Characterization of Antimicrobial Resistance inSalmonella entericaIsolated from Pork, Chicken Meat, and Humans in Northeastern Thailand

Abstract

A total of 221 Salmonella enterica from raw pork (n=64), raw chicken (n=80), and humans (n=77) were characterized for antimicrobial resistance phenotypes and genotypes and virulence plasmid-associated genes. Most Salmonella isolates (95.9%) were multidrug resistant and exhibited high resistance to sulfamethoxazole (96.4%), streptomycin (93.2%), spectinomycin (76.5%), tetracycline (73.3%), ampicillin (70.1%), and trimethoprim (60.2%). Forty-one percent of all isolates were intI1-positive, of which 60% carried class 1 integrons with variable region ranging in size from 0.2 to 2.0 kb. Six integron profiles (IP-I to IP-VI) were defined. The dfrA12-aadA2 cassette was most prevalent (66.7%). Class 1 integrons with the dfrA12-aadA2 cassette in five pork isolates could be horizontally transferred. Three pork isolates carried Salmonella genomic island 1 (SGI1), of which a serovar Anatum harbored SGI1 gene cluster located between thdF and int2. Two single-point mutations (i.e., G-259-T and C-248-T) in gyrA leading to Asp-87-Tyr and Ser-83-Phe substitutions in GyrA, respectively, were detected. Of all plasmid-mediated quinolone resistance genes tested, only qnrS (4.1%) and qnrB (1.8%) were found. The virulence plasmid-associated genes including spvC, pefA, and rck were identified in 8.1%, 1.8%, and 1.4% of all Salmonella isolates, respectively.

Occurrence and Antimicrobial Susceptibility Profile ofSalmonellaspp. in Raw and Ready-To-Eat Foods andCampylobacterspp. in Retail Raw Chicken Meat in Transylvania, Romania

“…Similar to our results, increasing AMR trends were published for TET in China [87.5% (Ren et al, 2017); 75.3% (Zhang et al, 2018)], Thailand [73.3% (Sinwat et al, 2015)], North Vietnam [58.5% (Thai et al, 2012)] and the Czech Republic [100% (Myšková and Karpišková, 2017)]; for SMX in Thailand (Sinwat et al, 2015) and Latvia (Terentjeva et al, 2017); for CIP in Latvia [24.0% (Terentjeva et al, 2017)]; and for NAL in North Vietnam [28.8% (Thai et al, 2012)]. Even if the recorded resistance level to another seven antibiotics, including AMP (35.3%), CHL (33.3%), TGC (25.5%), CTX (13.7%), CST (13.7%), TMP (7.8%), and GEN (2%) were moderate or low, the obtained results underscored a wide and worrying resistance spectrum of the Salmonella strains.…”

Antimicrobial Resistance Profile andmcr-1Gene Detection inSalmonellaIsolates from Poultry in Bangladesh: Molecular and Bioinformatics Characterization

“…These antimicrobials resistance against Salmonella isolates might designate the over use or abuse of these antibiotics (14, 15, 58). On the other hand, Salmonella isolates found to be susceptible to ceftriaxone, fosfomycin, neomycin, levofloxacin, norfloxacin and azithromycin which is in line with previous reports (64, 66). It may be because; these antibiotics are not commonly used for therapeutic purposes in veterinary medicine..…”

High prevalence and molecular characteristics of multidrug-resistant Salmonella in pigs, pork and humans in Thailand and Laos provinces

“…One interpretation of these data is that cephalosporins are cost prohibitive for most family-owned Laotian pig farms and the drugs are less often used, thereby limiting the selection pressure for resistance genes (Boonmar et al, 2008). In addition, gentamicin resistance in Thai isolates was higher than previous reports in pork from the same country (Angkititrakul et al, 2005;Sinwat et al, 2015) but more similar to that in Vietnam . In contrast, almost all the Laos isolates were susceptible to gentamicin.…”