Prevalence, Serotypes, and Antimicrobial Resistance Patterns of Non-Typhoid Salmonella in Food in Northern Taiwan

Abstract

Salmonella is one of the most common bacteria causing food poisoning worldwide. We evaluated the prevalence, the serotypes, and the antimicrobial resistance (AMR) of Salmonella isolates from many kinds of food, particularly pork and chicken in retail, in Taiwan between January 2017 and December 2019. The E-test was used to assess antimicrobial susceptibility and a polymerase chain reaction was performed for serotyping. A total of 459 different foods were investigated, and 117 Salmonella strains were isolated. Retail pork and chicken were the most common Salmonella-contaminated foods (64.1% and 29.1%, respectively). Of the 117 isolates, 23 serotypes were identified. The serotypes Derby (16.2%), Anatum (13.7%), and Agona (8.5%) were the most prevalent. The resistance rates to ciprofloxacin, ceftriaxone, and carbapenem were 41.9%, 11.1%, and 1.7%, respectively. The Derby and Anatum serotypes were prevalent in chicken and pork; the Anatum serotype had significantly higher ciprofloxacin and ceftriaxone resistance rates and was highly prevalent in 2017 and 2018. Multi-locus sequence typing analysis revealed that the 58 randomly chosen Salmonella isolates belonged to 18 sequence types (STs). ST64 (Anatum, 16 out of 58, 27.6%) was the most common, followed by ST321 (Muenster, 6/58, 10.3%), ST831 (Give, 5/58, 8.6%), ST155 (London, 4/58, 6.9%) and ST314 (Kentucky, 4/58, 6.9%). Multidrug-resistant Salmonella strains were remarkably observed in the serotypes Anatum (ST64) and Goldcoast (ST358). This study revealed that retail pork was commonly contaminated with antimicrobial-resistant Salmonella. Thus, periodic investigations of Salmonella serotypes and AMR are needed.

Multidrug-resistant non-typhoidal Salmonella of public health significance recovered from migratory birds in Bangladesh

“…A single S. Brancaster isolate was obtained from migratory birds. This serovar has been associated with human infection in Nigeria ( Ifeanyi et al, 2014 ) and Senegal ( Cardinale et al, 2005 ), and detected in poultry meat in Singapore, Malaysia, and Taiwan ( Chin et al, 2017 ; Zwe et al, 2020 ; Chang et al, 2022 ). Multidrug resistance is common and associated with a core set of AMR genes, which were present in the wild bird isolates, comprising floR (phenicol), qnrS (quinolone), bla TEM-176 (ampicillin), tet (A; tetracycline), dfrA14 (trimethoprim), and aph ( 3′ ) -Ia (aminoglycosides; Chin et al, 2017 , Zwe et al, 2020 ).…”

Comprehensive profiling of serotypes, antimicrobial resistance and virulence of Salmonella isolates from food animals in China, 2015–2021

“…Salmonella , a foodborne pathogen, causes gastroenteritis with severity ranging from diarrheal symptoms to death ( Bae et al, 2013 ). Salmonella is one of the most common pathogens causing foodborne poisoning and is listed as a significant cause of illness and death by the World Health Organization ( Chang et al, 2022 ). To date, approximately 2,600 serotypes have been identified and the majority of them can cause cross-infection between animals and humans ( Raufu et al, 2021 ).…”

Virulence gene profiles and antimicrobial susceptibility of Salmonella Brancaster from chicken

“…For several decades, Salmonella Pullorum and S. Enteritidis are typically the most common serovars with economic impact responsible for Salmonella infection in poultry and humans. However, this predominance has decreased in many regions of the world, where other examples of NTS, such as Salmonella Infantis, Salmonella Derby, and Salmonella Anatum, have become the dominant serovars, reflecting the current situation in many countries [ 8 23 ]. The S. Brancaster in this study were all isolated from healthy chicken flocks with no reported clinical disease or mortality.…”

“…The resistance to ciprofloxacin, a critically important antimicrobial in treating Salmonella infection or typhoid fever in humans, was at 9%, i.e., much higher than those reported by others ranging from 0%–3.8% [ 16 ]. Invasive infections caused by ciprofloxacin-resistant Salmonella have been reported to cause pneumonia, gastroenteritis, fever, septic arthritis, and meningitis in children or immunocompromised adults [ 8 ]. MDR Salmonella has been reported to be more virulent and cause a direct threat to human health when treatment is hampered by resistance [ 30 ].…”

“…In Europe and West Africa, S. Brancaster was isolated from patients with diarrhea and implicated in fatal cases among infants and elderly patients [ 5 6 ]. Few reports indicate that the prevalence of S. Brancaster ranged from 5%–21% in the Asian region, suggesting that S. Brancaster could be an emerging serovar [ 7 8 ].…”