Investigation of Class I Integron in Salmonella infantis and Its Association With Drug Resistance

Abstract

Background:Infection with non-typhoid Salmonella (NTS) is one of the most important health problems all over the world. Antimicrobial drug resistance is increasing among Salmonella infantis species.Objectives:The aim of this study was to investigate the frequency of presence of class 1 integrons in S. infantis species as well as its association with drug resistance.Materials and Methods:This cross-sectional study was performed on 50 S. infantis isolated strains, collected from chicken samples between 2009-2011. These strains were identified by standard biochemical tests and serology. Antibiotic susceptibility profiles and minimum inhibitory concentration determination for 14 antibacterial agents were performed using micro dilution and disk diffusion methods. The detection of class 1 integron was performed by the PCR method. The demographic and microbiological data for the integron positive and negative isolates were compared by SPSS software.Results:Eighteen out of 50 (36%) of isolated S. infantis species had intl gene. The isolated bacteria were sensitive to cefotaxime and ciprofloxacin (100%). Also isolates were resistant to nalidixic acid, tetracycline and streptomycin. All isolate with class 1 integron were multidrug resistant.Conclusions:The result of this study showed that due to increased level of drug resistance in S. infantis and the presence of class 1 integron in these strains, resistance can be transferred to other food borne pathogens.

Distribution of Class 1 and 2 Integrons Among Salmonella Enterica Serovars Isolated from Iranian Patients

“…In the present study, we characterized two classes of integrons, and 45 out of 138 isolates harbored class 1 (17.3%) and class 2 (15.2%) integrons. In a previous study, Asgharpour et al showed that 36% of S. infantis isolates were positive for class 1 integrons, and all these isolates were also resistant to nalidixic acid, tetracycline, and streptomycin [19]. In comparison with our study, the higher prevalence of class 1 integrons in the mentioned study shows that application of antibiotics in the poultry industry may increase antibiotic resistance [20].…”

Antibiotic Susceptibility and Molecular Screening of Class I Integron in Salmonella Isolates Recovered from Retail Raw Chicken Carcasses in China

“…33,34 This study presented that 92.92% of the class I integron-positive isolates were resistant to at least two antibiotics, and this exhibited a good evidence for the relationship between the presence of class I integron and the emerging of MDR in gram-negative bacteria. 12,29 Integron, a mobile DNA element, is known to contain one or more linked antimicrobial resistance genes and can transfer these genes among bacteria. 35,36 In this study, PCR analysis showed that 113 (15.21%) of 743 Salmonella isolates were carrying class I integron.…”

“…10,11 Several previous foodborne outbreaks indicated that the multidrug-resistant (MDR) Salmonella was of increasing concern. [12][13][14][15] Integrons are mobile DNA elements comprising a sitespecific recombination system that is capable of integrating and expressing antibiotic resistance genes in cassette-like structures and transferring resistant genes from one bacterium to another, which in turn lead to the emergence of antibiotic resistance. 15,16 Among various integrons, class I integron was the most predominant one and played a major role in multidrug resistance development of Salmonella.…”

“…[17][18][19][20] Several previous studies indicated that class I integrons could be detected in MDR Salmonella from animals, eggs, poultry, human, pork, retail beef, and chicken carcasses in Japan, the United States, Iran, Ethiopia, Taiwan, Brazil, and China. 8,12,16,17,[19][20][21][22] However, information regarding the distribution of antimicrobial resistance-associated integron in Salmonella among retail foods is still not well documented. In this study, the prevalence of class I integron and antibiotic resistance-associated gene cassettes in Salmonella isolates were determined for better understanding class I integron distribution in Salmonella isolates recovered from retail chicken carcasses in China.…”

A novel subpopulation of Salmonella enterica serovar Infantis strains isolated from broiler chicken organs other than the gastrointestinal tract

“…Nó grá dy et al (2012) investigated S. Infantis strains collected in European countries and showed that 33 out of 76 strains were multi-drug resistant and carried a class I integron on a large plasmid. Asgharpour et al (2014) reported that 18 of 50 S. Infantis strains isolated in Iran were multi-drug resistant and carried a class I integron. These features were similar to those reported by Aviv et al (2013), suggesting possible worldwide dissemination of S. Infantis strains carrying the mega plasmid.…”