Contamination of Citrobacter spp. in food and sales environment samples and the antibiotics resistance profile of the isolates

Abstract

Objective To investigate the contamination of Citrobacter spp. in food and sales environment samples in Shijiazhuang City discovery the antibiotics resistance profile of the Citrobacter spp. isolates, and provide scientific basis for the prevention of foodborne diseases caused by the bacterium and clinical treatment. Methods Four kinds of food samples including animal meat, poultry meat, aquatic products and cooked food and sales environment samples were collected from four urban counties and four suburban counties in Shijiazhuang. Citrobacter spp. were isolated and then the antibiotics resistance analysis of the isolates were performed. All the strains were identified by matrix-assisted laser desorption ionization time of flight mass spectrometry(MALDI-TOF MS) system and VITEK 2 Compact system. Antibiotics susceptibility was performed by broth microdilution method. Results Among the 320 samples, 62 samples were Citrobacter spp. positive(19.4%,62/320), and 72 Citrobacter spp. strains were isolated. The contamination rate of Citrobacter spp. were 28.2%(33/117) in animal meat, 21.3%(10/47) in poultry meat, 18.2%(8/44) in aquatic products, 15.7%(8/51) in cooked food and 4.9%(3/61) in sales environment samples. There were significant differences in the contamination rate of Citrobacter spp. in food samples and sales environment samples (χ2=10.08, P0.05). The antibiotic resistance of the strains were serious. Most of the Citrobacter spp. strains were resistant to cefazolin(93.1%, 67/72), and cefoxitin(81.9%, 59/72). All of the Citrobacter spp. strains were not sensitive to meropenem. There were seven Citrobacter spp. produced extended-spectrum β- lactamase (ESBLs),, and most of the Citrobacter spp. strains were found to be multiple drug resistance(MDR)(91.7%, 66/72). Conclusion The contamination of Citrobacter spp. in food samples was quite severe and most of the Citrobacter spp. isolates were antibiotic resistant and MDR. Citrobacter spp. had a potential food poisoning risk and it should be paid great attention.

Keywords

• citrobacter spp.
• food
• sales environment
• contamination
• antibiotics resistance
• foodborne disease