Salmonella enterica has been documented as one of the leading causes of salmonellosis throughout the world and is most commonly associated with the consumption of contaminated food products. Thus, this research was ai...Salmonella enterica has been documented as one of the leading causes of salmonellosis throughout the world and is most commonly associated with the consumption of contaminated food products. Thus, this research was aimed at studying the antimicrobial susceptibility pattern and detection of quinolone resistance in Salmonella spp isolated from food of animal origin. Thirty-six Salmonella isolates comprising 8 from poultry and 28 from seafood（clams） were identified, serotyped and characterized for their antimicrobial susceptibility against 10 different antibiotics. Plasmid DNA was isolated from all the isolates by alkaline lysis, quinolone resistant non-typhoidal S. Weltevreden were examined for mutation in the DNA gyrase coding gene. Among the 36 Salmonella isolates, 20 were S. weltevreden（8 from poultry and 12 from seafood） and 16 were S. Typhimurium（from seafood）. All the isolates showed multiple resistance to nalidixic acid, tetracycline, co-trimoxazole and nitrofurantoin, but, interestingly, the isolates were 100% susceptible to ampicillin, chloramphenicol and gentamicin. Resistant isolates from the study carried the genes responsible for resistance to respective antibiotics. The strain S130 isolated in the study showed single point mutation,Asp87Gly, at position 87 in quinolone resistance determining region. It revealed mutation in quinolone resistance determining region as a cause for quinolone resistance in non-typhoidal Salmonellae. The occurrence of genes accountable for plasmid mediated resistance to quinolones（viz., qnrA, qnrB and qnrS） in plasmid of non-typhoidal Salmonellae isolates provides evidence for plasmid mediated quinolone resistance.展开更多
Non-typhoid Salmonella (NTS) infects 250 to 3200 per 100,000 individuals from all over the world. NTS infection is relatively high in Jeddah (ranges between 44-132/100,000 population) as compared to other cities of Sa...Non-typhoid Salmonella (NTS) infects 250 to 3200 per 100,000 individuals from all over the world. NTS infection is relatively high in Jeddah (ranges between 44-132/100,000 population) as compared to other cities of Saudi Arabia. NTS isolates have also shown increasing resistance to conventional antibiotics. Therefore, fluoroquinolone (FQ) is considered drug of choice for the treatment of invasive NTS infections. A rapid detection of FQ resistance may greatly assist in appropriate therapy and containment of resistant NTS strains. Thus, molecular detection of mutations in FQ resistance genes (gyrA and parC) may play a promising role. Since limited data were available about FQ resistance among NTS isolates, therefore, this study primarily explored the occurrence of phenotypic and genotypic FQ resistance among NTS isolates from Jeddah, Saudi Arabia. Study also explored any correlation between phenotypic and genotypic FQ resistance. Fifty NTS isolates were collected from a public sector hospital of Jeddah from January to December, 2014. FQ susceptibility was determined for 48 NTS isolates using Kirby-bauer disk diffusion method and results were interpreted according to Clinical and Laboratory Standards Institute (CLSI) methodology. Genotypic resistance to FQ was determined by exploring mutations in gyrA and parC genes using PCR- based gene-sequencing method. Results were statistically analyzed using Social Package of Statistical Science (SPSS) version 22. Phenotypic antibiogram revealed that 38% (18/48) NTS isolates were FQ resistant, that 23% (11/48) were intermediately susceptible and that 39% (19/48) were susceptible. Genotypic resistance revealed mutations in only four codons of gyrA and parC genes among 39% (7/18) of FQ resistant isolates. 43% (3/7) of FQ resistant isolates showed mutations at two codons 83 (S83F, S83Y) and 87, (D87G, D87Y, D87W) of gyrA gene. Two resistant isolates showed triple mutations i.e. at codons 83 and 87 of gyrA and codon 80 (S80I and S80W) of parC gene, while one resistant isolate revealed mutation at codon 87 of gyrA and 57 (S57T) of parC gene. Moreover, 55% (6/11) intermediately susceptible isolates for FQ also revealed mutation at codon 83 of gyrA gene whereas;one intermediately susceptible isolate (1/6) also revealed additional mutation at codon 57 of parC gene. None of the FQ susceptible NTS isolates showed any mutations in gyrA or parC genes. Occurrence of mutations at only four codons in gyrA and parC genes among FQ resistant isolates may assist in development of rapid molecular method for FQ resistance detection. Presence of mutations among more than fifty percent of intermediately susceptible FQ isolates is alarming and may serve as a predictor for pre-resistant isolates for FQ. Moreover, absence of mutation in about sixty percent of phenotypically FQ resistant NTS isolates shows existence of an alternate resistance mechanism requiring further investigations.展开更多
Objective:To describe the spanning 25 years data for the occurrence, magnitude, and trends regarding antimicrobial resistance of non-typhoidalSalmonella (NTS) isolated from non-immune travelers to Thailand participati...Objective:To describe the spanning 25 years data for the occurrence, magnitude, and trends regarding antimicrobial resistance of non-typhoidalSalmonella (NTS) isolated from non-immune travelers to Thailand participating in joint military operations.Methods:A total of 355 NTS isolates, obtained from 2052 fecal samples from US soldiers deployed for military maneuvers in Thailand during 1988-2013, were examined for NTS serogroup/serotypes and tested for antimicrobial susceptibility by disk diffusion to these 10 antibiotics:ampicillin, azithromycin (AZM), ciprofloxacin, colistin, gentamicin, kanamycin, nalidixic acid, streptomycin (STR), tetracycline (TET), and trimethoprim/sulfamethoxazole. Identified AZM-resistant NTS isolates were further evaluated for their minimal inhibitory concentration by the E-test method.Results:NTS infections accounted for 17.3％ (355/2052), including 11 serogroups and 50 different serotypes. The most prevalent serogroup wasSalmonella group C2-C3 (35.8％, 127/355) followed by groups B (21.1％, 75/355) and C1 (18.6％, 66/355). Identified serotypes includedSalmonellahadar (n=60),Salmonellarissen (n=45), andSalmonella blockley (n=34). Among the predominate serogroups, antimicrobial resistance was consistently high against TET (76.9％, 273/355) followed by STR (40.8％, 145/355). OneSalmonella senftenberg isolate demonstrated decreased ciprofloxacin susceptibility. Most isolates (94.6％) were resistant to one or more antimicrobials, and the most common multidrug resistance was TET-STR-nalidixic acid (11.5％, 41/355).Conclusions:The prevalence of NTS serotypes and the growing magnitude of antibiotic resistant bacteria isolated from deployed US military in Thailand are documented from 1988-2013. This study demonstrates the antibiotic resistance profiles, highlighting the effectiveness of AZM that is a first-line treatment for travelers to Southeast Asia. AZM-resistant NTS isolates are periodically observed over a 25-year period. Hence, the ongoing surveillance and prevalence efforts are required to monitor NTS resistant strains causing further treatment failure.展开更多
Objective:To describe the spanning 25 years data for the occurrence,magnitude,and trends regarding antimicrobial resistance of non-typhoidal Salmonella(NTS)isolated from non-immune travelers to Thailand participating ...Objective:To describe the spanning 25 years data for the occurrence,magnitude,and trends regarding antimicrobial resistance of non-typhoidal Salmonella(NTS)isolated from non-immune travelers to Thailand participating in joint military operations.Methods:A total of 355 NTS isolates,obtained from 2052 fecal samples from US soldiers deployed for military maneuvers in Thailand during 1988-2013,were examined for NTS serogroup/serotypes and tested for antimicrobial susceptibility by disk diffusion to these 10 antibiotics:ampicillin,azithromycin(AZM),ciprofloxacin,colistin,gentamicin,kanamycin,nalidixic acid,streptomycin(STR),tetracycline(TET),and trimethoprim/sulfamethoxazole.Identified AZM-resistant NTS isolates were further evaluated for their minimal inhibitory concentration by the E-test method.Results:NTS infections accounted for 17.3%(355/2052),including11 serogroups and 50 different serotypes.The most prevalent serogroup was Salmonella group C2-C3(35.8%,127/355)followed by groups B(21.1%,75/355)and C1(18.6%,66/355).Identified serotypes included Salmonella hadar(n=60),Salmonella rissen(n=45),and Salmonella blockley(n=34).Among the predominate serogroups,antimicrobial resistance was consistently high against TET(76.9%,273/355)followed by STR(40.8%,145/355).One Salmonella senftenberg isolate demonstrated decreased ciprofloxacin susceptibility.Most isolates(94.6%)were resistant to one or more antimicrobials,and the most common multidrug resistance was TET-STR-nalidixic acid(11.5%,41/355).Conclusions:The prevalence of NTS serotypes and the growing magnitude of antibiotic resistant bacteria isolated from deployed US military in Thailand are documented from 1988-2013.This study demonstrates the antibiotic resistance profiles,highlighting the effectiveness of AZM that is a first-line treatment for travelers to Southeast Asia.AZM-resistant NTS isolates are periodically observed over a 25-year period.Hence,the ongoing surveillance and prevalence efforts are required to monitor NTS resistant strains causing further treatment failure.展开更多
Objective:To know the current state of non-typhoid Salmonella infection in Laos.To examine the usefulness of new screening methods for Salmonella using citrus.Methods:Non-typhoid Salmonella infection of person in Lao ...Objective:To know the current state of non-typhoid Salmonella infection in Laos.To examine the usefulness of new screening methods for Salmonella using citrus.Methods:Non-typhoid Salmonella infection of person in Lao PDR was studied in this research(2004-2009).The site was Vientiane capital city in 2004.Research from rural villages locating suburb of Vientiane during 2005-2008 was carried out.Rural villages in Attapu province where ethnic minorities were living was searched for this study in 2009.During this research,to detect Salmonella strain, a new method using citrus and citrus extract named MY phenomenon that observing black ring (MIDO ring) on DHL agar was tried.The slice lemon and lime were used for this trial in 2004. After 2005,disk of ascorbic acid and citric acid were used for the device instead of citrus fruits itself.Results:During this research,65 of 272 human samples(23.9%) were infected with non- typhoid Salmonella.Conclusions:During this study,the method using citrus and citrus extracts was accepted for the detection of Salmonella.This study shows that with citrus and citrus extract, detection of Salmonella is possible using only DHL media.Results suggest that infectious rate of non-typhoid Salmonella was high.展开更多
Introduction: The efficacy of chemotherapy in bacteraemia caused by non-typhoidal Salmonella (NTS) is compromised by antibiotic resistance. Objective: This study was undertaken to describe the mechanism of resistance ...Introduction: The efficacy of chemotherapy in bacteraemia caused by non-typhoidal Salmonella (NTS) is compromised by antibiotic resistance. Objective: This study was undertaken to describe the mechanism of resistance among clinical NTS isolates. Materials & Methodology: Thirty of NTS were isolated from blood (n = 19), stool (n = 10) and bronchioalveolar lavage (BAL;n = 1) respectively. These isolates were tested for susceptibility testing by disc diffusion method against ampicillin, gentamicin, tetracycline, co-trimoxazole, nalidixic acid, ciprofloxacin and ceftriaxone. Epsilometer tests (E-test) for nalidixic acid and ciprofloxacin were performed for nalidixic acid resistant isolates by disc diffusion method. DNA sequencing was carried out on six of the nalidixic acid resistant Salmonella Enteritidis isolates to identify mutations within quinolones resistance determining regions (QRDR) of gyrA, gyrB, parC and parE genes. Results: Resistance rates of NTS isolates from blood, stool, and BAL were respectively 37%, 20% and 0% for ampicillin, 79%, 40% and 0% for tetracycline, 32%, 40% and 0% for co-trimoxazole, 37%, 10% and 100% for nalidixic acid. Eight isolates were resistant to nalidixic acid and had exhibited reduced susceptibility towards ciprofloxacin by E-test. Mutation within QRDR was detected in gyrA gene (n = 6;Asp 47 → His [3], Asp 51 → Asn [1], Asp 73 → Gly [1], and Gly 48 → Asp [1]) and double mutation was detected in parE gene (n = 3;Gly 48 → Asp [3], Glu 82 → Ser [3]). Out of six isolates, three isolates were found to have both gyrA and parE gene mutations. Conclusions: There was no mutation observed in gyrB and parC gene. Mutation in gyrA gene was sufficient to induce decreased susceptibility to ciprofloxacin. Variation in amino acid sequences are novel, while detection of other gene mutation was uncommon.展开更多
Purpose: During a large outbreak of Salmonella typhimurium (S. typhimurium) inDenmarkin 2008, a remarkable high incidence was observed among children below the age of 1 year. Therefore we performed this retrospective ...Purpose: During a large outbreak of Salmonella typhimurium (S. typhimurium) inDenmarkin 2008, a remarkable high incidence was observed among children below the age of 1 year. Therefore we performed this retrospective study to describe the epidemiology, severity and outcome among a subset of children in this age-group. Methods: Cases were identified for the years 2000-2009 through a register at the Department of Clinical Microbiology atHvidovreHospital, in theCopenhagenarea,Denmark. For hospitalized patients below 1 year with S. typhimurium, the medical record was reviewed. Results: The highest incidence for S. typhimurium was observed in 2008 with 315 cases per 100,000 among children below 1 year. In 2008 significantly more children age During the S. typhimurium outbreak in 2008, the incidence was especially high among infants age under 1 year. The infants in 2008 might have been slightly more affected than other years 2000-2009.展开更多
Non-pharmaceutical interventions(NPIs)have been proven effective in reducing the spread of the coronavirus disease 2019(COVID-19),but their broader impact on gastrointestinal disorders remains poorly studied.Here,we r...Non-pharmaceutical interventions(NPIs)have been proven effective in reducing the spread of the coronavirus disease 2019(COVID-19),but their broader impact on gastrointestinal disorders remains poorly studied.Here,we report an observational analysis and retrospective study that compares the incidence of acute diarrheal diseases in Hangzhou,Zhejiang,China,between 2019 and 2020,with an examination of the antimicrobial resistance and genetic spectrum of non-typhoidal Salmonella(NTS)from 2015 to 2022,before and during the COVID-19 pandemic.Our findings underscore that NPIs related to COVID-19 effectively reduced the incidence of acute diarrhea,with a substantial decrease in most enteric pathogens.Notably,NTS exhibited an unexpected surge.Further genomic investigations of NTS isolates revealed an overall reduction in antimicrobial-resistant(AMR),disinfection-tolerant,and virulent capabilities,but with marked variations detected between human and animal isolates.Additional genome-based analysis confirmed a decrease in the scale of zoonotic transmission in response to NPIs,suggesting particular NTS types may contribute to human infections via alternative pathways.The collective findings manifested that COVID-19-related NPIs had a mixed impact on NTS infections,which may inform AMR NTS mitigation policy.展开更多
文摘Salmonella enterica has been documented as one of the leading causes of salmonellosis throughout the world and is most commonly associated with the consumption of contaminated food products. Thus, this research was aimed at studying the antimicrobial susceptibility pattern and detection of quinolone resistance in Salmonella spp isolated from food of animal origin. Thirty-six Salmonella isolates comprising 8 from poultry and 28 from seafood（clams） were identified, serotyped and characterized for their antimicrobial susceptibility against 10 different antibiotics. Plasmid DNA was isolated from all the isolates by alkaline lysis, quinolone resistant non-typhoidal S. Weltevreden were examined for mutation in the DNA gyrase coding gene. Among the 36 Salmonella isolates, 20 were S. weltevreden（8 from poultry and 12 from seafood） and 16 were S. Typhimurium（from seafood）. All the isolates showed multiple resistance to nalidixic acid, tetracycline, co-trimoxazole and nitrofurantoin, but, interestingly, the isolates were 100% susceptible to ampicillin, chloramphenicol and gentamicin. Resistant isolates from the study carried the genes responsible for resistance to respective antibiotics. The strain S130 isolated in the study showed single point mutation,Asp87Gly, at position 87 in quinolone resistance determining region. It revealed mutation in quinolone resistance determining region as a cause for quinolone resistance in non-typhoidal Salmonellae. The occurrence of genes accountable for plasmid mediated resistance to quinolones（viz., qnrA, qnrB and qnrS） in plasmid of non-typhoidal Salmonellae isolates provides evidence for plasmid mediated quinolone resistance.
文摘Non-typhoid Salmonella (NTS) infects 250 to 3200 per 100,000 individuals from all over the world. NTS infection is relatively high in Jeddah (ranges between 44-132/100,000 population) as compared to other cities of Saudi Arabia. NTS isolates have also shown increasing resistance to conventional antibiotics. Therefore, fluoroquinolone (FQ) is considered drug of choice for the treatment of invasive NTS infections. A rapid detection of FQ resistance may greatly assist in appropriate therapy and containment of resistant NTS strains. Thus, molecular detection of mutations in FQ resistance genes (gyrA and parC) may play a promising role. Since limited data were available about FQ resistance among NTS isolates, therefore, this study primarily explored the occurrence of phenotypic and genotypic FQ resistance among NTS isolates from Jeddah, Saudi Arabia. Study also explored any correlation between phenotypic and genotypic FQ resistance. Fifty NTS isolates were collected from a public sector hospital of Jeddah from January to December, 2014. FQ susceptibility was determined for 48 NTS isolates using Kirby-bauer disk diffusion method and results were interpreted according to Clinical and Laboratory Standards Institute (CLSI) methodology. Genotypic resistance to FQ was determined by exploring mutations in gyrA and parC genes using PCR- based gene-sequencing method. Results were statistically analyzed using Social Package of Statistical Science (SPSS) version 22. Phenotypic antibiogram revealed that 38% (18/48) NTS isolates were FQ resistant, that 23% (11/48) were intermediately susceptible and that 39% (19/48) were susceptible. Genotypic resistance revealed mutations in only four codons of gyrA and parC genes among 39% (7/18) of FQ resistant isolates. 43% (3/7) of FQ resistant isolates showed mutations at two codons 83 (S83F, S83Y) and 87, (D87G, D87Y, D87W) of gyrA gene. Two resistant isolates showed triple mutations i.e. at codons 83 and 87 of gyrA and codon 80 (S80I and S80W) of parC gene, while one resistant isolate revealed mutation at codon 87 of gyrA and 57 (S57T) of parC gene. Moreover, 55% (6/11) intermediately susceptible isolates for FQ also revealed mutation at codon 83 of gyrA gene whereas;one intermediately susceptible isolate (1/6) also revealed additional mutation at codon 57 of parC gene. None of the FQ susceptible NTS isolates showed any mutations in gyrA or parC genes. Occurrence of mutations at only four codons in gyrA and parC genes among FQ resistant isolates may assist in development of rapid molecular method for FQ resistance detection. Presence of mutations among more than fifty percent of intermediately susceptible FQ isolates is alarming and may serve as a predictor for pre-resistant isolates for FQ. Moreover, absence of mutation in about sixty percent of phenotypically FQ resistant NTS isolates shows existence of an alternate resistance mechanism requiring further investigations.
基金supported by the Armed Forces Health Surveillance Branch and its Global Emerging Infectious Disease Surveillance and Response SectionFunding of this project was partially provided by the U.S.Army Medical and Material Command
文摘Objective:To describe the spanning 25 years data for the occurrence, magnitude, and trends regarding antimicrobial resistance of non-typhoidalSalmonella (NTS) isolated from non-immune travelers to Thailand participating in joint military operations.Methods:A total of 355 NTS isolates, obtained from 2052 fecal samples from US soldiers deployed for military maneuvers in Thailand during 1988-2013, were examined for NTS serogroup/serotypes and tested for antimicrobial susceptibility by disk diffusion to these 10 antibiotics:ampicillin, azithromycin (AZM), ciprofloxacin, colistin, gentamicin, kanamycin, nalidixic acid, streptomycin (STR), tetracycline (TET), and trimethoprim/sulfamethoxazole. Identified AZM-resistant NTS isolates were further evaluated for their minimal inhibitory concentration by the E-test method.Results:NTS infections accounted for 17.3％ (355/2052), including 11 serogroups and 50 different serotypes. The most prevalent serogroup wasSalmonella group C2-C3 (35.8％, 127/355) followed by groups B (21.1％, 75/355) and C1 (18.6％, 66/355). Identified serotypes includedSalmonellahadar (n=60),Salmonellarissen (n=45), andSalmonella blockley (n=34). Among the predominate serogroups, antimicrobial resistance was consistently high against TET (76.9％, 273/355) followed by STR (40.8％, 145/355). OneSalmonella senftenberg isolate demonstrated decreased ciprofloxacin susceptibility. Most isolates (94.6％) were resistant to one or more antimicrobials, and the most common multidrug resistance was TET-STR-nalidixic acid (11.5％, 41/355).Conclusions:The prevalence of NTS serotypes and the growing magnitude of antibiotic resistant bacteria isolated from deployed US military in Thailand are documented from 1988-2013. This study demonstrates the antibiotic resistance profiles, highlighting the effectiveness of AZM that is a first-line treatment for travelers to Southeast Asia. AZM-resistant NTS isolates are periodically observed over a 25-year period. Hence, the ongoing surveillance and prevalence efforts are required to monitor NTS resistant strains causing further treatment failure.
基金supported by the Armed Forces Health Surveillance Branch and its Global Emerging Infectious Disease Surveillance and Response SectionFunding of this project was partially provided by the U.S.Army Medical and Material Command
文摘Objective:To describe the spanning 25 years data for the occurrence,magnitude,and trends regarding antimicrobial resistance of non-typhoidal Salmonella(NTS)isolated from non-immune travelers to Thailand participating in joint military operations.Methods:A total of 355 NTS isolates,obtained from 2052 fecal samples from US soldiers deployed for military maneuvers in Thailand during 1988-2013,were examined for NTS serogroup/serotypes and tested for antimicrobial susceptibility by disk diffusion to these 10 antibiotics:ampicillin,azithromycin(AZM),ciprofloxacin,colistin,gentamicin,kanamycin,nalidixic acid,streptomycin(STR),tetracycline(TET),and trimethoprim/sulfamethoxazole.Identified AZM-resistant NTS isolates were further evaluated for their minimal inhibitory concentration by the E-test method.Results:NTS infections accounted for 17.3%(355/2052),including11 serogroups and 50 different serotypes.The most prevalent serogroup was Salmonella group C2-C3(35.8%,127/355)followed by groups B(21.1%,75/355)and C1(18.6%,66/355).Identified serotypes included Salmonella hadar(n=60),Salmonella rissen(n=45),and Salmonella blockley(n=34).Among the predominate serogroups,antimicrobial resistance was consistently high against TET(76.9%,273/355)followed by STR(40.8%,145/355).One Salmonella senftenberg isolate demonstrated decreased ciprofloxacin susceptibility.Most isolates(94.6%)were resistant to one or more antimicrobials,and the most common multidrug resistance was TET-STR-nalidixic acid(11.5%,41/355).Conclusions:The prevalence of NTS serotypes and the growing magnitude of antibiotic resistant bacteria isolated from deployed US military in Thailand are documented from 1988-2013.This study demonstrates the antibiotic resistance profiles,highlighting the effectiveness of AZM that is a first-line treatment for travelers to Southeast Asia.AZM-resistant NTS isolates are periodically observed over a 25-year period.Hence,the ongoing surveillance and prevalence efforts are required to monitor NTS resistant strains causing further treatment failure.
基金supported by 'The development and practical use of a device for the simple detection method of Salmonella by a citrus fruit extraction(Issue number 18650222 2006-2008)''Elucidaation of mechanism and dissemination of new detection methods by using citrus extracts for food poisoning bacteria such as Salmonella (Issue number 22500783 2010-2012)' 'International Cooperation Research concerning water-borne diseases in relocated people and the development of related risk management techniques(Issue number 2256003 0001 2010- 2012)' grant aid of Japanese Ministry of Education,Culture. Sports,Science and Technology
文摘Objective:To know the current state of non-typhoid Salmonella infection in Laos.To examine the usefulness of new screening methods for Salmonella using citrus.Methods:Non-typhoid Salmonella infection of person in Lao PDR was studied in this research(2004-2009).The site was Vientiane capital city in 2004.Research from rural villages locating suburb of Vientiane during 2005-2008 was carried out.Rural villages in Attapu province where ethnic minorities were living was searched for this study in 2009.During this research,to detect Salmonella strain, a new method using citrus and citrus extract named MY phenomenon that observing black ring (MIDO ring) on DHL agar was tried.The slice lemon and lime were used for this trial in 2004. After 2005,disk of ascorbic acid and citric acid were used for the device instead of citrus fruits itself.Results:During this research,65 of 272 human samples(23.9%) were infected with non- typhoid Salmonella.Conclusions:During this study,the method using citrus and citrus extracts was accepted for the detection of Salmonella.This study shows that with citrus and citrus extract, detection of Salmonella is possible using only DHL media.Results suggest that infectious rate of non-typhoid Salmonella was high.
文摘Introduction: The efficacy of chemotherapy in bacteraemia caused by non-typhoidal Salmonella (NTS) is compromised by antibiotic resistance. Objective: This study was undertaken to describe the mechanism of resistance among clinical NTS isolates. Materials & Methodology: Thirty of NTS were isolated from blood (n = 19), stool (n = 10) and bronchioalveolar lavage (BAL;n = 1) respectively. These isolates were tested for susceptibility testing by disc diffusion method against ampicillin, gentamicin, tetracycline, co-trimoxazole, nalidixic acid, ciprofloxacin and ceftriaxone. Epsilometer tests (E-test) for nalidixic acid and ciprofloxacin were performed for nalidixic acid resistant isolates by disc diffusion method. DNA sequencing was carried out on six of the nalidixic acid resistant Salmonella Enteritidis isolates to identify mutations within quinolones resistance determining regions (QRDR) of gyrA, gyrB, parC and parE genes. Results: Resistance rates of NTS isolates from blood, stool, and BAL were respectively 37%, 20% and 0% for ampicillin, 79%, 40% and 0% for tetracycline, 32%, 40% and 0% for co-trimoxazole, 37%, 10% and 100% for nalidixic acid. Eight isolates were resistant to nalidixic acid and had exhibited reduced susceptibility towards ciprofloxacin by E-test. Mutation within QRDR was detected in gyrA gene (n = 6;Asp 47 → His [3], Asp 51 → Asn [1], Asp 73 → Gly [1], and Gly 48 → Asp [1]) and double mutation was detected in parE gene (n = 3;Gly 48 → Asp [3], Glu 82 → Ser [3]). Out of six isolates, three isolates were found to have both gyrA and parE gene mutations. Conclusions: There was no mutation observed in gyrB and parC gene. Mutation in gyrA gene was sufficient to induce decreased susceptibility to ciprofloxacin. Variation in amino acid sequences are novel, while detection of other gene mutation was uncommon.
文摘Purpose: During a large outbreak of Salmonella typhimurium (S. typhimurium) inDenmarkin 2008, a remarkable high incidence was observed among children below the age of 1 year. Therefore we performed this retrospective study to describe the epidemiology, severity and outcome among a subset of children in this age-group. Methods: Cases were identified for the years 2000-2009 through a register at the Department of Clinical Microbiology atHvidovreHospital, in theCopenhagenarea,Denmark. For hospitalized patients below 1 year with S. typhimurium, the medical record was reviewed. Results: The highest incidence for S. typhimurium was observed in 2008 with 315 cases per 100,000 among children below 1 year. In 2008 significantly more children age During the S. typhimurium outbreak in 2008, the incidence was especially high among infants age under 1 year. The infants in 2008 might have been slightly more affected than other years 2000-2009.
基金We would like to thank Annemieke van den Dool(Duke Kunshan University)for the critical reading of the manuscriptThis study was supported by the National Program on the Key Research Project of China(2022YFC2604201)+4 种基金the European Union’s Horizon 2020 Research and Innovation Programme(861917-SAFFI)Zhejiang Provincial Key R&D Program of China(2023C030452022C02024)Zhejiang Provincial Naturaal Science Foundation of China(LZ24C180002)Hainan Provincial Joint Project of Sanya Yazhou Bay Science and Techonology City(2021JJLH0083).
文摘Non-pharmaceutical interventions(NPIs)have been proven effective in reducing the spread of the coronavirus disease 2019(COVID-19),but their broader impact on gastrointestinal disorders remains poorly studied.Here,we report an observational analysis and retrospective study that compares the incidence of acute diarrheal diseases in Hangzhou,Zhejiang,China,between 2019 and 2020,with an examination of the antimicrobial resistance and genetic spectrum of non-typhoidal Salmonella(NTS)from 2015 to 2022,before and during the COVID-19 pandemic.Our findings underscore that NPIs related to COVID-19 effectively reduced the incidence of acute diarrhea,with a substantial decrease in most enteric pathogens.Notably,NTS exhibited an unexpected surge.Further genomic investigations of NTS isolates revealed an overall reduction in antimicrobial-resistant(AMR),disinfection-tolerant,and virulent capabilities,but with marked variations detected between human and animal isolates.Additional genome-based analysis confirmed a decrease in the scale of zoonotic transmission in response to NPIs,suggesting particular NTS types may contribute to human infections via alternative pathways.The collective findings manifested that COVID-19-related NPIs had a mixed impact on NTS infections,which may inform AMR NTS mitigation policy.
