Occurrence of virulence factors and carbapenemase genes in Salmonella enterica serovar Enteritidis isolated from chicken meat and egg samples in Iraq

Abstract

Background Food-borne infections mainly due to Salmonella enterica serovar Enteritidis (S. Enteritidis) are major concerns worldwide. S. Enteritidis isolates may serve as reservoirs for spreading antimicrobial drug resistance genes including carbapenemases. This study aimed to screen the occurrence of virulence factors, carbapenemases, and antibiotic resistance genes in S. Enteritidis isolated from chicken meat and eggs in Iraq. Results In total, 1000 non-duplicated chicken meat and 1000 egg samples were collected during 2019–2020. Presumptive S. Enteritidis isolates were initially identified by standard bacteriology tests and then were confirmed using polymerase chain reaction (PCR). Carbapenem resistance was detected using the disk diffusion method. Virulence and carbapenemase genes were screened using the PCR method. In total, 100 (5.0%) S. Enteritidis isolates were identified from 2000 samples collected using phenotypic and molecular methods. These isolates were identified from 4.9% chicken meat (n = 49/1000) and 5.1% egg (n = 51/1000) samples, respectively. The most and the least susceptibility was found to gentamicin and ceftazidime antibiotics, respectively. The prevalence of different virulence factors were as follows: phoP/Q (40.0%), traT (30.0%), stn (22.0%), slyA (11.0%), and sopB (9.0%). Among 20 carbapenem-resistant S. Enteritidis isolates, the most predominant carbapenemase gene was blaIMP (35.0%, n = 7), followed by blaOXA−48−like (25.0%, n = 5), and blaNDM (10.0%, n = 2), while the blaKPC and blaVIM genes were not detected. The coexistence of blaIMP, blaOXA−48−like, and blaNDM genes was determined in two isolates. The prevalence of different antibiotic resistance genes were as follows: tetA (87.1%), tetB (87.1%), dfrA1 (77.6%), and sul1 (83.6%). Conclusion Considering the existence of carbapenem-resistant S. Enteritidis harboring different virulence and antibiotic resistance genes in chicken meat and egg samples, adherence to proper hygienic conditions should be considered.

The emergence of carbapenem-resistance and New Delhi metallo-β-lactamase-1 (bla NDM-1 ) among Salmonella spp. in Kerman, Iran

“…In this study, the prevalence of resistance to amikacin and ciprofloxacin were considerably high. This results is consistent with previous studies on chicken meat conducted in Egypt and Iraq ( 27 , 28 ). The reporting of resistance to antibiotic agents in Salmonella isolates from fecal samples of chicken farms suggests the contamination and spread of resistant strains in the environment, posing a potential risk to both animals, humans, and public heaths.…”

“…Also, Wang et al from China reported a high incidence of sopB (100%), and spvC (93.8%) among Salmonella serovars isolated from 120 retail meat samples ( 41 ). In studies in Iran and Nigeria the prevalence rates of spvC gene were 50.8%, 59.1%, and 45.8%, respectively ( 26 , 28 ). According to a study by Takaichi et al conducted in Indonesia, the prevalence rates of slyA, phoP/Q, and sopB were reported as 60%, 86%, and 88%, respectively ( 42 ).…”

Prevalence and antimicrobial resistance of Salmonella enterica serovars Enteritidis and Typhimurium isolated from retail chicken meat in Wasit markets, Iraq

“…Therefore, this investigation tried to provide useful data to understand the connection between the utilization of antimicrobial agents in poultry production and the upsurge of the emergence of resistance in foodborne pathogens, such as Salmonella. The previous studies in Iraq confirmed this relationship by investigating the MDR phenomenon in many foodborne pathogens [21,[48][49][50][51]. Other studies in Iraq also pointed to wrong practices regarding the abuse and misuse of antibiotics, which drove the exacerbation of this phenomenon [52][53][54].…”

“…Salmonella has long been linked to poultry and related products [ 21 ]. In recent years, there has been widespread reporting of the growing prevalence of Salmonella and antimicrobial resistance (AMR) in food [ 22 ].…”

“…Disparities in antimicrobial classes, antibiotics utilization, bacterial serovars, and country of origin of the resulting isolates have all been linked to variances in resistance and susceptibility proportions [ 21 ].…”