Prevalence and antimicrobial resistance in Salmonella enterica isolated from broiler chickens, pigs and meat products in Thailand–Cambodia border provinces

Abstract

This study aimed to examine the prevalence and antimicrobial resistance (AMR) of Salmonella isolates from broiler chickens, pigs and their associated meat products in the Thailand-Cambodia border provinces. A total of 941 samples were collected from pigs and broiler chickens at slaughter houses and from carcasses at local fresh markets in Sa Kaeo, Thailand (n = 554) and Banteay Meanchey, Cambodia (n = 387) in 2014 and 2015. From these samples, 345 Salmonella isolates were collected from Sa Keao (n = 145; 23%) and Banteay Meanchey (n = 200; 47%) and assayed for antimicrobial susceptibility, class 1 integrons and extended-spectrum β-lactamase (ESBL) genes. Serovars Typhimurium (29%) and Rissen (29%) were the most common serotypes found in Thai and Cambodian isolates, respectively. Multidrug resistance was detected in 34% and 52% of isolates from Sa Keao and Banteay Meanchey, respectively. The majority of the Thai isolates were resistant to ampicillin (72.4%), whereas most Cambodian isolates were resistant to sulfamethoxazole (71%). Eleven isolates from Sa Keao and 44 from Banteay Meanchey carried class 1 integrons comprising resistance gene cassettes. The most common gene cassette array was dfrA12-aadA2 (61.1%). Six isolates were ESBL producers. The β-lactamase genes found included bla , bla and bla . Some of these class 1 integrons and ESBL genes were located on conjugative plasmid. In conclusion, multidrug-resistant Salmonella are common in pigs, chickens and their products in the Thailand-Cambodia border provinces. Our findings indicate that class 1 integrons play a role in spread of AMR in the strains in this study.

Infection, colonization and shedding of Campylobacter and Salmonella in animals and their contribution to human disease: A review

“…Animals infected with and shedding Campylobacter and Salmonella are major sources of meat, milk and egg contamination (Cox et al, 2012;Gast, Guraya, & Guard, 2013;Nollet et al, 2005;Schildt et al, 2006). Isolation of Campylobacter and Salmonella is common in animal-source food products including poultry meat (Anihouvi et al, 2013;Bertasi et al, 2016;Inns et al, 2015;Suzuki & Yamamoto, 2009;Trongjit et al, 2017). As a result, eating raw or undercooked meat especially from poultry (Colette et al, 2018;Doorduyn et al, 2010;WHO, 2012) and drinking unpasteurized milk EFSA, 2015;Studahl & Andersson, 2000;Taylor et al, 2013) are the most important risk factors for human Campylobacter and Salmonella infections of animal origin (Table 1).…”

Antimicrobial resistance in Cambodia: a review

“…In total, seven papers were identified for inclusion of AST data for Salmonella spp., including two studies of isolates from animals and/or their meat products (Lay et al, 2011;Trongjit et al, 2017). Data from the human papers are summarised in Table 3.…”

“…Similar to many other low-and middle-income countries, Cambodia has only relatively recently begun to develop diagnostic microbiological facilities, and, as capacity expands, collaboration has led to sharing of AMR data, revision of clinical practice guidelines, and development of infection control policies (Vlieghe et al, 2013c). In addition, there have been early reports of retrospective and prospective AMR surveillance from nongovernmental hospitals (Fox-Lewis et al, 2018;Vlieghe et al, 2013b), and a handful of studies on animals and/or meat products (Lay et al, 2011;Nadimpalli et al, 2019a;Strom et al, 2018;Trongjit et al, 2017). To date, however, these data have not been brought together to provide a country level perspective.…”

Quantification and rep‐PCR characterization of Salmonella spp. in retail meats and hospital patients in Northern Thailand

“…The prevalence in raw poultry meat in 2014 was 48.7% in Vietnam (Ta et al, ). In the eastern part of Thailand, the Salmonella contamination in chicken was 23% (Trongjit et al, ). The prevalence of Salmonella contamination in pork in Northern Thailand (Chiang Mai and Lamphun) was reported to be 29% (95% CI: 18%–40%) (Padungtod & Kaneene, ), especially in the Chiang Mai old city area where the rate was up to 40% in 2016 (Patchanee et al, ).…”