#Antibiotic #resistance in #Salmonella enterica isolated from #dairy #calves in #Uruguay (Braz J Microbiol., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Braz J Microbiol. 2019 Oct 12. doi: 10.1007/s42770-019-00151-w. [Epub ahead of print]

Antibiotic resistance in Salmonella enterica isolated from dairy calves in Uruguay.

Casaux ML1, Caffarena RD1,2, Schild CO1,2, Giannitti F1, Riet-Correa F1, Fraga M3.

Author information: 1 Instituto Nacional de Investigación Agropecuaria (INIA), Plataforma de Investigación en Salud Animal, Estación Experimental INIA La Estanzuela, Ruta 50, km 11.5, 70006, Colonia, Uruguay. 2 Facultad de Veterinaria, Universidad de la República, Montevideo, Uruguay. 3 Instituto Nacional de Investigación Agropecuaria (INIA), Plataforma de Investigación en Salud Animal, Estación Experimental INIA La Estanzuela, Ruta 50, km 11.5, 70006, Colonia, Uruguay. mfraga@inia.org.uy.



Salmonella enterica is an important animal and human pathogen that can cause enteritis and septicaemia in calves. Generally, antibiotics are prescribed for the treatment of salmonellosis in dairy calves. Here, we report the isolation of antibiotic resistant S. enterica serotypes from calves, including multidrug-resistant isolates. A total of 544 faecal samples from live healthy and diarrheic dairy calves from 29 commercial dairy farms and organ samples from 19 deceased calves that succumbed to salmonellosis in 12 commercial dairy farms in Uruguay were processed for selective S. enterica culture. In total, 41 isolates were serotyped, and susceptibility to 14 antibiotics, from 9 classes of compounds, was evaluated by disk-diffusion test. The minimum inhibitory concentration (MIC) was determined by microdilution. Salmonella Typhimurium was the most frequent serotype, followed by S. Dublin and S. Anatum. Whether determined by diffusion assay or microdilution, resistance to tetracycline, streptomycin and ampicillin were the most frequently pattern found. Based on MIC, 5 isolates were resistant to at least one antibiotic, 21 were resistant to 2 antibiotics, and 14 were multidrug-resistant (resistant to at least one antibiotic in 3 different categories of antibiotics). Eleven different resistance patterns were found. Multidrug resistance in S. enterica is a concern for animal and public health not only because of its zoonotic potential but also due to the possibility of transfer resistance determinants to other bacterial genera. This represents the first report of the antibiotic resistance in S. enterica in dairy farms in Uruguay.

KEYWORDS: Antibiotic resistance; Dairy calves; Salmonella Anatum; Salmonella Dublin; Salmonella Typhimurium

PMID: 31606855 DOI: 10.1007/s42770-019-00151-w

Keywords: Antibiotics; Drugs Resistance; Salmonella Typhimurium; Cattle; Salmonellosis; Food Safety; Uruguay.


Linked seasonal #outbreaks of #Salmonella Typhimurium among #passerine #birds, domestic #cats and #humans, #Sweden, 2009 to 2016 (Euro Surveill., abstract)

[Source: Eurosurveillance, full page: (LINK). Abstract, edited.]

Linked seasonal outbreaks of Salmonella Typhimurium among passerine birds, domestic cats and humans, Sweden, 2009 to 2016

Robert Söderlund 1, Cecilia Jernberg 2, Linda Trönnberg 2, Anna Pääjärvi 2, Erik Ågren 1, Elina Lahti 1

Affiliations: 1 National Veterinary Institute, Uppsala, Sweden; 2 Public Health Agency of Sweden, Solna, Sweden

Correspondence:  Robert Söderlund

Citation style for this article: Söderlund Robert, Jernberg Cecilia, Trönnberg Linda, Pääjärvi Anna, Ågren Erik, Lahti Elina. Linked seasonal outbreaks of Salmonella Typhimurium among passerine birds, domestic cats and humans, Sweden, 2009 to 2016. Euro Surveill. 2019;24(34):pii=1900074. https://doi.org/10.2807/1560-7917.ES.2019.24.34.1900074

Received: 24 Jan 2019;   Accepted: 29 Apr 2019



In 2016, an outbreak of Salmonella Typhimurium (STm) with multilocus variable-number tandem repeat analysis (MLVA) profiles historically associated with passerine birds (2-[11-15]-[3-4]-NA-212) occurred among passerines, cats and humans in Sweden. Our retrospective observational study investigated the outbreak and revisited historical data from 2009–16 to identify seasonality, phylogeography and other characteristics of this STm variant. Outbreak isolates were analysed by whole-genome single nucleotide polymorphism (SNP) typing. The number of notified cases of passerine-associated STm among passerines, cats and humans per month and county, and their MLVA profiles, were compared to birdwatchers’ counts of passerines. Seasonal trend decomposition and correlation analysis was performed. Outbreak isolates did not cluster by host on SNP level. Passerine-associated STm was seasonal for birds, cats and humans, with a peak in March. Cases and counts of passerines at bird feeders varied between years. The incidence of passerine-associated STm infections in humans was higher in the boreal north compared with the southern and capital regions, consistent with passerine population densities. Seasonal mass migration of passerines appears to cause STm outbreaks among cats certain years in Sweden, most likely via predation on weakened birds. Outbreaks among humans can follow, presumably caused by contact with cats or environmental contamination.

© This work is licensed under a Creative Commons Attribution 4.0 International License.

Keywords: Wild Birds; Salmonellosis; Cats; Human; Sweden.


Early #dissemination of qnrE1 in #Salmonella Typhimurium from #livestock in South #America (Antimicrob Agents Chemother., abstract)

[Source: Journal of Antimicrobial Chemotherapy, full page: (LINK). Abstract, edited.]

Early dissemination of qnrE1 in Salmonella Typhimurium from livestock in South America

Daniel F. Monte, Nilton Lincopan, Louise Cerdeira, Paula J. Fedorka-Cray, Mariza Landgraf

DOI: 10.1128/AAC.00571-19



The plasmid-mediated quinolone resistance (PMQR) gene qnrE1 has been limited to South America to date and was identified for the first time in Klebsiella pneumoniae from a human infection in Argentina in 2007 (1).…

Copyright © 2019 American Society for Microbiology. All Rights Reserved.

Keywords: Antibiotics; Drugs Resistance; Quinolones; South America; Cattle.


Co-Occurrence of #mcr-1 and qnrS1 on an IncHI2 #Plasmid in #Clinical Isolates of #SalmonellaTyphimurium in #Spain (Vector Borne Zoo Dis., abstract)

[Source: Vector Borne and Zoonotic Diseases, full page: (LINK). Abstract, edited.]

Co-Occurrence of mcr-1 and qnrS1 on an IncHI2 Plasmid in Clinical Isolates of SalmonellaTyphimurium in Spain

Teresa Trujillo-Soto, Jesús Machuca, Jorge Arca-Suárez, Manuel Rodríguez-Iglesias, and Fátima Galán-Sánchez

Published Online: 30 May 2019 / DOI: https://doi.org/10.1089/vbz.2018.2398



Salmonella enterica is a well-adapted zoonotic bacterium associated to cases of gastroenteritis and bacteremia with increased morbidity and mortality. In this study, three isolates of Salmonella Typhimurium obtained from human clinical samples, showing colistin resistance and low-level resistance to quinolones, have been genetically characterized. We detected the co-occurrence of mcr-1 and qnrS1 on a single IncHI2 plasmid in isolates of Salmonella Typhimurium obtained from Spanish children without a travel history. The multiresistant region contained numerous resistance genes. Isolates were clonally related, which suggests the presence of these clones in the community and the potential to cause outbreaks affecting the most susceptible population. It is necessary to monitor the presence of these plasmid-mediated resistance genes in human European strains of Salmonella spp. because of the risk of producing outbreaks of community-acquired infections.

Keywords: Antibiotics; Drugs Resistance; Colistin; Quinolones; Salmonella Typhimurium; Spain.


New #Variant of #MDR #Salmonella enterica Serovar #Typhimurium Associated with Invasive Disease in Immunocompromised Patients in #Vietnam (mBio, abstract)

[Source: mBio, full page: (LINK). Abstract, edited.]

New Variant of Multidrug-Resistant Salmonella enterica Serovar Typhimurium Associated with Invasive Disease in Immunocompromised Patients in Vietnam

Alison E. Mather, Tu Le Thi Phuong, Yunfeng Gao, Simon Clare, Subhankar Mukhopadhyay, David A. Goulding, Nhu Tran Do Hoang, Ha Thanh Tuyen, Nguyen Phu Huong Lan,Corinne N. Thompson, Nguyen Hoang Thu Trang, Juan Carrique-Mas, Ngo Tri Tue, James I. Campbell, Maia A. Rabaa, Duy Pham Thanh, Katherine Harcourt, Ngo Thi Hoa,Nguyen Vinh Trung, Constance Schultsz, Gabriel G. Perron, John E. Coia, Derek J. Brown, Chinyere Okoro, Julian Parkhill, Nicholas R. Thomson, Nguyen Van Vinh Chau, Guy E. Thwaites,Duncan J. Maskell, Gordon Dougan, Linda J. Kenney, Stephen Baker

Philippe J. Sansonetti, Editor

DOI: 10.1128/mBio.01056-18



Nontyphoidal Salmonella (NTS), particularly Salmonella enterica serovar Typhimurium, is among the leading etiologic agents of bacterial enterocolitis globally and a well-characterized cause of invasive disease (iNTS) in sub-Saharan Africa. In contrast, S. Typhimurium is poorly defined in Southeast Asia, a known hot spot for zoonotic disease with a recently described burden of iNTS disease. Here, we aimed to add insight into the epidemiology and potential impact of zoonotic transfer and antimicrobial resistance (AMR) in S. Typhimurium associated with iNTS and enterocolitis in Vietnam. We performed whole-genome sequencing and phylogenetic reconstruction on 85 human (enterocolitis, carriage, and iNTS) and 113 animal S. Typhimurium isolates isolated in Vietnam. We found limited evidence for the zoonotic transmission of S. Typhimurium. However, we describe a chain of events where a pandemic monophasic variant of S. Typhimurium (serovar I:4,[5],12:i:− sequence type 34 [ST34]) has been introduced into Vietnam, reacquired a phase 2 flagellum, and acquired an IncHI2 multidrug-resistant plasmid. Notably, these novel biphasic ST34 S. Typhimurium variants were significantly associated with iNTS in Vietnamese HIV-infected patients. Our study represents the first characterization of novel iNTS organisms isolated outside sub-Saharan Africa and outlines a new pathway for the emergence of alternative Salmonella variants into susceptible human populations.



Salmonella Typhimurium is a major diarrheal pathogen and associated with invasive nontyphoid Salmonella (iNTS) disease in vulnerable populations. We present the first characterization of iNTS organisms in Southeast Asia and describe a different evolutionary trajectory from that of organisms causing iNTS in sub-Saharan Africa. In Vietnam, the globally distributed monophasic variant of Salmonella Typhimurium, the serovar I:4,[5],12:i:− ST34 clone, has reacquired a phase 2 flagellum and gained a multidrug-resistant plasmid to become associated with iNTS disease in HIV-infected patients. We document distinct communities of S. Typhimurium and I:4,[5],12:i:− in animals and humans in Vietnam, despite the greater mixing of these host populations here. These data highlight the importance of whole-genome sequencing surveillance in a One Health context in understanding the evolution and spread of resistant bacterial infections.

Keywords: Antibiotics; Drugs Resistance; Salmonella Typhimurium; HIV/AIDS; Vietnam.