Abstract
Salmonellosis is a gastrointestinal infection caused by Salmonella enterica and commonly acquired from contaminated food. Worldwide, Salmonellacauses millions of infections and thousands of deaths annually, posing a significant threat to public health. While S. serovars Typhimurium and Enteritidis are the predominant causes of nontyphoidal salmonellosis, Salmonella serovar Schwarzengrund has hitherto been an uncommon cause of human salmonellosis. However, recent reports suggest that this serovar is becoming more prevalent in Asia, Europe and the U.S. A total of 21 strains isolated from different patients from 2006 through 2010 in Switzerland were characterized by (i) assessing phenotypic antibiotic resistance profiles using the disk diffusion method and (ii) by genotyping using pulsed-field gel electrophoresis (PFGE) after macrorestriction with XbaI in order to evaluate strain relationship. The annual incidences from 2006 to 2010 of S. Schwarzengrund varied between 0.11/100’000 in 2006 (highest incidence, 8 cases) and 0.01/100’000 in 2010 (lowest incidence, 1case). All of the isolates were resistant to the sulfonamide antibiotic sulfamethoxazole. Two strains were resistant to the quinolone antimicrobial nalidixic acid as well as to the ß-lactam antibiotic ampicillin and were classified multidrugresistant. Analysis of PFGE data showed high similarity between the strains, as well as similarity to common international clones of S. Schwarzengrund. These findings highlight the need for continued surveillance of occurring genotypes and of antimicrobial resistance in Salmonella spp
Nüesch-Inderbinen, Magdalena