathogens(Vibrio,Streptococcus,and Pseudomonas)exhibited significantly positive correlations with high-risk ARGs(floR,emrB,and ermD).Finally,the assembly of ARGs in the Xiangjiang River was dominated by deterministic processes and significantly influenced by mobile genetic elements(MGEs),environmental factors,heavy metals,and geographic location.Overall,the findings of this study illustrate the prevalence of ARGs and opportunistic pathogens in the fish gut within the Xiangjiang River,highlighting potential risks to public health.These results provide valuable insights for developing targeted strategies to manage and assess ARGs in natural water ecosystems.展开更多
Acinetobacter(A.)baumannii is a Gram-negative,non-fermenting opportunistic pathogen increasingly implicated in nosocomial infections,particularly in intensive care units(ICUs).Its ability to acquire multidrug resistan...Acinetobacter(A.)baumannii is a Gram-negative,non-fermenting opportunistic pathogen increasingly implicated in nosocomial infections,particularly in intensive care units(ICUs).Its ability to acquire multidrug resistance(MDR),including to carbapenems,poses a major public health threat.Infections caused by A.baumannii-ranging from pneumonia to bloodstream and wound infections-are difficult to treat and associated with high mortality,especially in critically ill patients[1].展开更多
Rhodococcus equi, previously known as Corynebacterium equi, is one of the most important causes of zoonotic infections in grazing animals. Increased cases of human infection with R. equi have been reported, especially...Rhodococcus equi, previously known as Corynebacterium equi, is one of the most important causes of zoonotic infections in grazing animals. Increased cases of human infection with R. equi have been reported, especially in immunocompromised patients, within recent years. We present a case of R. equi bacteremia in a 51-year-old man with diabetes and liver cirrhosis, on long-term corticosteroid therapy after skin-grafting surgery. The patient recovered soon after he was treated with vancomycin. This review focuses on the microbiological characteristics of this organism, and the diagnosis and treatment of this infection.展开更多
This study profiled the bacterial community variations of water from four water treatment systems,including coagulation,sedimentation,sand filtration,ozonation-biological activated carbon filtration(O3-BAC),disinfecti...This study profiled the bacterial community variations of water from four water treatment systems,including coagulation,sedimentation,sand filtration,ozonation-biological activated carbon filtration(O3-BAC),disinfection,and the tap water after the distribution process in eastern China.The results showed that different water treatment processes affected the bacterial community structure in different ways.The traditional treatment processes,including coagulation,sedimentation and sand filtration,reduced the total bacterial count,while they had little effect on the bacterial community structure in the treated water(before disinfection).Compared to the traditional treatment process,O3-BAC reduced the relative abundance of Sphingomonas in the finished water.In addition,ozonation may play a role in reducing the relative abundance of Mycobacterium.NaClO and ClO2 had different effects on the bacterial community in the finished water.The relative abundance of some bacteria(e.g.Flavobacterium,Phreatobacter and Porphyrobacter)increased in the finished water after ClO2 disinfection.The relative abundance of Mycobacterium and Legionella,which have been widely reported as waterborne opportunistic pathogens,increased after NaClO disinfection.In addition,some microorganisms proliferated and grew in the distribution system,which could lead to turbidity increases in the tap water.Compared to those in the finished water,the relative abundance of Sphingomonas,Hyphomicrobium,Phreatobacter,Rheinheimera,Pseudomonas and Acinetobacter increased in the tap water disinfected with NaClO,while the relative abundance of Mycobacterium increased in the tap water disinfected with ClO2.Overall,this study provided the detailed variation in the bacterial community in the drinking water system.展开更多
Anthropogenic stressors can favor the occurrence of noninfectious disease that can be worsened by the impact of opportunistic pathogens,making the epizootiology of environmental diseases difficult to unravel.The incid...Anthropogenic stressors can favor the occurrence of noninfectious disease that can be worsened by the impact of opportunistic pathogens,making the epizootiology of environmental diseases difficult to unravel.The incidence and impact of oral lesions in nestlings of a facultative scavenger species,the black kite Milvus migrans,were examined over seven breeding seasons in the highly degraded environment close to Madrid,Spain.We found an overall prevalence of 31%of nestlings with oral lesions,with no clear spatial pattern in nests with affected and unaffected individuals.The occurrence and number of oral lesions were negatively associated with nestling body condition and brood size.Broods,where all siblings had oral lesions,were smaller than those where some or all siblings were apparently healthy,suggesting that oral disease could be causing nestling mortality and,consequently,brood size reduction.In turn,nestling body condition was negatively affected by lesion occurrence,brood size,and laying date.Although these relationships were bidirectional,piecewise structural equation modeling analyses showed a greater negative effect of body condition on lesion occurrence than vice versa,indicating that nestlings in poorer body condition were more likely to develop oral lesions(which could contribute to aggravate their state of deterioration)than those in better condition.Nestlings from small broods were also more likely to have oral disease(directly or indirectly through their lower body condition)than nestlings from large broods.Nestlings that hatched last in the broods showed greater development stress than those that hatched first.Anthropogenic stressors could trigger poor body condition,and contribute to microbiota dysbiosis-related diseases.Although further research is needed to determine the consequences for the long-term fitness of individuals,actions should be taken to mitigate adverse conditions that may favor the appearance of environmental diseases associatedwithperi-urbanareas,giventheirrapidexpansion overnatural areas.展开更多
Postoperative infection is a major global health concern,affecting 5%-10%of surgical patients and nearly doubling mortality in severe cases[1].Transplant recipients are particularly vulnerable,with 30%-80%developing i...Postoperative infection is a major global health concern,affecting 5%-10%of surgical patients and nearly doubling mortality in severe cases[1].Transplant recipients are particularly vulnerable,with 30%-80%developing infections within 30 days,often from opportunistic pathogens[2,3].Key risk factors include epidemiological exposure,net immunosuppression,age,transplant type,and surgical history[4].Despite known infection risks,current evidence remains transplantation type-specific and neglects behavioral modulators[5].Different types of transplantation may share similar risk factors[6].To identify common factors affecting postoperative infection,this study collected standardized clinical data-including diet,psychological response,medication use,and biochemical indicators-from liver and kidney transplant patients across six hospitals using a unified standard operating procedure(SOP).展开更多
To the Editor:Klebsiella pneumoniae(K.pneumoniae)is a common opportunistic pathogen with rising prevalence in clinical settings.A multicenter study reported its detection rate among hospitalized adults with community-...To the Editor:Klebsiella pneumoniae(K.pneumoniae)is a common opportunistic pathogen with rising prevalence in clinical settings.A multicenter study reported its detection rate among hospitalized adults with community-acquired pneumonia(CAP)has increased annually,making it the leading cause of severe CAP(SCAP),surpassing Streptococcus pneumoniae.[1]Hypervirulent K.pneumoniae(hvKP),especially sequence type(ST)23,[2]exhibits enhanced virulence and colonization,driven by multiple siderophore systems and virulence plasmids,and is linked to high mortality.[3]Alarmingly,tigecycline resistance in ST23 strains is increasing.While tigecycline is crucial for treating multidrug-resistant and carbapenem-resistant K.pneumoniae,resistance—mainly due to efflux pump overexpression,enzymatic inactivation,and target site mutations—has been widely reported.[4]Mutations in regulators such as RamR(a TetR-family transcriptional repressor regulating ramA)are involved,[5]but their roles in hvKP remain unclear.In this study,a novel RamR point mutation was identified and validated via whole-genome sequencing,gene editing,quantitative real-time polymerase chain reaction(qRT-PCR),proteomics,and electrophoretic mobility shift assay(EMSA).This mutation reduced ramA repression,resulting in efflux pump overexpression,and conferred tigecycline resistance.The Medical Ethics Committee of Qingdao Municipal Hospital approved this study(No.XM:2023-030).展开更多
To the Editor:Klebsiella pneumoniae(KP)is a common opportunistic pathogen causing potentially life-threatening illness and organ failure.Surveillance data from the 2023 China Antimicrobial Surveillance Network(CHINET)...To the Editor:Klebsiella pneumoniae(KP)is a common opportunistic pathogen causing potentially life-threatening illness and organ failure.Surveillance data from the 2023 China Antimicrobial Surveillance Network(CHINET)revealed that the KP isolation rate from clinical respiratory specimens in China was the highest(18.1%)among all bacteria.[1]Both classical(cKP)and hypervirulent KP(hvKP)exert significant effects on the systemic inflammatory response,causing infection-related anemia and high mortality to host.The main gap in current research is that the specific virulence factors of KP that cause host infectious anemia have not been identified.展开更多
Urban life has led to the creation of human-made environments that,from a microbiological perspective,provide extreme life conditions.Certain non-ubiquitous microorganisms such as thermophilic members of the black yea...Urban life has led to the creation of human-made environments that,from a microbiological perspective,provide extreme life conditions.Certain non-ubiquitous microorganisms such as thermophilic members of the black yeast genus Exophiala are enriched within these habitats for which no counterpart is known in nature.Dishwashers consistently accumulate a number of specific black,white and red yeasts on the rubber seals of doors and in stagnant water at the interior.Several of these yeasts are primarily known as agents of human opportunistic infections.In this review,the literature data are supported by a screening study involving 937 households in 15 cities in Turkey.Fungi were detected in 230 samples(24.5%).Using rDNA sequencing,the prevalent species were identified as Exophiala dermatitidis(n=116),Candida parapsilosis(n=44),E.phaeomuriformis(n=35),Magnusiomyces capitatus(n=22),Rhodotorula mucilaginosa(n=15),and C.lusitaniae(n=14).The possible role of dishwashers in transmitting disease is discussed.展开更多
What is already known about this topic?Enterococcus spp.,while naturally occurring as commensal bacteria in the gastrointestinal tract of animals and humans,have emerged as significant opportunistic pathogens in healt...What is already known about this topic?Enterococcus spp.,while naturally occurring as commensal bacteria in the gastrointestinal tract of animals and humans,have emerged as significant opportunistic pathogens in healthcare settings.What is added by this report?A comprehensive surveillance study revealed enterococci in 14.39%of clinical samples from dogs and cats across China during 2018–2021.Multidrugresistant enterococcal infections showed significant correlation with urinary tract catheterization and extended hospitalization periods.Notably,pet-derived Enterococcus faecalis isolates demonstrated high genetic similarity with strains isolated from humans,farm animals,and environmental sources.What are the implications for public health practice?These findings underscore the critical need for enhanced surveillance of enterococcal infections and implementation of stringent aseptic protocols in veterinary clinical settings.Particular attention should be directed toward linezolid-resistant Enterococcus faecalis infections due to their demonstrated potential for transmission between pets and humans.展开更多
Dear Editor,In the intestine of humans and other animals,the commensal microbiome has complex roles in shaping infections(Khan et al.,2021).Commensal microbiome contains opportunistic pathogens that are usually suppre...Dear Editor,In the intestine of humans and other animals,the commensal microbiome has complex roles in shaping infections(Khan et al.,2021).Commensal microbiome contains opportunistic pathogens that are usually suppressed but can cause infection under microbiome dysbiosis or environmental disturbances(Dey and Ray Chaudhuri,2023).展开更多
Prototheca wickerhamii,an opportunistic pathogen affecting both humans and animals,is widely distributed in the environment,including soil,mud,and water sources such as rivers.However,human infections caused by this g...Prototheca wickerhamii,an opportunistic pathogen affecting both humans and animals,is widely distributed in the environment,including soil,mud,and water sources such as rivers.However,human infections caused by this genus are rare[1].Unfortunately,due to the nonspecific clinical manifestations and limited awareness among clinicians,protothecosis is often underestimated and misdiagnosed.P.wickerhamii has been shown to exhibit low cytotoxicity tomacrophages,potentially allowing it to evade immune clearance[2].Currently,the highquality genome sequencing technology offers insights into the evolution and pathogenicity of Prototheca while also serving as a genomic resource for improved diagnosis[3].展开更多
The genus Aeromonas is considered as indigenous prokaryote to aquatic environments. These genus members are capable of colonizing in water bodies such as potable water, sewage and sea water. Aeromonas sp. is the most ...The genus Aeromonas is considered as indigenous prokaryote to aquatic environments. These genus members are capable of colonizing in water bodies such as potable water, sewage and sea water. Aeromonas sp. is the most significant opportunistic pathogen in humans with the potential to cause different kinds of infections in blood, tissues, intestine, and dermis. The leading pathogenic species includes Aeromonas hydrophila, A. caviae and A. veronii. The ubiquitous nature in the environment associated with the virulence of these bacteria has been reported. Evidence for the waterborne transmission to humans by Aeromonas sp. is also documented. The Aeromonas found in wastewater and its impact on marine environment is hardly discussed and its bibliography is lacking. The aim of this research was to identify the major biomarker genes in Aeromonas sp., and it's in silico sequence analysis.展开更多
Candida albicans is an opportunistic fungal pathogen of humans.It causes a variety of infections ranging from superficial mucocutaneous conditions to severe systemic diseases that result in substantial morbidity and m...Candida albicans is an opportunistic fungal pathogen of humans.It causes a variety of infections ranging from superficial mucocutaneous conditions to severe systemic diseases that result in substantial morbidity and mortality.This pathogen frequently forms biofilms resistant to antifungal drugs and the host immune system,leading to treatment failures.Recent research has demonstrated the potential of nanorobots to penetrate biological barriers and disrupt fungal biofilms.In this perspective paper,we provide a brief overview of recent breakthroughs in nanorobots for candidiasis treatment and discuss current challenges and prospects.展开更多
文摘Granulicatella species,previously classified as nutritionally variant streptococci,have emerged as important opportunistic pathogens.Although typically part of the normal oral,gastrointestinal,and genitourinary flora,these fastidious Gram-positive cocci can cause serious infections in both immunocompetent and immunocompromised individuals.Their identification often proves difficult due to slow growth and unusual nutritional requirements,which limit the reliability of conventional culture methods.This narrative review consolidates data from over 100 case reports and clinical studies to present a comprehensive overview of Granulicatella infections.Infective endocarditis appears as the most frequently reported and life-threatening condition,often affecting the aortic and mitral valves.Patients with prosthetic valves or congenital heart defects face a higher risk.Delayed diagnosis frequently results in complications such as heart failure,systemic emboli,and renal dysfunction.Granulicatella species also contribute to osteomyelitis,pulmonary infections,brain abscesses,gastrointestinal sepsis,and infections related to implanted medical devices.Effective management typically involves beta-lactam antibiotics combined with aminoglycosides,although antimicrobial resistance remains a concern.Surgical intervention often proves necessary,especially in cases with prosthetic material or severe complications.Outcomes are generally favorable when infections are identified early and managed effectively.However,delayed recognition and suboptimal therapy continue to contribute to poor prognoses in some patients.This review emphasizes the need to improve clinical awareness and establish standardized diagnostic and therapeutic approaches to address the challenges posed by Granulicatella infections.
基金supported by the National Natural Science Foundation of China(No.51290281)the project of Chinese Academy of Sciences(No.QYZDY-SSW-DQC004)the Federal Department of Chinese Water Control and Treatment(Nos.2017ZX07108,2017ZX07501002)
文摘The effects of O3/Cl2 disinfection on corrosion and the growth of opportunistic pathogens in drinking water distribution systems were studied using annular reactors （ARs）. The corrosion process and most probable number （MPN） analysis indicated that the higher content of iron-oxidizing bacteria and iron-reducing bacteria in biofilms of the AR treated with O3/Cl2 induced higher Fe304 formation in corrosion scales. These corrosion scales became more stable than the ones that formed in the AR treated with Cl2 alone. O3/Cl2 disinfection inhibited corrosion and iron release efficiently by changing the content of corrosion-related bacteria. Moreover, ozone disinfection inactivated or damaged the opportunistic pathogens due to its strong oxidizing properties. The damaged bacteria resulting from initial ozone treatment were inactivated by the subsequent chlorine disinfection. Compared with the AR treated with Cl2 alone, the opportunistic pathogens M. auium and L. pneumophila were not detectable in effluents of the AR treated with O3/Cl2, and decreased to （4.60 ± 0.14） and （3.09 ± 0.12） loglo （gene copies/g corrosion scales） in biofilms, respectively. The amoeba counts were also lower in the AR treated with O3/Cl2. Therefore, O3/Cl2 disinfection can effectively control opportunistic pathogens in effluents and biofilms of an AR used as a model for a drinking water distribution system.
基金supported by the National Natural Science Foundation of China[No.51878468 and No.51508397]the Hospital Management Research Fund of Shanghai Medical Association[No.Q1902037]+1 种基金the Fundamental Research Funds for the Central Universitiesthe National Major Science and Technology Project for Water Pollution Control and Treatment[No.2017ZX07201002]。
文摘Objective Our objective was to investigate the occurrence of opportunistic pathogens and characterize the bacterial community structures in the water system of a pulmonary hospital.Methods The water samples were collected from automatic and manual faucets in the consulting room,treatment room,dressing room,respiratory ward,and other non-medical rooms in three buildings of the hospital.Quantitative polymerase chain reaction was used to quantify the load of several waterborne opportunistic pathogens and related microorganisms,including Legionella spp.,Mycobacterium spp.,and M.avium.Illumina sequencing targeting 16 S r RNA genes was performed to profile bacterial communities.Results The occurrence rates of Legionella spp.,Mycobacterium spp.,and M.avium were 100%,100%,and 76%,respectively in all samples.Higher occurrence rates of M.avium were observed in the outpatient service building(building 1,91.7%)and respiration department and wards(building 2,80%)than in the office building(building 3),where no M.avium was found.M.avium were more abundant in automatic faucets(average 2.21×10~4 gene copies/L)than in manual faucets(average 1.03×10~4 gene copies/m L)(P<0.01).Proteobacteria,Actinobacteria,Bacteroidetes,Cyanobacteria,Firmicutes,and Acidobacteria were the dominant bacterial phyla.Disinfectant residuals,nitrate,and temperature were found to be the key environmental factors driving microbial community structure shifts in water systems.Conclusion This study revealed a high level of colonization of water faucets by opportunistic pathogens and provided insight into the characteristics of microbial communities in a hospital water system and approaches to reduce risks of microbial contamination.
基金funded by the National Natural Science Foundation of China(Nos.51878654,52070189,51838005)the National Key R&D Program of China(Nos.2019YFD1100105,SQ2018YFE020448)+2 种基金the project of Chinese Academy of Sciences(No.QYZDY-SSW-ZQC004)Major Science and Technology Program for Water Pollution Control and Treatment(Nos.2017ZX07108,2017ZX07501-002)。
文摘Many problems in drinking water distribution systems(DWDSs)are caused by microbe,such as biofilm formation,biocorrosion and opportunistic pathogens growth.More iron release from corrosion scales may induce red water.Biofilm played great roles on the corrosion.The iron-oxidizing bacteria(IOB)promoted corrosion.However,when iron-reducing bacteria(IRB)and nitrate-reducing bacteria(NRB)became the main bacteria in biofilm,they could induce iron redox cycling in corrosion process.This process enhanced the precipitation of iron oxides and formation of more Fe3 O4 in corrosion scales,which inhibited corrosion effectively.Therefore,the IRB and NRB in the biofilm can reduce iron release and red water occurrence.Moreover,there are many opportunistic pathogens in biofilm of DWDSs.The opportunistic pathogens growth in DWDSs related to the bacterial community changes due to the effects of micropollutants.Micropollutants increased the number of bacteria with antibiotic resistance genes(ARGs).Furthermore,extracellular polymeric substances(EPS)production was increased by the antibiotic resistant bacteria,leading to greater bacterial aggregation and adsorption,increasing the chlorine-resistance capability,which was responsible for the enhancement of the particle-associated opportunistic pathogens in DWDSs.Moreover,O3-biological activated carbon filtration-UV-Cl2 treatment could be used to control the iron release,red water occurrence and opportunistic pathogens growth in DWDSs.
基金the National Natural Science Foundation of China （Nos. 30370951, 30270891）.
文摘Burkholderia cepacia （Bc） and Pseudomonas aeruginosa （Pa） are both biocontrol agents in agriculture and opportunistic human pathogens in hospitals. Effective management and utilization practice is needed to understand their characteristics and distribution in rice. During the last decade, the two opportunistic human pathogens were detected in 631 samples of rice seed and 117 samples of rice plant in plain, highland and mountainous rice growing areas of China. Bc and Pa were primarily differentiated by common bacteriological characteristics and pathogenic tests and then identified into species by Biolog and FAME tests. However, the genotypes of Bc still could not be distinguished. It has been noted that the Bc and Pa mainly existed in rice root with the highest distribution frequency in plain areas （ 6.1% and 16.1%） and lowest in the mountainous areas （1.0% and 7.8%）.
文摘White-nose syndrome(WNS)has caused recent catastrophic declines among multiple species of bats in eastern North America.The disease's name derives from a visually apparent white growth of the newly discovered fungus Geomyces destructans on the skin(including the muzzle)of hibernating bats.Colonization of skin by this fungus is associated with characteristic cutaneous lesions that are the only consistent pathological finding related to WNS.However,the role of G.destructans in WNS remains controversial because evidence to implicate the fungus as the primary cause of this disease is lacking.The debate is fuelled,in part,by the assumption that fungal infections in mammals are most commonly associated with immune system dysfunction.Additionally,the recent discovery that G.destructans commonly colonizes the skin of bats of Europe,where no unusual bat mortality events have been reported,has generated further speculation that the fungus is an opportunistic pathogen and that other unidentified factors are the primary cause of WNS.
基金financially supported by Hunan Provincial Science&Technology Major Project(2022sfq30,20231F18)National Natural Science Foundation of China(32173021)+4 种基金Natural Science Foundation of Hunan Province(2024JJ5184)Key Projects of Hunan Provincial Education Department(23A0196)Science Fund for Distinguished Young Scholars of Hunan Province(2025JJ20024)Earmarked Fund for Hunan Agriculture Research System(HARS-07)Earmarked Fund for China Agriculture Research System(CARS-45-48)。
文摘The dissemination of antibiotic resistance genes(ARGs)has emerged as a global public health concern.However,the distribution and driving factors of ARGs,especially high-risk ARGs,in the fish gut from natural water eco-systems remain largely unclear.In the present study,high-throughput quantitative PCR(HT-qPCR)and 16S rRNA gene sequencing were deployed to determine the ARG profiles and microbial communities in the fish gut across 13 sampling sites from the Xiangjiang River,one of the major tributaries of the Yangtze River in China.In total,120 ARG subtypes were identified,dominated by macrolide-lincosamide-streptogramin B(MLSB)resis-tance genes.The abundance of ARGs varied across sampling sites,with highest at Xiangxiang(XX)and lowest at Chaling(CL).Furthermore,it was observed that ARG abundance was higher in the tributaries compared to the trunk stream,with an increasing trend from upstream to downstream.At the ranks of phylum and genus,the fish gut microbiota was predominantly composed of Proteobacteria and Escherichia,respectively.Several opportu-nistic pathogens(Vibrio,Streptococcus,and Pseudomonas)exhibited significantly positive correlations with high-risk ARGs(floR,emrB,and ermD).Finally,the assembly of ARGs in the Xiangjiang River was dominated by deterministic processes and significantly influenced by mobile genetic elements(MGEs),environmental factors,heavy metals,and geographic location.Overall,the findings of this study illustrate the prevalence of ARGs and opportunistic pathogens in the fish gut within the Xiangjiang River,highlighting potential risks to public health.These results provide valuable insights for developing targeted strategies to manage and assess ARGs in natural water ecosystems.
基金supported by ICMR-RMRC intramural fund(RMRC/IM/2022/26).
文摘Acinetobacter(A.)baumannii is a Gram-negative,non-fermenting opportunistic pathogen increasingly implicated in nosocomial infections,particularly in intensive care units(ICUs).Its ability to acquire multidrug resistance(MDR),including to carbapenems,poses a major public health threat.Infections caused by A.baumannii-ranging from pneumonia to bloodstream and wound infections-are difficult to treat and associated with high mortality,especially in critically ill patients[1].
基金Project supported by the National Natural Science Foundation of China (No. 30871130)the Youth Talent Special Fund of the Health Bureau of Zhejiang Province, China (No. 2008QN016)
文摘Rhodococcus equi, previously known as Corynebacterium equi, is one of the most important causes of zoonotic infections in grazing animals. Increased cases of human infection with R. equi have been reported, especially in immunocompromised patients, within recent years. We present a case of R. equi bacteremia in a 51-year-old man with diabetes and liver cirrhosis, on long-term corticosteroid therapy after skin-grafting surgery. The patient recovered soon after he was treated with vancomycin. This review focuses on the microbiological characteristics of this organism, and the diagnosis and treatment of this infection.
基金supported by the National Key R&D Program of China(No.2016YFC0400803)the National Natural Science Foundation of China(No.51678558)the National Water Pollution Control and Treatment Special Key Project of China(No.2017ZX07108-002)
文摘This study profiled the bacterial community variations of water from four water treatment systems,including coagulation,sedimentation,sand filtration,ozonation-biological activated carbon filtration(O3-BAC),disinfection,and the tap water after the distribution process in eastern China.The results showed that different water treatment processes affected the bacterial community structure in different ways.The traditional treatment processes,including coagulation,sedimentation and sand filtration,reduced the total bacterial count,while they had little effect on the bacterial community structure in the treated water(before disinfection).Compared to the traditional treatment process,O3-BAC reduced the relative abundance of Sphingomonas in the finished water.In addition,ozonation may play a role in reducing the relative abundance of Mycobacterium.NaClO and ClO2 had different effects on the bacterial community in the finished water.The relative abundance of some bacteria(e.g.Flavobacterium,Phreatobacter and Porphyrobacter)increased in the finished water after ClO2 disinfection.The relative abundance of Mycobacterium and Legionella,which have been widely reported as waterborne opportunistic pathogens,increased after NaClO disinfection.In addition,some microorganisms proliferated and grew in the distribution system,which could lead to turbidity increases in the tap water.Compared to those in the finished water,the relative abundance of Sphingomonas,Hyphomicrobium,Phreatobacter,Rheinheimera,Pseudomonas and Acinetobacter increased in the tap water disinfected with NaClO,while the relative abundance of Mycobacterium increased in the tap water disinfected with ClO2.Overall,this study provided the detailed variation in the bacterial community in the drinking water system.
基金supported by projects CGL2009-12753-C02-01/BOS,CGL2010-15726,and PID2019-109685GB-I100 of the Spanish Ministry of Science,Innovation and Universities.
文摘Anthropogenic stressors can favor the occurrence of noninfectious disease that can be worsened by the impact of opportunistic pathogens,making the epizootiology of environmental diseases difficult to unravel.The incidence and impact of oral lesions in nestlings of a facultative scavenger species,the black kite Milvus migrans,were examined over seven breeding seasons in the highly degraded environment close to Madrid,Spain.We found an overall prevalence of 31%of nestlings with oral lesions,with no clear spatial pattern in nests with affected and unaffected individuals.The occurrence and number of oral lesions were negatively associated with nestling body condition and brood size.Broods,where all siblings had oral lesions,were smaller than those where some or all siblings were apparently healthy,suggesting that oral disease could be causing nestling mortality and,consequently,brood size reduction.In turn,nestling body condition was negatively affected by lesion occurrence,brood size,and laying date.Although these relationships were bidirectional,piecewise structural equation modeling analyses showed a greater negative effect of body condition on lesion occurrence than vice versa,indicating that nestlings in poorer body condition were more likely to develop oral lesions(which could contribute to aggravate their state of deterioration)than those in better condition.Nestlings from small broods were also more likely to have oral disease(directly or indirectly through their lower body condition)than nestlings from large broods.Nestlings that hatched last in the broods showed greater development stress than those that hatched first.Anthropogenic stressors could trigger poor body condition,and contribute to microbiota dysbiosis-related diseases.Although further research is needed to determine the consequences for the long-term fitness of individuals,actions should be taken to mitigate adverse conditions that may favor the appearance of environmental diseases associatedwithperi-urbanareas,giventheirrapidexpansion overnatural areas.
基金the MOST Key Research and Development Program of China(grant number 2022YFC2304703)the Natural Science Foundation of China(grant number 32422004)+5 种基金The Medicine and Engineering Interdisciplinary Research Fund of Shanghai Jiao Tong University(grant number 24X010301328)the Natural Science Foundation of China(grant number 32270202)the Computational Biology Program of Science and Technology Commission of Shanghai Municipality(STCSM)(grant number 25JS2810200)the MOST Key Research and Development Program of China(grant number 2020YFA0907200)Program of Shanghai Academic Research Leader(grant number 23XD1422300)Innovative research team of high-level local universities in Shanghai.All funding sources are attributed to N.N.L.
文摘Postoperative infection is a major global health concern,affecting 5%-10%of surgical patients and nearly doubling mortality in severe cases[1].Transplant recipients are particularly vulnerable,with 30%-80%developing infections within 30 days,often from opportunistic pathogens[2,3].Key risk factors include epidemiological exposure,net immunosuppression,age,transplant type,and surgical history[4].Despite known infection risks,current evidence remains transplantation type-specific and neglects behavioral modulators[5].Different types of transplantation may share similar risk factors[6].To identify common factors affecting postoperative infection,this study collected standardized clinical data-including diet,psychological response,medication use,and biochemical indicators-from liver and kidney transplant patients across six hospitals using a unified standard operating procedure(SOP).
基金supported by grants from the National Key Research and Development Program of China(No.2022YFE0199800)Qingdao Science and Technology Wellness Promotion Demonstration Program(No.24-1-8-smjk-13-nsh)+4 种基金the National Natural Science Foundation of China(No.82271658)the SKLMT Frontiers and Challenges Project(No.SKLMTFCP-2023-01)the Shandong Provincial Natural Science Foundation(Nos.ZR2024QD228 and ZR2024QC311)the Qingdao Natural Science Foundation(No.24-4-4-zrjj-40-jch)the Opening Project of the Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP)(No.FDLAP24008).
文摘To the Editor:Klebsiella pneumoniae(K.pneumoniae)is a common opportunistic pathogen with rising prevalence in clinical settings.A multicenter study reported its detection rate among hospitalized adults with community-acquired pneumonia(CAP)has increased annually,making it the leading cause of severe CAP(SCAP),surpassing Streptococcus pneumoniae.[1]Hypervirulent K.pneumoniae(hvKP),especially sequence type(ST)23,[2]exhibits enhanced virulence and colonization,driven by multiple siderophore systems and virulence plasmids,and is linked to high mortality.[3]Alarmingly,tigecycline resistance in ST23 strains is increasing.While tigecycline is crucial for treating multidrug-resistant and carbapenem-resistant K.pneumoniae,resistance—mainly due to efflux pump overexpression,enzymatic inactivation,and target site mutations—has been widely reported.[4]Mutations in regulators such as RamR(a TetR-family transcriptional repressor regulating ramA)are involved,[5]but their roles in hvKP remain unclear.In this study,a novel RamR point mutation was identified and validated via whole-genome sequencing,gene editing,quantitative real-time polymerase chain reaction(qRT-PCR),proteomics,and electrophoretic mobility shift assay(EMSA).This mutation reduced ramA repression,resulting in efflux pump overexpression,and conferred tigecycline resistance.The Medical Ethics Committee of Qingdao Municipal Hospital approved this study(No.XM:2023-030).
基金supported by Beijing Key Clinical Specialty Funding(No.010071)the Clinical Cohort Construction Program of Peking University Third Hospital(No.BYSYDL2019007)+1 种基金Clinical Key Project of Peking University Third Hospital(No.BYSYZD2022007)Peking University Outstanding Doctoral Student Innovation Funding(No.BMU2024BSS001).
文摘To the Editor:Klebsiella pneumoniae(KP)is a common opportunistic pathogen causing potentially life-threatening illness and organ failure.Surveillance data from the 2023 China Antimicrobial Surveillance Network(CHINET)revealed that the KP isolation rate from clinical respiratory specimens in China was the highest(18.1%)among all bacteria.[1]Both classical(cKP)and hypervirulent KP(hvKP)exert significant effects on the systemic inflammatory response,causing infection-related anemia and high mortality to host.The main gap in current research is that the specific virulence factors of KP that cause host infectious anemia have not been identified.
文摘Urban life has led to the creation of human-made environments that,from a microbiological perspective,provide extreme life conditions.Certain non-ubiquitous microorganisms such as thermophilic members of the black yeast genus Exophiala are enriched within these habitats for which no counterpart is known in nature.Dishwashers consistently accumulate a number of specific black,white and red yeasts on the rubber seals of doors and in stagnant water at the interior.Several of these yeasts are primarily known as agents of human opportunistic infections.In this review,the literature data are supported by a screening study involving 937 households in 15 cities in Turkey.Fungi were detected in 230 samples(24.5%).Using rDNA sequencing,the prevalent species were identified as Exophiala dermatitidis(n=116),Candida parapsilosis(n=44),E.phaeomuriformis(n=35),Magnusiomyces capitatus(n=22),Rhodotorula mucilaginosa(n=15),and C.lusitaniae(n=14).The possible role of dishwashers in transmitting disease is discussed.
基金Supported by the National Key Research and Development Program of China(2022YFD1800400)National Natural Science Foundation of China(81991531,32002339)2115 Talent Development Program of China Agricultural University.
文摘What is already known about this topic?Enterococcus spp.,while naturally occurring as commensal bacteria in the gastrointestinal tract of animals and humans,have emerged as significant opportunistic pathogens in healthcare settings.What is added by this report?A comprehensive surveillance study revealed enterococci in 14.39%of clinical samples from dogs and cats across China during 2018–2021.Multidrugresistant enterococcal infections showed significant correlation with urinary tract catheterization and extended hospitalization periods.Notably,pet-derived Enterococcus faecalis isolates demonstrated high genetic similarity with strains isolated from humans,farm animals,and environmental sources.What are the implications for public health practice?These findings underscore the critical need for enhanced surveillance of enterococcal infections and implementation of stringent aseptic protocols in veterinary clinical settings.Particular attention should be directed toward linezolid-resistant Enterococcus faecalis infections due to their demonstrated potential for transmission between pets and humans.
基金supported by the National Key Research and Development Program of China(2022YFC2303200,2020YFA0113400)the National Natural Science Foundation of China(92368112)+4 种基金Beijing Natural Science Foundation(JQ22017)CAS Project for Young Scientists in Basic Research(YSBR-076)Initiative Scientific Research Program of the Institute of Zoology,Chinese Academy of Sciences(2024IOZ0103,2023IOZ0202)State Key Laboratory of Membrane Biology and Key Laboratory of Organ Regeneration and Reconstruction of the Chinese Academy of Sciencessupport from the CAS Key Laboratory of Pathogenic Microbiology and Immunology at Institute of Microbiology.
文摘Dear Editor,In the intestine of humans and other animals,the commensal microbiome has complex roles in shaping infections(Khan et al.,2021).Commensal microbiome contains opportunistic pathogens that are usually suppressed but can cause infection under microbiome dysbiosis or environmental disturbances(Dey and Ray Chaudhuri,2023).
基金supported by the National Natural Science Foundation of China(Grant number 82172326 to W.W.).
文摘Prototheca wickerhamii,an opportunistic pathogen affecting both humans and animals,is widely distributed in the environment,including soil,mud,and water sources such as rivers.However,human infections caused by this genus are rare[1].Unfortunately,due to the nonspecific clinical manifestations and limited awareness among clinicians,protothecosis is often underestimated and misdiagnosed.P.wickerhamii has been shown to exhibit low cytotoxicity tomacrophages,potentially allowing it to evade immune clearance[2].Currently,the highquality genome sequencing technology offers insights into the evolution and pathogenicity of Prototheca while also serving as a genomic resource for improved diagnosis[3].
文摘The genus Aeromonas is considered as indigenous prokaryote to aquatic environments. These genus members are capable of colonizing in water bodies such as potable water, sewage and sea water. Aeromonas sp. is the most significant opportunistic pathogen in humans with the potential to cause different kinds of infections in blood, tissues, intestine, and dermis. The leading pathogenic species includes Aeromonas hydrophila, A. caviae and A. veronii. The ubiquitous nature in the environment associated with the virulence of these bacteria has been reported. Evidence for the waterborne transmission to humans by Aeromonas sp. is also documented. The Aeromonas found in wastewater and its impact on marine environment is hardly discussed and its bibliography is lacking. The aim of this research was to identify the major biomarker genes in Aeromonas sp., and it's in silico sequence analysis.
基金supported by the Natural Science Foundation of Jiangsu Province(BK20230117)the Natural Science Research Project of Nanjing Polytechnic Institute(NJPI-2023-04)the Qinglan Project of Jiangsu Province,and the National Medical Research Council of Singapore(OFIRG21jun-0058 and OFIRG23Jul-0077).
文摘Candida albicans is an opportunistic fungal pathogen of humans.It causes a variety of infections ranging from superficial mucocutaneous conditions to severe systemic diseases that result in substantial morbidity and mortality.This pathogen frequently forms biofilms resistant to antifungal drugs and the host immune system,leading to treatment failures.Recent research has demonstrated the potential of nanorobots to penetrate biological barriers and disrupt fungal biofilms.In this perspective paper,we provide a brief overview of recent breakthroughs in nanorobots for candidiasis treatment and discuss current challenges and prospects.
