Occurrence and antibiotic susceptibility ofListeria monocytogenesisolated from raw and processed meat products in Amman, Jordan

A total of 270 samples of raw and processed meat products were collected at retail in Amman, Jordan and tested for the presence of Listeria spp. by conventional bacteriological methods. L. monocytogenes isolates were confirmed by PCR using L. monocytogenes virulence gene primers actA, hlyA, iap, inlA, inlB, inlC and inlJ. The overall occurrence of L. monocytogenes was 24.4% using the culture method and 21.9% using the PCR technique. L. ivanovii was the main Listeria spp., with an overall occurrence of 27%, while L. welshimeri and L. seeligeri showed the lowest occurrence in both types of product. All confirmed the L. monocytogenes isolates were sensitive to ampicillin, gentamicin and vancomycin while 56.6, 10, 6.7 and 5% of isolates were resistant to neomycin, tetracycline, kanamycin and erythromycin, respectively. This first report on the presence of Listeria in raw and processed meats in Jordan indicates that these products may pose a risk of listeriosis.