Genetic and pathogenic characterization of new infectious bronchitis virus strains in the GVI-1 and GI-19 lineages isolated in central China

Avian infectious bronchitis(IB)is a highly contagious infectious disease caused by infectious bronchitis virus(IBV),which is prevalent in many countries worldwide and causes serious harm to the poultry industry.At present,many commercial IBV vaccines have been used for the prevention and control of IB;however,IB outbreaks occur frequently.In this study,two new strains of IBV,SX/2106 and SX/2204,were isolated from two flocks which were immunized with IBV H120 vaccine in central China.Phylogenetic and recombination analysis indicated that SX/2106,which was clustered into the GI-19 lineage,may be derived from recombination events of the GI-19 and GI-7 strains and the LDT3-A vaccine.Genetic analysis showed that SX/2204 belongs to the GVI-1 lineage,which may have originated from the recombination of the GI-13 and GVI-1 strains and the H120 vaccine.The virus cross-neutralization test showed that the antigenicity of SX/2106 and SX/2204 was different from H120.Animal experiments found that both SX/2106 and SX/2204 could replicate effectively in the lungs and kidneys of chickens and cause disease and death,and H120 immunization could not provide effective protection against the two IBV isolates.It is noteworthy that the pathogenicity of SX/2204 has significantly increased compared to the GVI-1 strains isolated previously,with a mortality rate up to 60%.Considering the continuous mutation and recombination of the IBV genome to produce new variant strains,it is important to continuously monitor epidemic strains and develop new vaccines for the prevention and control of IBV epidemics.

Pathogenic Antigenic and Molecular Characterization of the Very Virulent Strain(Gx) of Infectious Bursal Disease Virus Isolated in China

The very virulent infectious bursal disease virus (vvIBDV) strain Gx was isolated from a poutl-try farm in Guangxi Province, China, during 1996. The mortality in the infected flock was 80% and occurred 5 days after immunization with serotype I IBD vaccine. The results of antigen-capture ELISA (AC-ELISA), pathogenicity testing, cloning and sequence analysis of the VP2 gene showed that the deduced amino acid sequence of strain Gx VP2 was the same as vvIBDV UK661, which is considered as a reference strain for European vvIBDVs. The antigenicity of the Gx strain was the same as an European vvIBDV strain 849. The EID50 of Gx virus was 10-8.25/0. 2 ml, and the mortality was 64% when 4 week-old SPF chickens were challenged at dosage of 2×10~3EID50. We have demonstrated that the IBDV strain Gx isolated in China is vvIBDV according to European standards.

Diagnosis and Treatment of Rex Rabbit Infectious Coryza and Isolation of the Pathogen

Rex rabbit Bordetella bronchiseptica was isolated from a large rabbit field in Shandong Province. And which could be diagnosed to be Rex rabbit infectious coryza combining with the incidence,clinical symptoms,pathological changes and laboratory examination. Kanamycin soluble powder was used to treat the disease according to the antibiotics usage and course,and the treatment was proved to be effective.

Application of Nanopore Sequencing Technology in the Clinical Diagnosis of Infectious Diseases

Infectious diseases are an enormous public health burden and a growing threat to human health worldwide.Emerging or classic recurrent pathogens,or pathogens with resistant traits,challenge our ability to diagnose and control infectious diseases.Nanopore sequencing technology has the potential to enhance our ability to diagnose,interrogate,and track infectious diseases due to the unrestricted read length and system portability.This review focuses on the application of nanopore sequencing technology in the clinical diagnosis of infectious diseases and includes the following:(i)a brief introduction to nanopore sequencing technology and Oxford Nanopore Technologies(ONT)sequencing platforms;(ii)strategies for nanopore-based sequencing technologies;and(iii)applications of nanopore sequencing technology in monitoring emerging pathogenic microorganisms,molecular detection of clinically relevant drug-resistance genes,and characterization of disease-related microbial communities.Finally,we discuss the current challenges,potential opportunities,and future outlook for applying nanopore sequencing technology in the diagnosis of infectious diseases.

Comparing invasive effects of five foodborne bacterial pathogens in human embryonic intestine 407 cells and human ileocecum HCT-8 cells

Objective: To refine the infectious doses of enteric bacterial pathogens in animal assays and vaccine clinical trials by studying the invasion kinetics of five bacterial pathogens with human intestinal cells.Methods: Utilizing in vitro cultured cell invasion assays with gentamicin-killing step,the invasive effects were analyzed in foodborne pathogens including Salmonella,Shigella, Yersinia, Escherichia coli(E. coli) O157 and opportunistic pathogens Citrobacter in human embryonic intestine 407 cells and ileocecum HCT-8 cells at multiplicities of infection(MOIs) of 0.04–4 000.00 E. coli HS served as a noninvasive control.Results: The study results showed that the bacterial invasive efficiency and the average number of internalized bacteria per host cell changed with different starting MOIs. Higher starting MOIs did not always produce more bacterial internalization. The bacterial invasion effects varied with different bacterial strains and host cell lines. E. coli O157:H7 did invade human ileocecum HCT-8 cells.Conclusions: This study shows that these bacteria possess different invasive patterns at various starting MOIs and also in different cell lines. The results could help to figure out the appropriate infectious doses of the bacteria in animal assays and in vaccine clinical trials. The bacterial invasion kinetics is also valuable in evaluating the safety and efficacy of live attenuated bacterial vaccines.

Post-infectious irritable bowel syndrome:Mechanistic insights into chronic disturbances following enteric infection

Irritable bowel syndrome(IBS)is a commonly encountered chronic functional gastrointestinal(GI)disorder.Approximately 10%of IBS patients can trace the onset of their symptoms to a previous a bout of infectious dysentery.The appearance of new IBS symptoms following an infectious event is defined as post-infectiousIBS.Indeed,with the World Health Organization estimating between 2 and 4 billion cases annually,infectious diarrheal disease represents an incredible international healthcare burden.Additionally,compounding evidence suggests many commonly encountered enteropathogens as unique triggers behind IBS symptom generation and underlying pathophysiological features.A growing body of work provides evidence supporting a role for pathogen-mediated modifications in the resident intestinal microbiota,epithelial barrier integrity,effector cell functions,and innate and adaptive immune features,all proposed physiological manifestations that can underlie GI abnormalities in IBS.Enteric pathogens must employ a vast array of machinery to evade host protective immune mechanisms,and illicit successful infections.Consequently,the impact of infectious events on host physiology can be multidimensional in terms of anatomical location,functional scope,and duration.This review offers a unique discussion of the mechanisms employed by many commonly encountered enteric pathogens that cause acute disease,but may also lead to the establishment of chronic GI dysfunction compatible with IBS.

Analysis of Common Respiratory Infected Pathogens in 3100 Children after the Coronavirus Disease 2019 Pandemic

Objective To investigate the epidemiological features in children after the coronavirus disease 2019(COVID-19)pandemic.Methods This study collected throat swabs and serum samples from hospitalized pediatric patients of Renmin Hospital of Wuhan University,Wuhan,Hubei province,China before and after the COVID-19 pandemic.Respiratory infected pathogens[adenovirus(ADV),influenza virus A/B(Flu A/B),parainfluenza virus 1/2/3(PIV1/2/3),respiratory syncytial virus(RSV),Mycoplasma pneumoniae(MP),and Chlamydia pneumoniae(CP)]were detected.The pathogens,age,and gender were used to analyze the epidemiological features in children after the COVID-19 pandemic.Results The pathogen detection rate was significantly higher in females than in males(P<0.05),and the infection of PIV1 and MP was mainly manifested.After the COVID-19 pandemic,PIV1,PIV3,RSV,and MP had statistically different detection rates among the age groups(P<0.05),and was mainly detected in patients aged 0–6 years,0–3 years,0–3 years,and 1–6 years,respectively.When comparing before the COVID-19 pandemic,the total detection rate of common respiratory pathogens was lower(P<0.05).Except for the increase in the detection rate of PIV1 and CP,the infection rate of other pathogens had almost decreased.Conclusion The prevention and control measures for the COVID-19 pandemic effectively changed the epidemiological features of common respiratory tract infectious diseases in pediatric children.

Construction of Full-length Infectious Clone for Encephalomyocarditis Virus BJC3 and Identification of the Rescued Virus

The objective of this study was to construct the infectious clone of encephalomyocarditis virus (EMCV) BJC3 strain.The genomic cDNA of the virus was amplified by three overlapping segments using RT-PCR,and cloned into low-copy plasmid pWSK29 to construct the full-length cDNA clone pWSKBJC3/ w.The pWSKBJC3/w was in vitro transcribed and transfected into BHK-21 cells to rescue the virus.The results showed that the full-length cDNA clone was infectious and the virus could be rescued in BHK-21 cells.The rescued virus designated RvBJC3W was identified by RT-PCR and indirect immunofluorescence assay(IFA).The rescued virus had similar growth characteristics to its parental virus BJC3 and retained pathogenicity for mice.Our results indicate that the first infectious cDNA clone of EMCV in China has been successfully established and provides an essential tool for investigating the molecular basis of pathogenicity of EMCV.

What is the purpose of launching the World Journal of Clinical Infectious Diseases?

Launching of the World Journal of Clinical Infectious Diseases(WJCID)could have been possible due to efforts of the publisher,members of the editorial board,all the authors and definitely our readers.I congratulate everyone for making it possible.Pathogenic organisms of various origin cause infectious diseases often resulting in symptomatic illness.WJCID is an open access peer reviewed journal that will be published bimonthly.WJCID will primarily emphasize on topics relevant to infections affecting human and animal health yet articles from other diseases and relevant issues will also be encouraged.WJCID welcomes articles from either basic or applied research in different disciplines like Epidemiology of communicable and non-communicable infections,Immunology and Genetics.WJCID covers topics like Host-Parasites interactions,Vector biology,development of advanced tools for diagnosis,genetic susceptibility to diseases,and disease prevention and vector control.WJCID will work as an important resource of basic and applied research in the field of infections.It is widely recommended that clinical implementations of basic and applied research be encouraged for the benefit to each stream.So again I welcome everyone and assure that WJCID will be a great platform where you can feel free to share your valuable results,discuss new hypothesis and research problems and update yourself with the most recent advancements made in the field of infections.

An infection-microenvironment-targeted and responsive peptide-drug nanosystem for sepsis emergency by suppressing infection and inflammation

Sepsis is a life-threatening emergency that causes millions of deaths every year due to severe infection and inflammation.Nevertheless,current therapeutic regimens are inadequate to promptly address the vast diversity of potential pathogens.Omiganan,an antimicrobial peptide,has shown promise for neutralizing endotoxins and eliminating diverse pathogens.However,its clinical application is hindered by safety and stability concerns.Herein,we present a nanoscale drug delivery system(Omi-hyd-Dex@HA NPs)that selectively targets infectious microenvironments(IMEs)and responds to specific stimuli for efficient intervention in sepsis.The system consists of omiganan-dexamethasone conjugates linked by hydrazone bonds which self-assemble into nanoparticles coated with a hyaluronic acid(HA).The HA coating not only facilitates IMEs-targeting through interaction with intercellular-adhesion-molecule-1 on inflamed endotheliocytes,but also improves the biosafety of the nanosystem and enhances drug accumulation in primary infection sites triggered by hyaluronidase.The nanoparticles release dual drugs in IMEs through pH-sensitive cleavage of hydrazone bonds to eradicate pathogens and suppress inflammation.In multiple tissue infection and sepsis animal models,Omi-hyd-Dex@HA NPs exhibited rapid source control and comprehensive inflammation reduction,thereby preventing subsequent fatal complications and significantly improving survival outcomes.The bio-responsive and self-delivering nanosystem offers a promising strategy for systemic sepsis treatment in emergencies.

我国斯里兰卡木薯花叶病毒的分子特征及致病性分析

为进一步探究我国斯里兰卡木薯花叶病毒(Sri Lankan cassava mosaic virus,SLCMV)的分子特征及致病性。以感染SLCMV的木薯叶片基因组DNA为模板,PCR扩增获得DNA-A和DNA-B基因组全长,通过生物信息软件分析比较其核酸及氨基酸序列特征;构建了强、弱致病力分离物(SLCMV-Colombo和SLCMV-DG1922)的侵染性克隆,分别将2种致病力分离物的DNA-A和DNA-B组分进行重组,接种烟草(Nicotianatabacum),比较2种分离物的致病性差异。结果显示:我国SLCMV为“旧世界”双组份菜豆花叶病毒,编码包括AV2基因在内的8个开放阅读框(ORFs);具有双生病毒典型的共同序列(CR)、重复序列、TATABox和TAATATT↓AC茎环结构,Rep蛋白羧基末端有7个氨基酸缺失;我国SLCMV的基因组、编码和非编码区与柬埔寨、泰国和越南分离物的相似性在97.0%~100.0%之间,与印度和斯里兰卡早期的分离物相似性为86.5%~98.6%,DNA-B组份与印度木薯花叶病毒株系(ICMV)编码区序列相似性为95.0%~97.6%,与其他9个非洲木薯花叶病毒株系序列之间的序列相似性均低于80.0%。侵染性克隆接种结果证实,强致病力分离物SLCMV-Col的DNA-A(Col-A)组份在烟草叶片表现典型花叶症状中起主要作用,而我国分离物的DNA-B(DG1922-B)能协同Col-A对烟草产生强致病性。本研究分析了我国SLCMV的全基因组结构,建立的侵染性克隆及其技术为进一步解析SLCMV致病性机理提供重要的研究基础。

滑液囊支原体与鸡传染性支气管炎病毒共感染对SPF鸡的致病性研究

为比较滑液囊支原体(MS)和鸡传染性支气管炎病毒(IBV)共感染对SPF鸡的致病性,本研究将144只28日龄SPF鸡随机均分为阴性对照组、MS感染组、IBV-M41感染组、IBV-M41+MS共感染组、IBV-QX感染组、IBV-QX+MS共感染组共6组,采用50μL/只剂量按相应分组点眼感染MS (106CCU50)、IBV(105EID50),阴性对照组以50μL/只点眼KM2培养基(左眼)和PBS (右眼)。感染后每天观察临床症状,在感染后7 d、14 d、21 d和28 d每组随机剖检6只鸡,观察气囊炎和气囊损伤评分,并采集气管进行病原再分离,其中MS经支原体液体培养基培养后进行PCR鉴定,IBV接种SPF鸡胚后进行RT-PCR鉴定。此外,各组鸡气管均经10%甲醛固定后进行粘膜厚度检测以及病理损伤评分。结果显示:除阴性对照组和MS感染组,其他组鸡在感染后4 d均出现一过性呼吸道症状。剖检结果显示MS感染组鸡在感染后21 d出现气囊炎,28 d仍可见气囊炎;而IBV-M41感染组和IBV-QX感染组鸡在感染后7 d或14 d出现气囊炎,且气囊炎的发生率均未超过50%。感染后14 d IBV-QX+MS共感染组鸡气囊炎发生率达100%(6/6),直至21 d并且大部分鸡气囊炎可持续至感染后28 d (5/6),而IBV-M41+MS共感染组鸡气囊炎仅可持续至感染后21 d,且气囊炎的发生率最高在感染后14 d (5/6)。IBV-QX+MS共感染组鸡平均气囊损伤评分在感染后14 d、21d和28 d均极显著高于单一感染组(P<0.001),而IBV-M41+MS共感染组鸡仅在感染后14 d极显著高于单一感染组(P<0.001)。病原再分离结果显示,各感染组鸡均在气管中再分离到MS(感染后28 d内)或IBV(感染后7 d内)。病理损伤检测结果显示,共感染组鸡较各单一感染组鸡气管粘膜增厚持续时间更长以及病理损伤更为严重。IBV-M41+MS共感染组鸡在感染后14 d平均气管粘膜厚度显著低于IBV-QX+MS共感染组(P<0.05),而在感染后21 d极显著低于IBV-QX+MS共感染组(P<0.001),其余各组鸡在感染后14 d和21 d均极显著低于IBV-QX+MS共感染组鸡(P<0.001)。IBV M41+MS共感染组鸡最早14 d出现气管病变,而IBV QX+MS共感染组鸡在共感染后7 d就可见气管病理损伤,且共感染组鸡的平均气管损伤评分均极显著高于单一MS或IBV感染组(P<0.01或P<0.001)。上述结果证实MS和IBV共感染较单一感染对28日龄SPF鸡的致病性更强,IBV M41或QX株与MS共感染对SPF鸡的致病性存在差异,本研究为临床IB和MS的防控提供科学参考依据。

白带常规与阴道炎六联检在阴道感染性疾病病原体检测中的价值

目的探讨白带常规及阴道炎六联检对阴道感染性疾病中病原体的检测价值。方法以2022年11月—2023年4月在厦门市第三医院接受妇科检查的500例白带异常患者为观察对象,均先后接受白带常规和阴道炎六联检。对比分析单一方法检查和联合检查在阴道感染病原体检测和临床诊断中的效能。结果白带常规检查显示,白细胞(white blood cell,WBC)计数增高141例(28.2%),细菌性感染91例(18.2%),念珠菌感染12例(2.4%),滴虫性感染15例(3.0%),阴道炎检出259例(51.8%);阴道炎六联检显示,WBC计数增高156例(31.2%),细菌性感染95例(19.0%),念珠菌感染35例(7.0%),滴虫性感染28例(5.6%),阴道炎检出314例(62.8%);2项联合检查显示,WBC计数增高158例(31.6%),细菌性感染117例(23.4%),念珠菌感染43例(8.6%),滴虫性感染40例(8.0%),阴道炎检出358例(71.6%),联合检查的细菌性感染、念珠菌感染、滴虫性感染的检出率及阴道炎检出率高于单一检查(P<0.05)。白带常规、阴道炎六联检及联合检测的白带清洁度比较,差异有统计学意义(P<0.05)。结论白带常规联合阴道炎六联检可提高阴道感染性疾病病原体检出率。

危重烧伤患者感染创面病原菌分布耐药性调查研究

目的分析与研究危重烧伤患者创面感染病原菌分布及耐药性。方法选取南阳市中心医院2020年1月至2023年1月96例危重烧伤患者作为研究对象,收集患者创面、静脉血、脓液、痰液等分泌物,另对病原菌感染情况及耐药变化分析。结果96例危重烧伤患者,其中76例感染病原菌,感染率是79.17%,检出病原菌株215株,主要来源于创面分泌物,占37.67%,其次是静脉血、脓液、痰液、其他、尿液,分别占26.98%、12.56%、8.84%、7.44%、6.51%,并且呈逐年递增趋势,检出率由23.26%上升到45.12%;革兰氏阳性菌111株,金黄色葡萄球菌株占16.28%,其中,耐甲氧西林金黄色葡萄球菌(MRSA)占金黄色葡萄球菌40.00%;共91株革兰氏阴性菌,铜绿假单胞菌检出率占14.42%,其次是大肠埃希菌,检出率是8.84%,真菌共13株,占6.05%;MRSA对利奈唑胺、替考拉宁、万古霉素敏感,并未出现耐药菌株,而对氟喹诺酮类、利福平、庆大霉素抗菌药物耐药率均<20%,对红霉素、克林霉素耐药率达85.71%;在革兰氏阴性菌中,铜绿假单胞菌检出率为最高,对头孢唑林、头孢呋辛、头孢呋辛酯、头孢替坦耐药率高,而对氨基糖苷类、喹诺酮类耐药率低;在大肠埃希菌中,对环丙沙星、左氧氟沙星耐药率高,并呈逐年升高趋势,对头孢呋辛、头孢呋辛酯无耐性。结论危重烧伤患者病原菌以金黄色葡萄球菌、铜绿假单胞菌、大肠埃希菌为主,出现多重用药,因此,通过定期监测病原菌分布、耐药性迁移能有效控制耐药菌发展。

广东省番茄白尖曲叶病病原鉴定及其致病性分析

【目的】洋桔梗耳突曲叶病毒(lisianthus enation leaf curl virus,LELCV)是2015年发现的菜豆金色黄花叶病毒属(Begomovirus)病毒新种。论文旨在探究入侵中国内地的首个LELCV分离物Tomato-2022的分子特征、亲缘关系、致病性及有效传播介体,为防控该病毒病提供理论依据。【方法】2022年,在广东省广州市增城区发生一种番茄新病害,病株表现叶小、卷曲、叶尖白化症状,采集两份病样提取总DNA,利用Begomovirus通用引物AV494/CoPR进行PCR检测。选取PCR检测为阳性的样品进行RCA扩增、酶切、克隆及测序,获得分离物Tomato-2022的基因组全长序列。采用BLASTn程序对病毒序列进行相似性检索并下载相似性较高的代表分离物序列,进一步用SDTv1.2的MUSCLE alignment方法进行序列相似性比对;利用软件MEGA7.0对获得的Tomato-2022基因组序列及已报道的相似性较高的代表分离物进行系统发育分析。应用酶切连接法构建Tomato-2022的侵染性克隆pGreenII0229-1.6A,通过农杆菌介导注射接种本氏烟叶片和番茄茎秆,测定其致病性。采取室内人工传毒方法,测定烟粉虱MEAM1隐种对分离物Tomato-2022的传播效率。利用LELCV的PCR特异引物对2021—2023年采集于广东省番茄主产区的135份番茄病样进行检测,明确该病毒在广东省的分布。【结果】PCR检测结果表明,两份表现叶小、卷曲、叶尖白化症状的番茄病样感染了菜豆金色黄花叶病毒属病毒。基因克隆与序列分析显示,该病毒分离物Tomato-2022基因组仅含DNA-A,大小为2757 nt,含有6个ORF。序列相似性比较表明,分离物Tomato-2022基因组序列与已登录GenBank的LELCV各分离物相似性较高,其中与LELCV中国台湾洋桔梗分离物(LC091539、LC091538)相似性最高,为98.33%。系统发育分析显示,Tomato-2022与LELCV的19个分离物聚在一个独立的分支,亲缘关系较近。利用构建的Tomato-2022侵染性克隆pGreenII0229-1.6A,农杆菌介导注射接种本氏烟和番茄,10 dpi,本氏烟上部叶叶缘轻微上卷,1株番茄的新叶轻微卷曲;18 dpi,本氏烟和番茄植株均表现较为明显的卷曲症状;随着接种时间的延长,接种植株的症状越来越明显,30 dpi,本氏烟表现叶脉肿大、叶片严重卷曲,番茄植株的叶片表现卷曲、叶尖白化;PCR检测表明,在接种发病本氏烟和番茄植株中均能检测到LELCV。室内传毒试验证明,烟粉虱MEAM1隐种能高效传播Tomato-2022,当每株番茄接1、5、10头饲毒48 h的烟粉虱时,MEAM1的平均传毒效率分别为26.67%、93.33%、96.67%。PCR检测结果表明,采集的135份番茄病样中,8份样品检测到LELCV,说明LELCV已在广东省定殖。【结论】Tomato-2022是洋桔梗耳突曲叶病毒的一个新分离物,也是在中国内地发现的第一个分离物,其基因组为单链环状DNA,全长为2757 nt,编码6个ORF;该病毒分离物是引起广东省番茄曲叶、叶尖白化病的病原,可被烟粉虱MEAM1隐种高效传播。

鸡群中鸡传染性贫血病原与抗体检测及分离株VP1基因序列分析

为了解鸡群中鸡传染性贫血病毒(CAV)感染及抗体产生情况,从黑龙江省两个无临床症状鸡群(B群和S群)中,分别采集血清通过ELISA方法进行抗体检测,采集抗凝血并分离淋巴细胞,针对基因组保守序列设计引物,通过PCR方法进行病原检测,并对从B群病原阳性鸡分离到的分离株进行VP1基因序列分析。结果显示,B群和S群CAV抗体阳性率分别为62.7%(79/126)和68.2%(88/129),病原阳性率分别为43.0%(49/114)和62.3%(48/77),其中,B群和S群中抗体和病原双阴性的鸡分别为23.7%(27/114)和15.6%(12/77),而抗体和病原双阳性的鸡分别高达28.1%(32/114)和46.8%(36/77);在双阳性鸡中,B群和S群分别有62.5%(20/32)和58.3%(21/36)抗体滴度在1.0×10^(4)及以上,从B群病原阳性鸡全血中分离到一株CAV(HLJ/2022株),分离株HLJ/2022第394位氨基酸为谷氨酰胺,具有强毒的分子特征;两个鸡群的环境拭子CAV阳性率为10.0%(3/30),存在于消毒前的鸡蛋表面、更衣处和鞋底。研究表明,检测鸡群的CAV抗体阳性率在62.7%以上,病原阳性率在43.0%以上,抗体滴度在1.0×104及以上CAV仍可存在,CAV流行株(HLJ/2022)具有强毒分子特征,鸡群环境中存在CAV污染,结果为CIA防控提供重要的参考意见。

2012—2022年合肥市其他感染性腹泻流行特征及病原学检测结果分析

目的了解合肥市其他感染性腹泻(other infectious diarrhea,OID)的流行病学及病原学特征,为防治工作提供科学依据。方法从中国疾病预防控制信息系统中导出合肥市2012—2022年其他感染性腹泻病例报告数据及突发公共卫生事件资料,采用描述流行病学方法,分析报告发病率、病原体构成比、罹患率等指标,探讨三间分布和病原谱特征。结果2012—2022年合肥市共报告其他感染性腹泻病例218484例,年报告发病率范围为158.40/10万~370.50/10万,年均报告发病率245.85/10万,报告发病率总体呈先上升后下降趋势,年度内呈双峰分布,7—8月为夏季高峰,12月—次年1月为冬季高峰。报告病例中,男性123712例,女性94772例,性别比为1.31∶1,男性、女性年均报告发病率分别为271.34/10万、219.01/10万;5岁及以下人群发病141716例(占64.86%);职业分布以散居儿童为主(136294例,占62.38%)。明确病原体诊断的病例有46924例(占21.48%),主要病原体为病毒(44694例,占95.25%),其中轮状病毒感染占88.01%(39337/44694)。2012—2022年合肥市共报告其他感染性腹泻突发公共卫生事件28起,共发病1542例,波及人口62828人,总罹患率为2.45%;其中23起由诺如病毒感染引起,26起发生在学校。结论合肥市其他感染性腹泻报告发病率相对较高,5岁及以下儿童为重点防控人群,轮状病毒为主要病原体,其他感染性腹泻突发公共卫生事件以诺如病毒感染为主。应在流行高峰来临前加强对学校等重点机构和重点人群的健康教育工作,持续做好监测预警和风险评估,提高群众防病意识,落实防控措施。

2020—2023年全国人间传染的病原微生物实验室备案现状分析

为了解2020—2023年全国一级、二级人间传染的病原微生物实验室备案现状,探讨实验室备案工作中存在的问题,针对性提出有效措施,促进实验室监管工作的开展,收集了各省卫生健康主管部门出台的有关实验室备案管理办法,对2020—2023年全国各省人间传染的病原微生物实验室备案数据进行了收集整理,按照不同地区、不同隶属系统,梳理分析了各省实验室备案现状。结果显示:部分省卫生健康主管部门出台有关实验室备案管理办法时间较早,但未及时更新;2020—2023年全国实验室备案率呈逐年上升趋势,同年二级实验室备案率大于一级实验室,实验室备案数量和备案率在地区、隶属系统之间有差异。建议及时更新与完善实验室备案管理办法,加大对需要备案实验室的主管部门法律法规宣贯力度,强化备案工作,健全监管模式,促进实验室网络构建,提高监管水平。

三株鸡传染性支气管炎病毒优势流行毒株全基因组分析及其致病性

为调查研究禽传染性支气管炎病毒(IBV)的流行及优势毒株致病特性,本研究对实验室分离的IBV毒株进行了遗传演化研究和致病性研究,旨在了解我国当下IBV流行毒株基因型、生物学特性以及为新疫苗的研制提供借鉴参考。首先对56株IBV分离毒株S1全长核苷酸序列进行遗传演化分析,从中挑选了MH20、KC和JS96 3株优势基因型毒株进行全基因组测序分析,然后选取毒力较强的JS96毒株进行了SPF鸡致病性试验。结果表明:遗传演化分析结果显示GI-19是我国主要流行毒株,占比约53.57%,同时变异毒不断涌现,GVI(新基因型)明显的流行增多。3株优势基因型分离毒株的全长基因组与QX-like毒株相似性最高,达到97%以上,但与国内外疫苗株、经典毒株的相似性低,仅为77%左右。抗原表位分析同样表明了分离株与疫苗毒株、经典毒株的B细胞抗原表位数量和序列都存在差异。3株分离毒株均可导致SPF鸡胚矮化和致死,其中JS96对1日龄SPF鸡的致病率高于15日龄SPF鸡,1日龄SPF鸡100%死亡率,15日龄SPF鸡出现生长显著迟缓和个别鸡症状明显,发病鸡剖检均可见“花斑肾”。本研究表明,QX-like基因型IBV毒株是现下IBV的主要流行毒株,对低日龄鸡致病性强,易发生基因重组,与疫苗毒株、经典毒株S蛋白相似性低,适配性较差,急需选择合适疫苗及研发新型疫苗,才能控制当下IBV疫病流行,减少养禽业的损失。

病原体多重PCR检测技术研究进展

引起某一症候群传染病病原体种类繁多,且可能存在复合感染,快速、准确地诊断病原体,既可有效预防疾病传播,也可以很好地指导临床用药。多重PCR(multiplex polymerase chain reaction,MPCR)技术,可在一个反应体系中同时检测多个病原体,满足突发公共卫生事件中迅速查明病因需要。根据MPCR产物检测信号的时机不同,MPCR技术可分为PCR反应实时检测、终点检测、反应后检测3种类型。本文主要针对这3种类型的MPCR技术研究进展进行综述,并探讨此类技术的发展方向。