Incidence and Contamination Level of Listeria monocytogenes and Other Listeria spp. in Ready-to-Eat Meat Products in Jordan

Abstract

The objective of the present study was to investigate the incidence and contamination levels of different Listeria monocytogenes serovars in ready-to-eat meat products (RTE-MP) collected from different outlets and processing plants in Jordan in order (i) to provide information to Jordanian health authorities on the incidence of L. monocytogenes in RTE-MP sold and consumed in Jordan and (ii) to ascertain the risks of these products for consumers. Two hundred forty RTE-MP samples, 120 beef and 120 poultry, were analyzed. European International Organization for Standardization (EN ISO) 11290-1 and -2 standard protocols were used for detection and enumeration of L. monocytogenes. The identity of suspected L. monocytogenes was confirmed using PCR. Three Listeria spp., L. monocytogenes, L. innocua, and L. welshimeri, were isolated. L. innocua and L. welshimeri were the most and least frequently isolated with 56 and 36 samples, respectively. L. monocytogenes was isolated from 41 samples (17.1%): 23 from beef and 18 from poultry samples. The contamination levels of L. monocytogenes were <or=100 CFU/g in 97.5% (40 samples) of the positive samples. Only one beef sample with a count of >100 CFU/g was found. The L. monocytogenes strains isolated fell into two serotypes (1 and 4) and four different serovars (1/2a, 1/2b, 1/2c, and 4b).

Prevalence of Listeria spp. and antibiotic susceptibility of Listeria monocytogenes isolated from raw chicken and ready-to-eat chicken products in Jordan

“…To our knowledge only one study concerning isolation of Listeria spp. from RTE deli meat products has been reported in Jordan (Awaisheh, 2010) but no study concerning isolation of Listeria spp. from raw chicken was found.…”

Isolation of Listeria monocytogenes in lamb meat and determination of the antibiotic resistance

“…The last isolate was resistant to streptomycin, meropenem, trimethoprim/ sulfamethoxazole and was intermediate to gentamicin. Resistance to streptomycin, meropenem, trimethoprim/ sulfamethoxazole was most common with 4 isolates showing resistance, then gentamicin (3 resistant isolates and 1 intermediate), penicillin G and rifampicin [3], and finally, erythromycin and tetracycline [2]. All isolates were sensitive to ampicillin (Table 4).…”

Molecular characterization and antibiogram of Listeria monocytogenes isolated from chicken and mutton of retail markets

“…Multiplex PCR has been widely used for the molecular characterization of Listeria isolates by several researchers [13,21,22]. It offers the advantage of simultaneous identification as well as molecular characterization of the L. monocytogenes isolates recovered from the meats and helps in the detection of virulence determinants of Listeria species [13,23].…”