Paediatric Salmonellosis—Differences between Tropical and Sub-Tropical Regions of Queensland, Australia

Salmonellosis is an important cause of morbidity in tropical regions.This study aims to describe the epidemiology of non-typhoidal Salmonellae (NTS) in children presenting to public hospitals in Queensland, Australia, over the past 20 years, with a focus on differences between tropical and sub-tropical zones in the region. This is a retrospective and descriptive cohort study of 8162 NTS positive samples collected in 0–17-year-olds from the Queensland public hospital pathology database (Auslab) over a 20-year period from 1997 to 2016. There were 2951 (36.2%) positive NTS samples collected in tropical zones and 5211 (63.8%) in the sub-tropical zones of Queensland, with a total of 8162 over the region. The tropical zone contributed a disproportionately higher number of positive NTS samples by population sub-analysis. Of the specimens collected, 7421 (90.92%) were faecal, 505 (6.2%) blood, 161 (1.97%) urine, 13 (0.16%) cerebrospinal fluid (CSF) and 62 of other origin. Other categories of specimen types isolated include swab, fluid, aspirate, lavage, bone, tissue, isolate and pus, and these were not included in sub-analysis. The most commonly identified serovars were Salmonella Typhimurium, Salmonella Virchow and Salmonella Saintpaul. This is the first and largest study that emphasises the high burden of invasive and non-invasive NTS infections resulting in hospital presentations in the paediatric population of tropical north Queensland, compared to the sub-tropics.

Influence of lactic acid on the survival of Salmonella on poultry carcass surfaces

The aim of this study was to determine the influence of Salmonella by different lactic acid concentrations in microbiological media and on the surfaces of the chicken carcasses. Contamination of samples were used strains: Salmonella Enteritidis, Salmonella Typhimurium , Salmonella Hadar, Salmonella Infantis and Salmonella Virchow. Each strain from each dilution was placed on nutrient agar without the addition of chemical substances (the control), and on nutrient agar with various amounts of substances added 0,02%, 0,05%, 0,1%, 0,25%, 0,5%, 1%, 2% solutions of lactic acid. A concentration of up to 0.02% of lactic acid did not have a significant effect on the quantitative growth of Salmonella spp. .Lactic acid, starting from the con-centration of 0.1 %, completely inhibits growth of all the studied strains of Salmonella. 150 samples from broiler chicken breasts, was immersed for 2 minutes in 80 ml of Salmonella suspension containing 107 CFU. The sam-ples were then transferred to sterile beakers with 250 ml of 2% and 5% solutions of lactic acid for a period of 5 minutes. At a lactic acid concentration of 2%, the number of Salmonella, compared to the control, reductions ranging from 0,18 to 1,21 log. At the lactic acid concentration of 5%, the number of Salmonella, compared to the control, reductions ranging for from 2,69 log to 3,67 log. .

Incidence, Antimicrobial Resistance, and Molecular Characteristics of Nontyphoidal Salmonella Including Extended-Spectrum β-Lactamase Producers in Retail Chicken Meat

The present study was undertaken to determine the prevalence of Salmonella in 100 chicken carcass samples from five integrated broiler operation brands in Korea. Serotypes, antibiotic resistance patterns, extended-spectrum β-lactamase (ESBL) genotype, and clonal divergence using multilocus sequence typing of the isolated strains were analyzed. A total of 42 chicken samples were contaminated with nontyphoidal Salmonella (NTS) isolates: 16 isolates (38%) were Salmonella Virchow, 9 (21%) were Salmonella Bareilly, and 8 (19%) were Salmonella Infantis. A multidrug resistance (MDR; resistant to more than three classes of antibiotics) phenotype was observed in 29% of the isolates, which were resistant to five or more classes of antibiotics. The dominant MDR type was resistance to classes of penicillin, cephalosporins, aminoglycosides, quinolones, and tetracyclines. All the MDR isolates were positive for ESBL producers, and all but one (with the CTX-M-1 genotype) had the CTX-M-15 genotype. Multilocus sequence typing of the isolates revealed ST16 as the dominant sequence type; Salmonella Virchow, Salmonella Infantis, and Salmonella Richmond were all ST16, indicating a close genetic relationship between these serovars. This is the first study in Korea showing the CTX-M-1 type of NTS and the prevalence of ESBL-producing strains among NTS isolated from retail chicken meat. Our findings suggest that MDR Salmonella contamination is widely prevalent in retail chicken meat, and consumption of inadequately cooked products could lead to dissemination of NTS, which is hazardous to human health.

Outbreak of salmonellosis in a restaurant in Stockholm, Sweden, September – October 2006

The largest outbreak of salmonellosis in 25 years in Stockholm County occurred during September - October 2006. A total of 115 persons who had a meal at a restaurant in Stockholm were notified as cases of salmonellosis through the Swedish surveillance system. The probable vehicle of the outbreak was mung beans, soaked in lukewarm water for 24 hours before being served at the restaurant. These mung beans had been included in all dishes served in the restaurant and the outbreak was terminated when they were excluded from the menu. Either Salmonella Bareilly or Salmonella Virchow were isolated from affected persons. No person was found to have an infection with both serotypes. The majority of affected persons were females with a median age of 34 years.This and similar outbreaks associated with consumption of vegetables and fruits highlight the increasing importance of fresh produce as vehicle for foodborne outbreaks in Europe.