On August 14th,2018,a Beijing resident living in Xicheng District found a female H.longicornis tick attached to the skin at the front of his upper shin.On examination,the patient was afebrile and appeared well.The spe...On August 14th,2018,a Beijing resident living in Xicheng District found a female H.longicornis tick attached to the skin at the front of his upper shin.On examination,the patient was afebrile and appeared well.The species of the tick was identified through morphological characteristics and phylogenetic analysis based on cytochrome C oxidase subunit I.This H.longicornis tick was screened for tick-borne pathogens such as viruses,bacteria and parasites.RNA pathogens were screened by PCR and sequencing,while DNA pathogens were screened by metagenomic analyses.It was found that the tick was positive for the DNA sequences of zoonotic and animal pathogens such as A phagocytophilum,Ehrlichia minasensis and C.burnetii.Considering the good health condition of the patient,we hypothesized that the pathogens originated from the tick specimen itself rather than host blood meal.For the first time,our study reveals the possible risk of transmission of tick-borne pathogens to human beings through tick bit in downtown Beijing.Further research is needed to screen for tick-borne pathogens among unfed ticks collected from central Beijing.展开更多
West Nile virus(WNV), a flavivirus of the Flaviviridae family, is maintained in nature in an enzootic transmission cycle between avian hosts and ornithophilic mosquito vectors, although the virus occasionally infects ...West Nile virus(WNV), a flavivirus of the Flaviviridae family, is maintained in nature in an enzootic transmission cycle between avian hosts and ornithophilic mosquito vectors, although the virus occasionally infects other vertebrates. WNV causes sporadic disease outbreaks in horses and humans, which may result in febrile illness, meningitis, encephalitis and flaccid paralysis. Until recently, its medical and veterinary health concern was relatively low; however, the number, frequency and severity of outbreaks with neurological consequences in humans and horses have lately increased in Europe and the Mediterranean basin. Since its introduction in the Americas, the virus spread across the continent with worrisome consequences in bird mortality and a considerable number of outbreaks among humans and horses, which have resulted in the largest epidemics of neuroinvasive WNV disease ever documented. Surprisingly, its incidence in human and animal health is very different in Central and South America, and the reasons for it are not yet understood. Even though great advances have been obtained lately regarding WNV infection, and although efficient equine vaccines are available, no specific treatments or vaccines for humanuse are on the market. This review updates the most recent investigations in different aspects of WNV life cycle: molecular virology, transmission dynamics, host range, clinical presentations, epidemiology, ecology, diagnosis, control, and prevention, and highlights some aspects that certainly require further research.展开更多
Tick-borne diseases(TBDs) are a major public health concern that has increased in the past three decades. Nevertheless, emerging or reemerging TBDs may be still misdiagnosed. Molecular biology techniques for the scree...Tick-borne diseases(TBDs) are a major public health concern that has increased in the past three decades. Nevertheless, emerging or reemerging TBDs may be still misdiagnosed. Molecular biology techniques for the screening of ticks, use of "Omics" approaches and the incorporation of analytical methods such as mass spectrometry or nuclear magnetic resonance, to the study of ticks and their associated pathogens or potential pathogens are promising tools for a more accurate differential diagnosis of TBDs. However, this huge amount of data needs to be carefully interpreted before being incorporated to the routine of clinical practice. In the meantime, a clinical approach and high level of suspicion keep being essential for the diagnosis and proper handling of TBDs.展开更多
The recycling of biowaste from municipal wastewater treatment plants(WWTPs)in agriculture represents a circular economy-driven source of water and nutrients to support food system sustainability.However,biowaste may r...The recycling of biowaste from municipal wastewater treatment plants(WWTPs)in agriculture represents a circular economy-driven source of water and nutrients to support food system sustainability.However,biowaste may represent the source of emerging hazards of anthropogenic and animal origin that can transfer from agricultural soils to related food production,posing a risk to consumers’health,as in the case of outbreaks due to the consumption of ready-to-eat leafy vegetables contaminated with pathogenic E.coli.From this perspective,we propose a combined strategy based on both classical methods and culture-independent metagenomics approaches to identify microbial hazards relevant to foodborne diseases in WWTP-related biowastes.The virulence genes targeted by real-time PCR,performed before and after the enrichment of the raw samples,may represent a proxy for the viability of pathogens,the presence of which is then confirmed via classical microbiological methods.Bioinformatics analysis of shotgun metagenomic sequences could assess the presence of genes associated with resistance to specific antimicrobials followed by phenotypic confirmation via cultivation of the raw samples in the presence of the predicted molecules.Bacterial 16S rDNA analysis supports biowaste traceability based on their taxonomic composition.This strategy would support a“One Health”Action based on a cross-cutting assessment of emerging food-borne risks along the food chain.展开更多
Objective:To determine the prevalence of tick-borne pathogens with a particular focus on Rickettsia spp.in ticks collected from cattle in Gauteng and Limpopo Provinces,South Africa.Methods:A total of 200 ticks were co...Objective:To determine the prevalence of tick-borne pathogens with a particular focus on Rickettsia spp.in ticks collected from cattle in Gauteng and Limpopo Provinces,South Africa.Methods:A total of 200 ticks were collected from cattle within the Madala livestock,Pretoria,Gauteng Province and in Mankweng Township,Polokwane,Limpopo Province in 2019.The ticks were morphologically identified and processed individually for a total genomic DNA extraction.Specific primers targetting ompA,ompB,and the 17KDa genes were used for a molecular screening and delineation of Rickettsia from the extracted genetic materials using polymerase chain reaction(PCR)technique.PCR amplicons of positive samples were sequenced bidirectionally using the Sanger sequencing method.Sequences generated were processed and analysed using appropriate bioinformatics software.Results:The ticks were morphologically identified as Amblyomma spp.PCR profiling of the genomic DNA samples revealed the presence of the Rickettsia pathogen in 42(21%)of the ticks collected from both Provinces.Out of the genes profiled,14(7%)were positive for 17KDa,42(21%)for ompA and 32(16%)were positive for ompB genes respectively.The nucleotide blast of the sequenced genomes showed high similarity,as high as 100% with other reference Rickettsia(R.)africae in the GenBank.The phylogenetic analysis of the sequences further validated them as R.africae with their characteristic clustering pattern with related reference sequences.Conclusions:There is an abundance of R.africae in Amblyomma ticks collected from cattle in the study areas.This has serious public health implications as individuals who accidentally get infested with the ticks could acquire R.africae.Hence,adequate precautions in terms of sensitization of farmers about the risk and mass mobilization drive to control the vectors in the areas are highly recommended to safeguard public health.展开更多
目的:分析南京医科大学第一附属医院急诊重症监护病房(emergency intensive care unit,EICU)医院感染病原菌分布及其耐药现状,为临床合理用药和控制医院感染提供依据。方法:对2006年1月～2007年6月该院EICU医院感染患者的各类标本中分...目的:分析南京医科大学第一附属医院急诊重症监护病房(emergency intensive care unit,EICU)医院感染病原菌分布及其耐药现状,为临床合理用药和控制医院感染提供依据。方法:对2006年1月～2007年6月该院EICU医院感染患者的各类标本中分离出的病原菌,采用K-B纸片扩散法进行敏感试验,对致病菌耐药率进行分析。结果:EICU医院感染病原菌多为耐药菌,病原菌以革兰阴性杆菌(G-)为主占65.33%、革兰阳性球菌(G+)第二占18.29%、真菌第三占16.38%;革兰阴性杆菌中以铜绿假单胞菌、鲍氏不动杆菌、肺炎克雷伯菌及大肠埃希菌为主;革兰阳性菌主要以葡萄球菌属为主;真菌以白假丝酵母、光滑假丝酵母菌为主。大肠埃希菌和肺炎克雷伯菌的产超广谱耐β-内酰胺酶(ESBLs)菌检出率分别为58.06%和30.00%;耐甲氧西林葡萄球菌(MRS)检出率为71.87%。结论:加强对EICU病原菌分布及耐药率监测,同时依据细菌病原学及抗菌药物敏感性结果,选择抗菌药物,以减少新的耐药株的出现,降低医院感染率。展开更多
目的总结急诊重症监护病房(emergency intensive care unit,EICU)感染因素、感染病原学分布,分析药物敏感性。方法回顾性分析2009年7月至2012年6月205例EICU感染病例的感染部位、感染因素、病原菌分布及对抗菌药物的敏感性。结果 EICU...目的总结急诊重症监护病房(emergency intensive care unit,EICU)感染因素、感染病原学分布,分析药物敏感性。方法回顾性分析2009年7月至2012年6月205例EICU感染病例的感染部位、感染因素、病原菌分布及对抗菌药物的敏感性。结果 EICU患者感染部位以下呼吸道最多,占57.6%。发生感染者多为高龄、住院时间长、伴有基础病及侵入性操作者。EICU感染病原菌以革兰阴性菌为主,占72.0%,革兰阳性菌占19.9%,真菌占8.2%。大肠埃希菌对头孢他啶、头孢吡肟、碳青霉烯类、哌拉西林/他唑巴坦、头孢哌酮/舒巴坦、阿米卡星的敏感率﹥75.0%;铜绿假单胞菌仅对头孢他啶、碳青霉烯类、头孢哌酮/舒巴坦敏感,其敏感率﹥75.0%;鲍曼不动杆菌仅对碳青霉烯类、头孢哌酮/舒巴坦敏感,其敏感率﹥75.0%;肺炎克雷伯菌对头孢他啶、头孢吡肟、碳青霉烯类、哌拉西林/他唑巴坦的敏感率﹥75.0%;肠球菌和金黄色葡萄球菌对糖肽类抗菌药物的敏感率为100.0%。结论 EICU患者高龄多伴有基础病、接受侵入性操作多、抗菌药物联合应用多,均是造成EICU感染的因素,常见病原菌多为耐药菌,应结合药敏结果合理选用抗菌药物。展开更多
基金This study was funded by the national key research and development programs of China(No.2017YFD0501803 and 2016YFD0501100)the Young Talents Program of the Chinese Academy of Inspection and Quarantine.
文摘On August 14th,2018,a Beijing resident living in Xicheng District found a female H.longicornis tick attached to the skin at the front of his upper shin.On examination,the patient was afebrile and appeared well.The species of the tick was identified through morphological characteristics and phylogenetic analysis based on cytochrome C oxidase subunit I.This H.longicornis tick was screened for tick-borne pathogens such as viruses,bacteria and parasites.RNA pathogens were screened by PCR and sequencing,while DNA pathogens were screened by metagenomic analyses.It was found that the tick was positive for the DNA sequences of zoonotic and animal pathogens such as A phagocytophilum,Ehrlichia minasensis and C.burnetii.Considering the good health condition of the patient,we hypothesized that the pathogens originated from the tick specimen itself rather than host blood meal.For the first time,our study reveals the possible risk of transmission of tick-borne pathogens to human beings through tick bit in downtown Beijing.Further research is needed to screen for tick-borne pathogens among unfed ticks collected from central Beijing.
基金Supported by Grants No.RTA2011-00036,SAF2008-04232 and FAU2008-00006 from the Spanish Ministerio de Ciencia e Innovaciónthe European Community’s Seventh Framework Programme(No.FP/2007-2013)under Grant Agreement 28394
文摘West Nile virus(WNV), a flavivirus of the Flaviviridae family, is maintained in nature in an enzootic transmission cycle between avian hosts and ornithophilic mosquito vectors, although the virus occasionally infects other vertebrates. WNV causes sporadic disease outbreaks in horses and humans, which may result in febrile illness, meningitis, encephalitis and flaccid paralysis. Until recently, its medical and veterinary health concern was relatively low; however, the number, frequency and severity of outbreaks with neurological consequences in humans and horses have lately increased in Europe and the Mediterranean basin. Since its introduction in the Americas, the virus spread across the continent with worrisome consequences in bird mortality and a considerable number of outbreaks among humans and horses, which have resulted in the largest epidemics of neuroinvasive WNV disease ever documented. Surprisingly, its incidence in human and animal health is very different in Central and South America, and the reasons for it are not yet understood. Even though great advances have been obtained lately regarding WNV infection, and although efficient equine vaccines are available, no specific treatments or vaccines for humanuse are on the market. This review updates the most recent investigations in different aspects of WNV life cycle: molecular virology, transmission dynamics, host range, clinical presentations, epidemiology, ecology, diagnosis, control, and prevention, and highlights some aspects that certainly require further research.
文摘Tick-borne diseases(TBDs) are a major public health concern that has increased in the past three decades. Nevertheless, emerging or reemerging TBDs may be still misdiagnosed. Molecular biology techniques for the screening of ticks, use of "Omics" approaches and the incorporation of analytical methods such as mass spectrometry or nuclear magnetic resonance, to the study of ticks and their associated pathogens or potential pathogens are promising tools for a more accurate differential diagnosis of TBDs. However, this huge amount of data needs to be carefully interpreted before being incorporated to the routine of clinical practice. In the meantime, a clinical approach and high level of suspicion keep being essential for the diagnosis and proper handling of TBDs.
基金supported by the Italian Ministry of Health grant no.RF-2019-12369714,PI Stefano Morabito.
文摘The recycling of biowaste from municipal wastewater treatment plants(WWTPs)in agriculture represents a circular economy-driven source of water and nutrients to support food system sustainability.However,biowaste may represent the source of emerging hazards of anthropogenic and animal origin that can transfer from agricultural soils to related food production,posing a risk to consumers’health,as in the case of outbreaks due to the consumption of ready-to-eat leafy vegetables contaminated with pathogenic E.coli.From this perspective,we propose a combined strategy based on both classical methods and culture-independent metagenomics approaches to identify microbial hazards relevant to foodborne diseases in WWTP-related biowastes.The virulence genes targeted by real-time PCR,performed before and after the enrichment of the raw samples,may represent a proxy for the viability of pathogens,the presence of which is then confirmed via classical microbiological methods.Bioinformatics analysis of shotgun metagenomic sequences could assess the presence of genes associated with resistance to specific antimicrobials followed by phenotypic confirmation via cultivation of the raw samples in the presence of the predicted molecules.Bacterial 16S rDNA analysis supports biowaste traceability based on their taxonomic composition.This strategy would support a“One Health”Action based on a cross-cutting assessment of emerging food-borne risks along the food chain.
基金funded by SAMRC with grant number RDG2017/18 and the APC was funded by SMU.
文摘Objective:To determine the prevalence of tick-borne pathogens with a particular focus on Rickettsia spp.in ticks collected from cattle in Gauteng and Limpopo Provinces,South Africa.Methods:A total of 200 ticks were collected from cattle within the Madala livestock,Pretoria,Gauteng Province and in Mankweng Township,Polokwane,Limpopo Province in 2019.The ticks were morphologically identified and processed individually for a total genomic DNA extraction.Specific primers targetting ompA,ompB,and the 17KDa genes were used for a molecular screening and delineation of Rickettsia from the extracted genetic materials using polymerase chain reaction(PCR)technique.PCR amplicons of positive samples were sequenced bidirectionally using the Sanger sequencing method.Sequences generated were processed and analysed using appropriate bioinformatics software.Results:The ticks were morphologically identified as Amblyomma spp.PCR profiling of the genomic DNA samples revealed the presence of the Rickettsia pathogen in 42(21%)of the ticks collected from both Provinces.Out of the genes profiled,14(7%)were positive for 17KDa,42(21%)for ompA and 32(16%)were positive for ompB genes respectively.The nucleotide blast of the sequenced genomes showed high similarity,as high as 100% with other reference Rickettsia(R.)africae in the GenBank.The phylogenetic analysis of the sequences further validated them as R.africae with their characteristic clustering pattern with related reference sequences.Conclusions:There is an abundance of R.africae in Amblyomma ticks collected from cattle in the study areas.This has serious public health implications as individuals who accidentally get infested with the ticks could acquire R.africae.Hence,adequate precautions in terms of sensitization of farmers about the risk and mass mobilization drive to control the vectors in the areas are highly recommended to safeguard public health.
文摘目的:分析南京医科大学第一附属医院急诊重症监护病房(emergency intensive care unit,EICU)医院感染病原菌分布及其耐药现状,为临床合理用药和控制医院感染提供依据。方法:对2006年1月～2007年6月该院EICU医院感染患者的各类标本中分离出的病原菌,采用K-B纸片扩散法进行敏感试验,对致病菌耐药率进行分析。结果:EICU医院感染病原菌多为耐药菌,病原菌以革兰阴性杆菌(G-)为主占65.33%、革兰阳性球菌(G+)第二占18.29%、真菌第三占16.38%;革兰阴性杆菌中以铜绿假单胞菌、鲍氏不动杆菌、肺炎克雷伯菌及大肠埃希菌为主;革兰阳性菌主要以葡萄球菌属为主;真菌以白假丝酵母、光滑假丝酵母菌为主。大肠埃希菌和肺炎克雷伯菌的产超广谱耐β-内酰胺酶(ESBLs)菌检出率分别为58.06%和30.00%;耐甲氧西林葡萄球菌(MRS)检出率为71.87%。结论:加强对EICU病原菌分布及耐药率监测,同时依据细菌病原学及抗菌药物敏感性结果,选择抗菌药物,以减少新的耐药株的出现,降低医院感染率。
