Prevalence and antimicrobial resistance patterns of Listeria species isolated from poultry products marketed in Iran

In the present study, a total of 402 poultry product samples composed of raw, ready-to-cook (RTC) and ready-to-eat (RTE) products were examined for the presence of Listeria spp. The total contamination rate with Listeria spp. in poultry products was 33.3% with a higher rate of contamination in warm seasons than in cold seasons. The most species recovered was Listeria innocua (46.3%); the remaining isolates were Listeria monocytogenes (38.8%), Listeria ivanovii (9.7%) and Listeria seeligeri (5.22%). L. monocytogenes was detected in 14.1%, 12.2% and 11.4% of raw, RTC and RTE poultry products, respectively. Serotype 4b (44.9%) was the predominant serotype of L. monocytogenes isolates followed by 1/2a (40.8%), 1/2b (10.2%) and 1/2c (4.08%). Considering seasonal variability, 1/2a was the most prevalent serotype in warm seasons, while 4b was predominant in cold seasons. The Listeria spp. particularly L. monocytogenes isolates were highly resistant to ampicillin, penicillin, fluroquinolones and tetracycline. The results indicate that high prevalence of Listeria spp. especially L. monocytogenes in poultry products, and resistance of the isolates to the antimicrobials commonly used to treat human listeriosis could be a potential health hazard for consumers. In addition, prevalence of L. monocytogenes serotype 4b that involved in the majority of foodborne outbreaks of human listeriosis is a public health concern.     

Microbiological quality of ready-to-eat minimally processed vegetables consumed in Brazil

Minimally processed leafy vegetables are ready-to-eat (RTE) products very attractive to consumers looking for healthy and convenient meals. However, the microbiological safety of these foods is of special concern due to the absence of lethal treatments during processing. In the present study, indicator microorganisms, Listeria spp. and Salmonella spp. were determined for 162 samples of minimally processed leafy vegetables commercialized in Brazil. Psychrotrophic aerobic bacterial populations >5 log CFU/g were found in 96.7% of the samples, while total and thermotolerant coliforms were detected respectively in 132 (81.5%) and 107 (66%) of vegetables analyzed. Escherichia coli was present in 86 (53.1%) samples analyzed and Listeria spp. and Salmonella spp. were detected respectively in 6 (3.7%) and 2 (1.2%) samples. These results indicate the need of implementing quality programs in the production chain of RTE vegetables to improve shelf life and microbiological safety.     

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

Listeria monocytogenes is the causal agent of listeriosis, a disease that can be serious and is often fatal in susceptible individuals. The objective of the study was to determine the prevalence of Listeria spp. in raw chicken and ready-to-eat (RTE) chicken products in Amman, Jordan and the antimicrobial resistance of L. monocytogenes isolates. A total of 280 raw chicken and RTE chicken products (chicken-shawirma, chicken-burger, chicken-sausage and mortadella) were collected from Amman abattoir and local retail markets in Amman city. Listeria spp. were isolated by the conventional International Organization for Standardization (ISO) method and L. monocytogenes identified by biochemical and Polymerase Chain Reaction (PCR). Results of conventional method showed that out of total 280 samples, 141 (50%) were found to be contaminated with Listeria spp. [L. monocytogenes (18.2%), Listeria ivanovi (26.1%), Listeria grayi (3.5%), Listeria seeligeri (1.8), Listeria welshimeri (0.7%)]. The PCR confirmed all L. monocytogenes isolates (51 isolates: 15 from raw dressed broiler chicken, 23 from chicken-burger, 9 from chicken-sausage, and 4 from chicken-shawirma). Five of the tested L. monocytogenes isolates were resistance to two antibiotics (tilimicosin and tetracycline) among the ten tested antibiotics as determined by microbroth dilution method. The results presented in this study indicate the potential risk of contamination of RTE chicken products with L. monocytogenes.     

Prevalence of Listeria spp. in ready to eat foods (RTE) from Algiers (Algeria)

The aim of this study was to establish the occurrence of Listeria spp., especially Listeria monocytogenes in ready to eat RTE food marketed in Algiers (Algeria).A total of 227 samples were collected from different producers and retailers.All samples were analyzed using a conventional cultivation method AFNOR V08-055.Out of 227 samples tested, 21 (9.3%) tested positive for Listeria spp. among them, 6 (2.6%) tested positive for L. monocytogenes. L. innocua was the most common Listeria species found being detected in 11 samples (4.8%), although both Listeria ivanovii and Listeria welshimeri were detected in 3 (1.3%) and 1 (0.4%) food samples respectively.The study of the antimicrobial sensitivity of Listeria monocytogenes strains showed no resistance.The study has enabled us to detect these contaminants in a wide range of RTE foods, to suggest that contamination likely occurs after heat treatment, and to assess the danger represented by this category of food for populations at risk.     

Prevalence and characterization of Listeria monocytogenes isolated from retail-level ready-to-eat foods in South China

Listeria monocytogenes is an important food-borne pathogen causing meningitis, meningoencephalitis and abortion. To assess the potential risk to consumer health, the presence of L. monocytogenes was investigated using qualitative and quantitative methods. Ten (6.33%) of 158 retail RTE food samples were positive for L. monocytogenes and the contamination levels were less than 10 MPN/g,while none of 65 dairy products was positive for L. monocytogenes. The 37 strains were grouped into five clusters and two singletons, five clusters and two singletons, and three clusters and one singleton by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and RAPD fingerprint respectively, at similarity coefficient of 80%. The susceptibility test showed that 83.8% were susceptible to 15 antimicrobials; two were penicillin-resistant, and one was multidrug-resistant to kanamycin, tetracycline, sulfamethoxazole, rifampin, gentamycin, penicillin, and ampicillin. Virulent L. monocytogenes that possess partial antimicrobial resistance, and serotypes frequently associated with listeriosis were recovered from RTE foods. Consumers may, therefore, be exposed to potential risks of L. monocytogenes infection in South China. This study contributed to the prevalence and contamination levels of L. monocytogenes in RTE foods in South China for the first time, providing baseline information for Chinese regulatory authorities to formulate a regulatory framework for controlling L. monocytogenes to improve the microbiological safety of RTE foods.     

Successful management of Listeria spp. in an avocado processing facility

Listeria monocytogenes can grow and multiply in various food matrices and cause severe human illness. Apart from the influence on consumer health, L. monocytogenes contamination of ready-to-eat (RTE) food products causes major economic losses due to product recalls. Control of foodborne pathogens in RTE food products is a challenge, specifically in foods that cannot undergo a heat-treatment during processing. The aim of this study was to develop control strategies for the management of L. monocytogenes in an avocado processing facility, additional to a quality control system. An in-house monitoring system (IMS) was established to test specifically for Listeria spp. in the final products and processing environment, including floors, equipment, work areas and personnel. Guacamole and environmental samples were collected and tested on-site for Listeria with the ISO 11290-1 method. Based on the prevalence of Listeria, the facility introduced new strategies in processing to counter cross contamination. Results from the 2014 guacamole production season showed almost complete eradication of Listeria spp. in final products (0.17%, n = 1170) and the processing facility (0.79%, n = 1520). This is a major achievement since the highest incidence of Listeria spp. over a period of five years was measured at 11.39% (n = 948) in the final product during the 2013 season and 13.44% (n = 1927) in the processing facility in 2011. These results indicate that successful management of Listeria spp. in an avocado processing facility can be accomplished with in-house monitoring of the listerial population and subsequent adjustments to the processing system.     

Occurrence and characterization of nontyphoidal Salmonella in retail table eggs in Kandy district of Sri Lanka

Salmonellosis in humans is typically a foodborne bacterial zoonotic disease. In this regard, eggs and egg products contaminated with nontyphoidal Salmonella represent a serious threat to consumers. Eggs are one of the most common sources of animal protein for Sri Lankans but minimum attention is paid to their quality assurance. Except for a few packaged eggs sold under brand names for higher prices, in general, grading, cleaning or cooling is not practised before sale posing a microbiological health hazard to the general public. Hence, the objective of this study was to identify the presence of Salmonella in raw table eggs available at retail outlets in one selected district of Sri Lanka. Eggs were purchased from 100 retail outlets situated in highly populated areas of the district. Samples were tested for the presence of Salmonella in eggshell washings and egg contents, separately. Isolation and identification of Salmonella was performed according to standard methods. The isolates were serotyped and their antimicrobial sensitivity was determined. Salmonella was isolated from the eggs purchased from 15 retail outlets, of which 12 yielded Salmonella from shell washings and three from egg contents. The serovars identified were S. Mbandaka, S. Braenderup, S. Corvallis, and S. Emek. Except one isolate showing resistance to nalidixic acid and another to a third generation cephalosporin, other isolates were sensitive for the tested antimicrobials. According to the results of this study, retail raw table eggs can be considered as an important source of nontyphoidal Salmonella to egg consumers in Sri Lanka.     

Campylobacter contamination in retail poultry meats and by-products in Japan: A literature survey

Campylobacter species are common bacterial pathogens that cause gastroenteritis in humans worldwide. In Japan, campylobacteriosis is the leading food-borne bacterial illness, and the consumption of poultry meats and/or by-products is suspected to be the major cause of this illness. In this review, we summarized the papers describing Campylobacter contamination of retail poultry meats and by-products in Japan, most of which were written in Japanese, for estimating the nationwide situation of Japan. On the average, the prevalence of Campylobacter contamination in retail poultry meats and by-products was approximately 60%; this contamination level is comparable to those observed in North America and Europe. Campylobacter jejuni was the dominant species isolated from retail poultry, and Penner serotype 2 and 4-complex were the predominant serotypes of C. jejuni. A large section of poultry was contaminated with Campylobacter spp. at levels that were adequate to induce gastroenteritis if the meat consumed was raw or undercooked. Moreover, quinolone resistance was frequently found in poultry isolates. This review provides detailed and referable data on Campylobacter contamination of retail poultry meats and by-products in Japan, especially for researchers of other countries.     

Prevalence and antimicrobial resistance of Listeria species isolated from milk and dairy products in Iran

The objective of this study was to determine the prevalence of Listeria spp. in milk and dairy products in Isfahan province, Iran. From March 2007 to September 2009, a total of 594 samples of various milk and dairy products were obtained from randomly selected retail stores. Using conventional bacteriologic method, 55 samples (9.3%) were positive for Listeria spp. The highest prevalence of Listeria was found in raw sheep milk samples (22.6%), followed by cheese samples (18.9%). The most species recovered was Listeria innocua (58.2%); the remaining isolates were Listeria monocytogenes (32.7%) and Listeria seeligari (9.1%). Overall, 54 Listeria isolates (98.2%) were resistant to one or more antimicrobial agents. Resistance to nalidixic acid was the most common finding (96.4%). All Listeria isolates were susceptible to vancomycin. The results of this study indicate the potential risk of infection with Listeria in people consuming raw and unpasteurized milk and dairy products.     

Hygienic conditions and microbiological status of chilled Ready-To-Eat products served in Southern Spanish hospitals

Chilled Ready-To-Eat (RTE) foods are of concern in hospital foodservices because they can support microbial growth when subjecting to time/temperature abuses during processing and distribution together with poor handling practices. This study was conducted in five different hospitals (A–E) of Southern Spain during 2008–2009 to perform an evaluation of their sanitary conditions and microbiological quality of two RTE meals: lettuce salads and cooked ham. A checklist based on hygiene principles embedded in Food European legislation was developed and applied in each hospital. In parallel, microbiological analysis of food contact surfaces, air quality and time/temperature measurements along the distribution chain were carried out. RTE samples (n = 150) were examined for mesophilic aerobic bacteria (MAB), total coliforms, coagulase-positive Staphylococci (CPS), Escherichia coli, Listeria spp. and Salmonella spp. Differences were found between hospitals regarding handling practices and cleanliness of working surfaces. Cooked ham samples presented lower counts of MAB and total coliforms (<10³ and <10 cfu/g respectively) than lettuce salads (10⁴ to 10⁵ and 10 to 10⁴ cfu/g respectively), although concentration of CPS was higher in cooked ham samples reaching maximum levels close to 10³ cfu/g. Neither Listeria spp. nor Salmonella spp. were detected in any food sample. Prevalence of E. coli was low (3%). Surface counts and air quality presented high variability among the different hospitals evaluated. It was concluded that good manufacturing practices and HACCP principles should be followed together with special training of food handlers. This study can help risk managers to better define the control measures to be adopted in healthcare settings in order to prevent foodborne infections.     

Prevalence,antimicrobial resistance and genetic diversity of Salmonella isolated from retail ready-to-eat foods in China

Salmonella is a leading cause of foodborne disease worldwide and ready-to-eat (RTE) foods are regarded as a major source of infection and outbreak. In recent years, the consumption of Chinese RTE foods has raised markedly with the pace of life increasing. However, the prevalence of Salmonella in these foods in China and its potential risk to public health has not been well determined and evaluated. This study was undertaken to investigate the prevalence of Salmonella in Chinese retail RTE food products and to determine serotype distribution, antimicrobial resistance, virulence, and genetic diversity of recovered Salmonella isolates. Out of the 539 RTE food products collected and tested from July 2011 to May 2014, 19 (3.5%) were positive for Salmonella. The contamination levels of Salmonella were mostly in the range of 0.3–10 most probable number (MPN)/g, with one sample exceeding 110 MPN/g. Among the 50 isolates identified, 37 isolates (74.0%) were resistant to at least one antimicrobial, while 21 isolates (42.0%) were resistant to more than three antimicrobials. High rates of resistance were observed for tetracycline (56.0%), ampicillin (38.0%), and streptomycin (34.0%). PCR analysis of 15 virulence genes showed that the avrA, ssaQ, mgtC, siiD, sopB, and bcfC genes were detected in all 50 isolates, whereas the genes located on plasmid and prophage varied significantly among the isolates. Ten distinct serovars were identified and S. Derby, S. Meleagridis, S. Enteritidis, and S. Senftenberg were the most prevalent serovars. A total of 11 sequence types by multilocus sequence typing and 20 profiles by pulsed-field gel electrophoresis were generated for the 20 selected isolates and the combination of these two methods presented a better knowledge of genetic diversity of Salmonella isolates. The study provided a systematical surveillance on prevalence of Salmonella in Chinese RTE foods and indicates its potential risk to public health.     

Food safety in the domestic environment

The main purpose of this work was to evaluate the significance of food safety in domestic environments. In this study, several points in 15 houses (handles of doors, refrigerators and dishwashers, cooking stove knobs, surfaces of preparation of foods, taps and kitchen towels, as well as from domestic animals' feet that usually have access to the kitchen area, and WC knobs and taps) were sampled and tested for detection and quantification of Enterobacteriaceae, Staphylococcus coagulase-positive, Escherichia coli, Listeria spp. and Campylobacter spp. A questionnaire was also prepared and administered to the person responsible for domestic tasks in order to evaluate their experience of hygienic practices. The results showed a total of 125 Enterobacteriaceae spp. isolates, 86 Staphylococcus coagulase-positive isolates, 5 Listeria spp., 13 E. coli isolates and no Campylobacter spp. was found. Most of the isolates were found distributed by the entire house, with handles, knobs and domestic animals' feet being the points more contaminated. Also, there was no relation between the answers to the questionnaires administered and the microbiological results obtained. These results revealed the need to develop some education campaigns designed to educate consumers in good hygiene practices at home.     

Listeria monocytogenes in ready-to-eat vacuum and modified atmosphere packaged meat and fish products of Estonian origin at retail level

The prevalence, counts and genetic diversity of Listeria monocytogenes in ready-to-eat (RTE) vacuum and modified atmosphere packaged meat and fish products was studied in Estonia. Within two consecutive years 370 RTE food samples were collected at retail level from which 11% were found to be positive for L. monocytogenes. Contamination was higher among RTE fish products (17%) than in RTE meat products (6%). Generally, the counts of L. monocytogenes in positive products remained under ten colony forming units (CFU) per gram of product. Only 1.6% of the RTE meat and fish products contained L. monocytogenes in range of 10–100 CFU/g and 0.3% more than 100 CFU/g at the end of shelf-life. The food category containing highest L. monocytogenes prevalence was RTE lightly salted fish products with the prevalence of 32%. Only one (0.3%) RTE food sample exceeded the 100 CFU/g food safety criterion set out in the EU Regulation 2073/2005. Pulsed-field gel electrophoresis (PFGE) characterization of the isolates showed an overall similarity higher than 70%, and nine clusters based on 100% similarity were revealed. PFGE genotyping revealed that the few predominant pulsotypes were associated with particular food plants.     

Changing regulation: Canada's new thinking on Listeria

In 2008, Canada experienced one of its most serious outbreaks of foodborne listeriosis. During this outbreak, which was eventually traced back to contaminated deli-meat, there were 57 cases of illness and 23 deaths. As a result of the outbreak, the Canadian Food Inspection Agency (CFIA) has developed new Directives for the registered meat and poultry sector. Under the new requirements, production facilities must implement food contact surface testing for Listeria spp. and/or Listeria monocytogenes. The enhanced requirements focus on early detection and control of L. monocytogenes by introducing new testing and reporting requirements for industry, e.g., positive test results from all food contact surface testing must now be immediately reported to the CFIA and companies must perform trend analysis on their test results.In addition, work has begun on updating the current Health Canada policy on L. monocytogenes. The Canadian approach to Listeria control stresses the importance of environmental sampling. In addition to government agencies and food industries working diligently at minimizing the exposure to L. monocytogenes, consumers also have an important role to play in the farm-to-fork continuum. That role calls for Canadians to learn and adopt safe food handling, avoidance of certain high-risk foods, and preparation practices. To this effect, Health Canada has and will continue to undertake the development of science-based consumer education material which will help create an understanding of food safety issues within the context of the public’s right to know about the potential dangers in food, and industry’s responsibility for producing safe food. A combination of all these approaches are currently being adopted and/or developed to improve the control of L. monocytogenes in RTE foods sold in Canada.     

Campylobacter species and their antimicrobial resistance in Latvian broiler chicken production

In the present study Campylobacter species and their antimicrobial resistance in Latvian broiler chicken production was determined. Furthermore, this is the first report on the antimicrobial resistance patterns for Campylobacter isolates from broiler chickens at slaughterhouse and retail level in Latvia. Two biggest Latvian broiler chicken meat producing company products were included in the study. Altogether, 74 randomly selected broiler chicken Campylobacter spp. isolates were analysed for species identification. Campylobacter isolates were obtained during a 12-month period within the Latvian Campylobacter prevalence study in 2010. Colony multiplex PCR was used for all isolates to identify Campylobacter species. Minimal inhibitory concentration (MIC) was determined for 58 Campylobacter spp. isolates. Resistance to one or more antimicrobials was detected in all 58 isolates (100%). A high proportion of the isolates were resistant to ciprofloxacin (100%) and nalidixic acid (87.9%). Multidrug resistance, which was determined as resistance to three or more unrelated antimicrobials, was detected in 39 isolates (67.2%). Moreover, all multiresistant isolates were resistant to ciprofloxacin and nalidixic acid. Analyses of Campylobacter isolates from two Latvian broiler chicken meat producing companies resulted with significant differences in Campylobacter species; from the company A mainly Campylobacter coli were found, while in the company B Campylobacter jejuni.     

Quality of raw milk intended for direct consumption in Estonia

The main aim of the present study was to estimate the occurrence of zoonotic bacteria in raw milk intended for sale directly to consumers in Estonia. In-line milk filters, bulk milk samples and milk samples from selling points were collected from a total of 14 dairy farms and respective retail selling points. The somatic cell counts, total bacterial counts and the presence of Salmonella spp and Listeria monocytogenes were studied from bulk milk samples. Campylobacter spp., Salmonella spp., L. monoscytogenes and Shiga-toxin producing Escherichia coli (STEC) were studied in farms in-line milk filters. The total bacterial counts exceeded 100,000 cfu/ml in three (21.4%) bulk milk samples and in 10 samples (71.4%) collected at the retail level. STEC genes were detected in 64.3% of the in-line milk filter samples. More than one STEC serogroup-specific gene was detected in four dairy farms. L. monocytogenes was found in 36% of the in-line milk filters. Neither Salmonella spp. nor Campylobacter spp. were found in any samples.     

Listeria detection in microscale solid state inoculation with minimal selective agents

The food industry needs a simple, reliable, and cost-effective primary screening protocol for routine inspection of bacterial contamination. Microscale inoculation technique is proposed as an alternative method for Listeria detection. This proposed novel technique shows a good correlation with standard spread plate technique for the enumeration of pure Listeria cultures (R² = 0.96, P < 0.0001). The commonly used selective agents in Listeria media (PALCAM, MOX, and OCLA) were assessed for their inhibitory effect on Listeria monocytogenes, Listeria innocua, and Listeria ivanovii using the microscale inoculation technique. The concentration of selective agents was lowered to inhibit competitive bacteria with minimum impact on the growth of Listeria. At the standard concentration, all three media showed less inhibition on L. monocytogenes and L. innocua than on L. ivanovii. OCLA had less inhibitory effect on the three species than did MOX and PALCAM. The comparison between ISO 11290-1 and microscale with 25% of selective agent concentration on detection of Listeria in 36 naturally contaminated food samples revealed that the microscale technique agreed well with the ISO method (Cohen KAPPA = 0.83). Reduction of selective agent concentration to 25% of the conventional formulas resulted in substantial improvement in detectability of Listeria spp. without significantly reducing specificity. The detection sensitivity of the Listeria colonies in food samples was significantly improved by microscale inoculation with 25% of the inhibitors on the three selective media at 24 and 48 h incubation (ANOVA, P = 0.039). At 48 h incubation the improvement was from 95%, 90%, and 85% (ISO method with regular strength inhibitors) to 100%, 100%, and 90% (microscale) on OCLA, MOX, and PALCAM respectively. There was no discrepancy between the microscale and the ISO method in detection of L. monocytogenes in the food samples. The optimization of Listeria detection improves sensitivity of detection as well as reducing media volume which may reduce costs and waste generated.     

Prevalence of food-borne pathogens in ready-to-eat meat products in seven different Chinese regions

Microbiological surveillance of ready-to-eat (RTE) meat products provides empirical data to inform scientific guidance for improving food safety. In this study we conducted the first nation-wide survey of food-borne pathogens in RTE meat products in China in 2013. We analyzed the prevalence of food-borne pathogen in different product categories, market distribution, packaged forms, seasonal variation and regions. In total, 4047 samples were collected from all seven regions in China representing distinct geographical areas: Northern, Northeastern, Eastern, Central, Southern, Southwestern, and Northwestern Regions. Samples were collected from catering, retail, and wholesale sources in different seasons throughout the course of the year. The presence of Listeria monocytogenes, Salmonella spp., Staphylococcus aureus and diarrheagenic Escherichia coli in all the samples was examined by China's national food safety standard method. All the surveillance data were analyzed according to meat product category, market distribution, packaged form, seasonal variation and regions, respectively. Microbial prevalence of L. monocytogenes, Salmonella spp., S. aureus and diarrheagenic E. coli were detected in 1.43% (57/3974), 0.64% (26/4035), 0.79% (32/4047) and 1.06% (40/3774), respectively. The prevalence of heat-treated category RTE meat products was high, probably due to cross contamination. Prevalence data for Salmonella spp. and S. aureus were higher in the third quarter of the year. We found packaging method played a consistent role in the prevalence of all four food-borne pathogens in packaged ready-to-eat meat products. Bulk ready-to-eat meat products were significantly more likely to contain contamination than portion packaged products. In all, this study implied a potential public health problem. It is necessary to improve control measures of RTE meat products.     

Contamination of post-harvest poultry products with multidrug resistant Staphylococcus aureus in Maryland-Washington DC metro area

We investigated the prevalence of Staphylococcus aureus and multidrug including methicillin-resistant S. aureus (MRSA) in poultry retail meat samples from the Maryland-Washington DC metro area. A total of 24 S. aureus isolates were recovered from 96 whole poultry carcass samples and the prevalence of S. aureus were 25.0%, 14.29%, and 33.3% in retail poultry meats collected from farmers markets, organic and conventional retail supermarkets, respectively. Both single and multi-drug resistance isolates were detected in 58.3% (7/12) isolates from conventional retail meat products but none from farmers markets or organic retail meat isolates. Conventional retail meat isolates were found to be resistant to both erythromycin (50.0%) and tetracycline (58.3%). We also detected an MRSA isolate harboring mecA gene in conventional retail meat which showed co-resistance towards erythromycin, tetracycline, and vancomycin.     

Lethality of moist heat and silver dihydrogen citrate sanitizer combinations on Listeria spp. adhered to components of a deli meat slicer

Deli meat slicers have been implicated in cross-contamination of ready-to-eat (RTE) foods with Listeria monocytogenes that has resulted in several listeriosis outbreaks. We investigated the lethality of moist heat and silver dihydrogen citrate (SDC) sanitizer on Listeria species that were inoculated on stainless steel (SS) and cast aluminum (AL) coupons cut from actual components of a deli meat slicer. The coupons inoculated with Listeria species were subjected to treatments inside and outside of meat slicer using a commercial bread proofer that was operated for 7 h at 66 °C. Post treatment recoveries of the inoculated Listeria from the treated coupons were enumerated using MOX growth medium. All treatments produced significant (P = 0.05) log reductions compared with positive and untreated negative controls. Moist heat reduced the inoculated bacteria to non-detectable levels when the coupons were placed inside the motor compartment of the slicer and the sanitizer plus moist heat gave same results for the coupons placed inside and outside of the slicer. Chemical sanitizer treatment alone showed average log reductions of around 5 CFU/cm² on AL and SS coupons respectively and the moist heat alone treatment on both AL and SS coupons showed a log reduction of 4.49 and 4.87 when placed externally and above 6 logs when placed inside the motor compartment. Sanitizer plus moist heat treatments showed highest log reductions of Listeria species to non-detectable levels on deli meat slicer components when placed inside or outside the motor compartment of the slicer. Thus the sanitizer and moist heat combination treatments can effectively reduce the Listeria cells attached onto food contact surfaces of a deli meat slicer.