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Objective:To analyze the etiological and epidemiological characteristics of hand, foot and mouth disease (HFMD) in Xi′an from 2019 to 2021, so as to provide evidence for the prevention and control of HFMD.Methods:Stool specimens and anal swabs were collected from patients with HFMD. Enteroviruses (EVs) including enterovirus 71 (EV71), coxsackievirus A16 (CVA16), CVA6 and CVA10 were detected by RT-PCR. Excel 2007 and SPSS18.0 software were used for data collection and statistical analysis, respectively. The epidemiological data of HFMD cases were analyzed by descriptive epidemiology method. The VP1 gene sequence of the representative strain of each CVA6 genotype was downloaded. Phylogenetic trees were constructed using MEGA X software and the genetic characteristics were analyzed.Results:A total of 1 531 HFMD cases were involved and 1 365 were positive for EVs with a positive rate of 89.16%. The detection rates of EV71, CVA16, CVA6, CVA10 and other EVs were 1.31% (20/1 531), 32.46% (497/1 531), 38.47% (589/1 531), 5.09% (78/1 531) and 11.23% (172/1 531), respectively. There were significant differences in the pathogen composition in HFMD cases of different clinical types (χ 2=46.14, P<0.01) and occupations (χ 2=34.65, P<0.01) as well as in different years (χ 2=462.86, P<0.01). The average age was greater in patients with CVA16 infection than in those with CVA6 or CVA10 infection ( F=6.00, P<0.01). In 2019, the HFMD cases were mainly caused by CVA16, while in 2020 and 2021, the main pathogen was CVA6. Enterovirus-positive cases showed a bimodal distribution with the main peak from May to July and the secondary peak from September to November. CVA16 was the predominant pathogen in spring and summer, and CVA6 was the predominant pathogen in autumn. CVA6 was the dominant pathogen in eight districts and counties of Xi′an; CVA16 was the dominant pathogen in six districts and counties; CVA6 and CVA16 co-circulated in one district. The CVA6 isolates belonged to two evolutionary branches of D3a subtype. Conclusions:CVA6 and CVA16 were the prevalent pathogens of HFMD and CVA6 subtype D3a circulated in Xi′an from 2019 to 2021. The pathogen composition of HFMD cases showed obvious differences in population, time and regional distribution.
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Objective:To investigate the molecular epidemiological characteristics and antibiotic resistance of Clostridioides difficile ( Cd) in hospitalized diarrhea patients in a tertiary hospital in Shaanxi Province. Methods:This study collected 425 stool samples of hospitalized diarrhea patients from October 2018 to December 2021 for isolation and identification of Cd. Toxin genes carried by the isolates were detected. Multilocus sequence typing (MLST) was performed to analyze the phylogenetic profile. Antibiotic susceptibility was analyzed by E-test. Results:Forty-nine strains of Cd were isolated from the 425 samples, including 37 strains of toxigenic Cd (75.5%, 37/49). The detection rate of Cd was 14.0% (25/179) in diarrhea patients aged ≥65 years old and 36.4% (4/11) in Nephrology Department. In the 37 toxigenic Cd strains, A -B + CDT -Cd, A + B + CDT -Cd and A + B + CDT +Cd accounted for 18.9% (7/37), 78.4% (29/37) and 2.7% (1/37), respectively. There were 24 ST types, among which ST2, ST3 and ST54 were the predominant types, each accounting for 12.2% (6/49). All strains were sensitive to metronidazole and vancomycin, with a high resistance rate of 93.9% (46/49) to ciprofloxacin and a low resistance rate of 12.2% (6/49) and 10.2% (5/49) to rifampicin and meropenem, respectively. Conclusions:The main type of toxigenic strains was A + B + CDT -. ST2, ST3 and ST54 were the predominant types and the distribution of ST types was scattered. All isolates were sensitive to metronidazole and vancomycin and most of them were resistant to ciprofloxacin.
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【Objective】 To compare the macrolide resistance, molecular characteristics and multilocus antigen sequence typing (MAST) of Bordetella pertussis (Bp) collected from Xi’an and Shanghai so as to provide reference for prevention of pertussis and optimize vaccination strategies. 【Methods】 Erythromycin, azithromycin and clarithromycin susceptibility of clinical isolates collected from Xi’an and Shanghai during 2018 and 2019 were determined by E-test. PCR was used to detect the drug-resistant genes and mutation sites. MAST was employed to do molecular typing for the strains. The differences in macrolide resistance and MAST types between Xi’an and Shanghai were compared. 【Results】 Totally 34 strains from Xi’an and 26 strains from Shanghai were isolated. There were differences between Xi’an and Shanghai in the macrolide resistance (χ2=13.650, P<0.001). The composition ratio of MAST types of pertussis strains was also different between Xi’an and Shanghai (χ2=18.642, P<0.001) in that the prn1/ptxP1/ptxA1/fim3-1/fim2-1 strains dominated in Xi’an, while the prn1/ptxP1/ptxA1/fim3-1/fim2-1 and prn2/ptxP3/ptxA1/fim3-1/fim2-1 were almost half and half in Shanghai. A2047G site mutation was detected in all the macrolide-resistant strains, but not in all sensitive strains. Methylase genes ermA and ermB were detected in some macrolide-resistant strains. No other macrolide-resistant genes were found in resistant strains and no mutation or drug resistance gene was found in all the susceptible strains. 【Conclusion】 Differences existed between Xi’an and Shanghai in the macrolide resistance and MAST types of Bordetella pertussis strains. Further monitoring of Bordetella pertussis in China is required to better understand the resistance and evolution of the pathogen.
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Objective:To investigate the positive rates of 2019-nCoV nucleic acid in different specimens from confirmed COVID-19 cases during hospitalization and after discharge.Methods:Patients with confirmed COVID-19 were enrolled from designated hospitals. Nasal swabs, throat swabs, and specimens of stool, urine and blood were collected during hospitalization. After the patients were discharged, nasal swabs, throat swabs and stool specimens were collected during follow-up. Real-time RT-PCR was used to detect 2019-nCoV nucleic acid.Results:This study involved 25 confirmed COVID-19 cases. During hospitalization, all patients tested positive in both nasal and throat swab 2019-nCoV nucleic acid tests, and nine of them (36.00%) were positive in stool specimen test. Urine and blood specimen test results were all negative. Nasal swabs, throat swabs and stool specimens were collected from each patient 7 d and 14 d after discharge. Two patients (8.00%) tested positive for 2019-nCoV nucleic acid again in nasal and throat swab tests on 7 d, while all stool specimen tests were negative. No 2019-nCoV nucleic acid was detected in nasal swabs, throat swabs or stool samples on 14 d.Conclusions:2019-nCoV nucleic acid was detected in stool samples of confirmed COVID-19 cases during hospitalization. Nasal and throat swab nucleic acid tests turned positive again in some patients after discharge.
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Objective To understand the distribution of novel coronaviruses in the external environment of confirmed COVID-19 cases. Methods Environmental surface swab specimens such as bed rails, doorknob, closestool, hand washing sink, table, locker,ward pager, mobile phone, cup, clothes, were collected from the sentinel hospital of COVID-19, and samples were collected for the nucleic acid detection by RT-PCR. Results A total of 150 environmental samples were collected from 30 confirmed COVID-19 cases, 6 samples were determined to be novel coronaviruses postive (positive rate 4.00%). The total 14 mobile phone showed 3 novel coronaviruses positive.Among the 30 confirmed COVID-19 cases, 6 cases (positive rate 20.00%)were found novel coronaviruses in the external environment. Conclusions Novel coronaviruses exists in external environment of confirmed COVID-19 cases, which indicates the potential risk of COVID-19 infection.
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Objective@#To know the genetic characteristics of nucleoprotein(N)of wild type measles virus in Xi’an, 2013-2017.@*Methods@#We used the pharyngeal swab specimens of suspected measles cases which were tested positive for measles virus (MV) nucleic acid by Real-time RT-PCR to isolate MV strains with Vero-SLAM cells, extracted RNA of the strains, amplified the N genes of MV strains and the pharyngeal swab specimens which had lower Ct values by One-Step RT-PCR, and analyzed the result after sequencing.@*Results@#Thirty carboxyl terminal sequences of the N genes of MV endemic strains were obtained and identified as genotype H1a. The nucleotide and amino acid homology among the epidemic strains were 97.3%-100% and 96.7%-100%, among the epidemic strains and S191 were 91.3%-92.2% and 87.3%-90.0%, while among the epidemic strains and C47 were 92.2%-92.7% and 88.0%-90.7%. The nucleotide homology among the epidemic strains and wild strains of same period in Anhui, Gansu, Shandong, Henan, Jilin were higher than that in Shanxi, Sichuan, Hunan and Guangdong. The most different amino acid sites among the epidemic strains and the two vaccine strains which had high level of entropy were 422, 457 and 497, secondly 467, thirdly 500. The mutations at the 467 site only existed in 2017. dN/dS=0.199 and no positive selection site was found.@*Conclusions@#The dominant genotype of the epidemic MV strains in Xi’an was H1a in 2013-2017, the genetic diversity of viruses decreased in 2016-2017. We should strengthen the surveillance of etiology of MV to provide evidence for elimination of measles.
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Objective@#To analyze the epidemiological characteristics and etiologic agent of herpangina in Xi’an in 2016.@*Methods@#Herpangina epidemiological data and random stool samples were collected from two sentinel hospitals. The data were statistically analyzed with Excel and SPSS 18.0 and samples were detected and enteroviruses were genotyped using real-time PCR and RT-snPCR.@*Results@#Totally 421 cases were reported and the male-to-female ratio was 1.54∶1, age ranged from 3 month to 13 years, and 90.50% were under three years of age. Herpangina showed semiannual peaks in April to October, of which the highest was in June (23.75%, 100/421). Lab result showed that 71.05% were EV positive out of 152 samples, and further genotyping indicated 60 were non-typable, and other 48 comprised of eight serotypes of EV including EV-A71, CV-A4, CV-A5, CV-A6(6.48%), CV-A10(23.15%), CV-A12, CV-A16 and CV-B3.@*Conclusions@#Male children under 3 years of age were the main population and herpangina cases were most frequently reported in June in Xi’an in 2016. CV-A6 and CV-A10 were more frequently detected in the typable ones.
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Objective To describe the vaccine inoculation rate of hemorrhagic fever with renal syndrome (HFRS) and the movement characteristics of rural population in the Xi'an epidemic area.Methods This was a cross-sectional study.The study covered all the four HFRS traditional high incidence areas (counties):Zhouzhi,Huxian,Chang'an and Lintong.Three villages were selected in each county and 20 households were selected in each village in 2013.Participants included all the persons of these families.People 16-60 years old were interviewed face to face about their sociodemographic and environmental information,and at the same time related HFRS vaccine history and characters of migrant workers were collected.Results Nine hundred and ninety-six persons were investigated,69.3 percent (690/996) were vaccinate-age population.Of all,49.0 percent (338/690) had HFRS vaccine history and 53.9 percent (372/690) had worked away from home most of the year.The inoculation proportion of workers which worked in their own counties (56.8％,67/118) were higher than that of workers worked outside (37.0％,60/162;39.1％,36/92,x2 =10.74,6.44,all P ＜ 0.017).In the workers that went back home every week,60.3 percent (76/126) had vaccinated.Workers that went back home once a year had the lowest proportion of inoculation (16.7％,7/42).The morbidity of HFRS decreased significantly accompany with ascend of inoculation rate (Y =-0.524X + 38.319,t =-4.581,P ＜ 0.05).Conclusions After the free vaccinations,there is still a gap between the vaccine inoculation rate and prevention benefit.The current vaccination strategies need to be adjusted.
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Objective To explore the characteristics of intestinal Microbiota in T2DM patients by two molecular fingerprint technologies,and investigate the correlation of intestinal microbiota and T2DM,and evaluate the application value of two fin-gerprint technologies.Methods Fecal samples of 8 healthy groups and 7 diabetes patients were collected.Then the total DNA of gut microbiota was extracted.Through the analysis of products by two molecular fingerprints of ERIC-PCR and DGGE-PCR,ecological characteristics of diversity and similarity of gut microbiota were obtained in healthy groups and dia-betes patients.Results Compared to healthy groups,the number of bands and Shannon-Wiener index of gut microbiota in di-abetes patients was decreased but no statistical significance.The similarity in patients group was declining(P <0.05),and the construction of gut microbiota was inclined to differ.Two fingerprint technologies of ERIC and DGGE could directly re-flect the diversity of gut microbiota and were the modern molecular biological techniques without depending on cultivation. ERIC was simple and convenient,had a better reflection of microbial diversity,but gel band cutting and regarded asa proper approach with higher diffraction efficiency and excellent repetition to studysequencing couldn’t be performed since there were more influencing factors on the experiment.DGGE could better reflect the ecological characteristics such as microbial diversity and similarity,and selecting bands,gel band cutting and sequencing could be done.Conclusion The composition and construction of gut microbiota in diabetes patients were changed,which suggests the occurrence of the disease had the correlation with gut microbiota.ERIC and DGGE is regarded as a proper approach with higher diffraction efficiency and ex-cellent repetition to study intestinal microbiota,but also gel band cutting,sequencing,bacteria identification can be performed by DGGE,both can be used in combination.
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<p><b>OBJECTIVE</b>To investigate the pathogenic and clinical presentation and laboratory tests of bullous rash in hand, foot and mouth disease (HFMD) in Xi'an from January 2013 to December 2014 by retrospective analysis.</p><p><b>METHOD</b>A total of 224 specimens were collected from clinically diagnosed HFMD cases who were characterized by widespread mucocutaneous bullous reactions in Xi'an Children's Hospital from January 2013 to December 2014, the identification and subtyping of the isolates were conducted with real-time fluorescent quantitative RT-PCR. A retrospective analysis was performed to analyze the clinical presentation, laboratory tests and late follow-up problems of the HFMD.</p><p><b>RESULT</b>In the clinically diagnosed HFMD cases who were characterized by widespread mucocutaneous bullous reactions, 207 were caused by coxsackievirus A6 (CA6), accounting for 92. 4% of all cases with bullous, 4 were caused by enterovirus 71 (EV71), accounting for 1.8%, 10 were caused by coxsackievirus A16 (CA16), accounting for 4. 5%; 4 cases were negative for these viruses. In the cases positive for intestinal virus-nucleic acid, 130 were male, 90 were female; male to female ratio was 1. 44: 1, 203 were <5 years old, accounting for 92. 3%. Leukocytosis was found in 75 cases (34. 1%); high-sensitivity C-reactive protein (hsCRP) increased in 200 cases (90. 9%); elevated myocardial enzyme CK-MB was found in 35 cases (15. 9%), alanine aminotransferase increased in 15 cases (6. 8%); 187 cases had fever (85. 0%). None of the cases had serious complications such as encephalitis or myocarditis. In the course of the critical phase bullous rash or large vesicle-like changes, obvious itching, and facial rash appeared. After the fluid in the bullae was absorbed or the bullae ruptured or became ulcerated, scar formation and large areas of exfoliation occurred, with no effusion on the newly formed epithelium in the base, without significant pigmentation on later follow-up. In the late follow up process, 52 cases in CA6-positive patients (25. 1%) developed onychomadesis within 2-4 weeks after onset, 1 to 8 nails, an average of 4. 3 fell off, new nails grew, the nail bed showed no structural abnormalities and hyperplasia after falling off, the surface was smooth, had no hypertrophy, left no sequelae.</p><p><b>CONCLUSION</b>The pathogen in HFMD characterized by widespread bullous reactions was mainly the CA6, this kind of HFMD was mainly mild type, with significant itching, later the bullae may have scar formation and skin exfoliation, in some cases onychomadesis may occur.</p>
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Child , Female , Humans , Male , Enterovirus A, Human , Enterovirus Infections , Pathology , Exanthema , Pathology , Fever , Hand, Foot and Mouth Disease , Pathology , Pruritus , Retrospective StudiesABSTRACT
Objective To screen and identify effective small interfering RNA (siRNAs) targeting the conserved 5’ untrans-lated region (UTR) of the enterovirus 71 (EV71) genome. Methods Double-stranded siRNAs were designed to target the 5’UTR of the EV71 genome. The cytotoxicity effect of siRNAs on rhabdomyosarcoma (RD) cells was evaluated. The cytopathic effect on EV71-infected RD cells was observed under phase-contrast microscopy and the effective siRNAs were screened out by cell viability assay and real-time TaqMan RT-PCR assay. Results All the siRNAs did not exhibit any cytotoxic effects on the viability and growth of RD cells. Transfection of si-1 and si-2 targeting the 5’ UTR in EV71 genome into RD cells signiifcantly delayed and alleviated the cytopathic effects of EV71 infection, increased cell viability and reduced the EV71 RNA transcripts. And the inhibitory effect of si-1/si-2 on EV71 replication was sequence-speciifc. Conclusions The 2 siRNAs (si-1 and si-2) targeting the conserved 5’UTR of the EV71 genome may have broad spectrum antiviral effects on many epidemic EV71 strains.