Integrative Analysis of Salmonellosis in Israel Reveals Association of Salmonella enterica Serovar 9,12:l,v:− with Extraintestinal Infections, Dissemination of Endemic S. enterica Serovar Typhimurium DT104 Biotypes, and Severe Underreporting of Outbreaks

Abstract

f Salmonella enterica is the leading etiologic agent of bacterial food-borne outbreaks worldwide. This ubiquitous species contains more than 2,600 serovars that may differ in their host specificity, clinical manifestations, and epidemiology. To characterize salmonellosis epidemiology in Israel and to study the association of nontyphoidal Salmonella (NTS) serovars with invasive infections, 48,345 Salmonella cases reported and serotyped at the National Salmonella Reference Center between 1995 and 2012 were analyzed. A quasi-Poisson regression was used to identify irregular clusters of illness, and pulsed-field gel electrophoresis in conjunction with whole-genome sequencing was applied to molecularly characterize strains of interest. Three hundred twenty-nine human salmonellosis clusters were identified, representing an annual average of 23 (95% confidence interval [CI], 20 to 26) potential outbreaks. We show that the previously unsequenced S. enterica serovar 9,12:l,v:؊ belongs to the B clade of Salmonella enterica subspecies enterica, and we show its frequent association with extraintestinal infections, compared to other NTS serovars. Furthermore, we identified the dissemination of two prevalent Salmonella enterica serovar Typhimurium DT104 clones in Israel, which are genetically distinct from other global DT104 isolates. Accumulatively, these findings indicate a severe underreporting of Salmonella outbreaks in Israel and provide insights into the epidemiology and genomics of prevalent serovars, responsible for recurring illness.

Comparative genomics of Salmonella enterica serovar Montevideo reveals lineage-specific gene differences that may influence ecological niche association

“…2 ). Clades I and II are also distinguished by the presence of an l -rhamnonate metabolism islet, yfa [ 48 ], that is present in many other NTS serovars, and the putative major facilitator transport system island ydj [ 49, 50 ] ( Fig. 2 ).…”

Increasing incidence of invasive nontyphoidal Salmonella infections in Queensland, Australia, 2007-2016

“…In another Australian states and territories, Salmonella Virchow was second to Salmonella Typhimurium as the most common iNTS pathogen comprising 11% and 13% of all iNTS isolates [ 11 , 12 ]. Salmonella Virchow is rare in the United States [ 28 ] but has emerged as an important pathogen in Europe [ 29 ], and Israel [ 30 – 32 ]. In Australia, Salmonella Virchow has been found in chickens, comprising 3.8% of all chicken NTS isolates; whereas bovine, porcine, and raw meat do not seem to be a common source of this serotype [ 33 ].…”

Same species, different diseases: how and why typhoidal and non-typhoidal Salmonella enterica serovars differ

“…Interestingly, various NTS serovars (e.g., Typhimurium, Dublin, Choleraesuis, 9,12:l,v:-) tend to have more potential to cause extraintestinal infections than others. This implies there is a genetic basis for the emergence iNTS disease; however, these differences are still not understood ( Wilkins and Roberts, 1988 ; Marzel et al, 2014 ). In Sub-Saharan Africa, iNTS is a major cause of bacteremia in adults and children, with an estimated annual incidence of 175–388 cases per 100,000 children and 2000–7500 cases per 100,000 HIV-infected adults.…”