Distribution, contamination routes, and seasonal influence of persistent Listeria monocytogenes in a commercial fresh Hypsizigus marmoreus production facility

Abstract Test portions from 3 environmental surface types, representative of typical surfaces found in a food production facility, were analyzed by the Visual Immunoprecipitate assay (VIP®) and the U.S. Department of Agriculture/Food Safety and Inspection Service (USDA/FSIS) culture method for Listeria monocytogenes and related Listeria species. In all cases, naturally contaminated environmental test samples were collected from an actual food production facility by sponge or swab. Test samples from concrete surfaces were collected by both swab and sponge; sponge test samples were collected from rubber surfaces, and swabs were used to sample steel surfaces. Test portions from each surface type were simultaneously analyzed by both methods. A total of 27 laboratories, representing government agencies as well as private industry in both the United States and Canada, participated in the study. During this study, a total of 615 test portions and controls was analyzed and confirmed, of which 227 were positive and 378 were negative by both methods. Nine test portions were positive by culture, but negative by the VIP. Five test portions were negative by culture, but positive by the VIP. Four test portions were negative by VIP and by culture, but confirmed positive when VIP enrichment broths were subcultured to selective agars. The data reported here indicate that the VIP method and the USDA/FSIS culture method are statistically equivalent for detection of L. monocytogenes and related Listeria species from environmental surfaces taken by sponges or swabs.

Download Full-text

Incidence of Listeria monocytogenes and Listeria spp. in a Small-Scale Mushroom Production Facility

Journal of Food Protection ◽

10.4315/0362-028x.jfp-12-292 ◽

2013 ◽

Vol 76 (4) ◽

pp. 608-615 ◽

Cited By ~ 26

Author(s):

PREMA VISWANATH ◽

LATHA MURUGESAN ◽

STEPHEN J. KNABEL ◽

BINDHU VERGHESE ◽

NAVEEN CHIKTHIMMAH ◽

...

Keyword(s):

United States ◽

Listeria Monocytogenes ◽

Foodborne Pathogen ◽

Disease Outbreaks ◽

The United States ◽

Raw Material ◽

Small Scale ◽

State University ◽

Production Facility ◽

Mushroom Production

Listeria monocytogenes is a foodborne pathogen of significant concern to the agricultural and food processing industry because of its ability to grow and persist in cool and moist environments and its association with listeriosis, a disease with a very high mortality rate. Although there have been no listeriosis outbreaks attributed to fresh mushrooms in the United States, retail surveys and recalls are evidence that L. monocytogenes contamination of mushrooms (Agaricus bisporus) can occur. The objective of this study was to determine the prevalence of Listeria spp., including L. monocytogenes, in a small-scale mushroom production facility on the campus of the Pennsylvania State University in the United States. Of 184 samples taken from five production zones within the facility, 29 (15.8%) samples were positive for Listeria spp. Among the Listeria spp. isolates, L. innocua was most prevalent (10.3%) followed by L. welshimeri (3.3%), L. monocytogenes (1.6%), and L. grayi (0.5%). L. monocytogenes was recovered only from the phase I raw material composting area. Isolates of L. monocytogenes were confirmed and serotyped by multiplex PCR. The epidemiological relatedness of the three L. monocytogenes isolates to those serotypes or lineages frequently encountered in listeriosis infections was determined by multi-virulence-locus sequence typing using six virulence genes, namely, prfA, inlB, inlC, dal, clpP, and lisR. The phylogenetic positions of the three isolates in the dendrogram prepared with data from other isolates of L. monocytogenes showed that all isolates were grouped with serotype 4a, lineage IIIA. To date, this serotype has rarely been reported in foodborne disease outbreaks.

Download Full-text

Possible Contamination Routes of Listeria monocytogenes in Leaf Lettuce during Cultivation

Food Science and Technology Research ◽

10.3136/fstr.24.911 ◽

2018 ◽

Vol 24 (5) ◽

pp. 911-920 ◽

Cited By ~ 1

Author(s):

Ken-ichi Honjoh ◽

Yin Lin ◽

Kiyomi Jo ◽

Yuri Iwaizako ◽

Masayuki Maeda ◽

...

Keyword(s):

Listeria Monocytogenes ◽

Contamination Routes ◽

Leaf Lettuce

Download Full-text

Method Extension Study to Validate Applicability of AOAC Official Method 996.14 Assurance® Polyclonal Enzyme Immunoassay for Detection of Listeria monocytogenes and Related Listeria spp. from Environmental Surfaces: Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/85.2.460 ◽

2002 ◽

Vol 85 (2) ◽

pp. 460-469 ◽

Cited By ~ 2

Author(s):

Philip T Feldsine ◽

Andrew H Lienau ◽

Stephanie C Leung ◽

Linda A Mui ◽

J Aharchi ◽

...

Keyword(s):

Listeria Monocytogenes ◽

Enzyme Immunoassay ◽

Food Production ◽

Culture Method ◽

The United States ◽

Official Method ◽

Production Facility ◽

Private Industry ◽

Listeria Species ◽

Environmental Surfaces

Abstract Test portions from 3 environmental surface types, representative of typical surfaces found in a food production facility, were analyzed by the Assurance®Listeria Polyclonal Enzyme Immunoassay (EIA) and the U.S. Department of Agriculture/Food Safety and Inspection Service (USDA/FSIS) culture method for Listeria monocytogenes and related Listeria species. In all cases, naturally contaminated environmental test samples were collected from an actual food production facility by sponge or swab. Test samples from concrete surfaces were collected by both swab and sponge; sponge test samples were collected from rubber surfaces, and swabs were used to sample steel surfaces. Test portions from each surface type were simultaneously analyzed by both methods. A total of 23 collaborators, representing government agencies, as well as private industry in both the United States and Canada, participated in the study. During this study, a total of 550 test portions and controls was analyzed and confirmed, of which 207 were positive and 336 were negative by both methods. Six test portions were positive by culture, but negative by the EIA. Three test portions were negative by culture, but positive by the EIA. Two test portions were negative by EIA and by culture, but confirmed positive when EIA enrichment broths were subcultured to selective agars. The data reported here indicate that the Assurance®Listeria EIA method and the USDA/FSIS culture method are statistically equivalent for detection of L. monocytogenes and related Listeria species from environmental surfaces taken by sponges or swabs.

Download Full-text

Putative Cross-Contamination Routes of Listeria monocytogenes in a Meat Processing Facility in Romania

Journal of Food Protection ◽

10.4315/0362-028x.jfp-14-539 ◽

2015 ◽

Vol 78 (9) ◽

pp. 1664-1674 ◽

Cited By ~ 17

Author(s):

ANDREI SORIN BOLOCAN ◽

ELENA ALEXANDRA ONICIUC ◽

AVELINO ALVAREZ-ORDÓÑEZ ◽

MARTIN WAGNER ◽

KATHRIN RYCHLI ◽

...

Keyword(s):

Listeria Monocytogenes ◽

Raw Materials ◽

Meat Products ◽

Cross Contamination ◽

Meat Processing ◽

Food Contact ◽

Food Contact Surfaces ◽

Processing Facility ◽

Contact Surfaces ◽

Contamination Routes

Putative routes of Listeria monocytogenes contamination, based on the workflow of the employees, were studied in a meat processing facility by investigating 226 samples collected from food contact surfaces, non–food contact surfaces, raw materials, and ready-to-eat meat products on four occasions over a 1-year period. In total, 19.7% of non–food contact surfaces, 22.9% of food contact surfaces, 45% of raw materials, and 20% of ready-to-eat meat products were positive for L. monocytogenes (analyzed by the International Organization for Standardization standard method ISO 11290). Pulsed-field gel electrophoresis (PFGE) profiles were determined for a representative subset of these isolates, and 11 distinct pulsotypes were identified, two of which were frequently isolated (T4 and T8) and considered persistent. Strains from the various pulsotypes were screened for the presence of bcrABC and qacH, the genes responsible for tolerance responses to quaternary ammonium compounds. Two strains harbored bcrABC, and these strains had a higher benzalkonium chloride tolerance; however, they were not considered persistent strains. The frequently isolated PFGE pulsotype T8 strains were highly adhesive to abiotic surfaces at 10 and 20°C; however, the pulsotype T6 strain, which was isolated only at the last sampling time, had the highest adhesion ability, and the pulsotype T4 strain (the second most persistent pulsotype) had only modest adhesion. Four putative cross-contamination routes were confirmed by mapping the persistent and other isolates. This information could allow a food safety manager to adjust the work flow to improve the hygienic conditions in a meat processing facility. This study revealed the prevalence and persistence of L. monocytogenes strains in a meat processing facility and established the importance of developing strategies to avoid cross-contamination, recalls, and outbreaks of listeriosis.

Download Full-text

Surveillance of listeriosis in the Tel Aviv District, Israel, 2010–2015

Epidemiology and Infection ◽

10.1017/s0950268817003004 ◽

2018 ◽

Vol 146 (3) ◽

pp. 283-290 ◽

Cited By ~ 1

Author(s):

M. Salama ◽

Z. Amitai ◽

A. V. Ezernitchi ◽

R. Sheffer ◽

J. Jaffe ◽

...

Keyword(s):

Public Health ◽

Listeria Monocytogenes ◽

High Risk ◽

Gel Electrophoresis ◽

Invasive Disease ◽

Pulsed Field Gel Electrophoresis ◽

Number Of Clusters ◽

Tel Aviv ◽

Sources Of Infection ◽

Contamination Routes

AbstractThis study analyses the epidemiologic, clinical and molecular findings of all culture-confirmed cases of listeriosis notified from 2010 to 2015 in the Tel Aviv District, which is known to have high rates of listeriosis. All clinical isolates ofListeria monocytogeneswere subtyped using two-enzyme pulsed-field gel electrophoresis. During the studied period, 102 cases of listeriosis were notified, including 23 pregnancy-associated cases (23%). Among 79 non-pregnancy-associated cases, 18 had neuro-invasive disease (21%). There were 26 deaths associated with the disease. Using molecular identification, we found a number of clusters of identical bacterial clones, which pointed to possible sources of infection. The high rates of morbidity and mortality resulting from listeriosis, as well as the diverse ways of infection demonstrated in this study, accentuate the need to boost public health actions, in order to raise awareness and better control high-risk contamination routes.

Download Full-text

Incidence of Listeria monocytogenes and other Listeria spp. in Ewes' Raw Milk

Journal of Food Protection ◽

10.4315/0362-028x-57.7.571 ◽

1994 ◽

Vol 57 (7) ◽

pp. 571-575 ◽

Cited By ~ 21

Author(s):

JOSE L. RODRIGUEZ ◽

PILAR GAVA ◽

MARGARITA MEDINA ◽

MANUEL NUÑEZ

Keyword(s):

Listeria Monocytogenes ◽

Sampling Period ◽

Raw Milk ◽

Seasonal Influence ◽

Listeria Ivanovii ◽

Milk Contamination ◽

One Year ◽

The One ◽

Listeria Seeligeri ◽

Listeria Welshimeri

Ewes' milk samples from 287 farm bulk tanks and 17 transport tankers were analyzed for Listeria over a one-year period. Listeria monocytogenes and Listeria innocua were detected in 2.19% and 2.00% of 1052 farm samples, and in 18.38% and 11.76% of 136 tanker samples, respectively. Incidence of Listeria grayi, Listeria ivanovii, Listeria seeligeri and Listeria welshimeri was under 0.4% in farm samples and under 1% in tanker samples. Most farms (93.38%) produced milk free from L. monocytogenes throughout the one-year sampling period. No seasonal influence on milk contamination by Listeria was found. However, ewes' milk contamination by L. monocytogenes and other Listeria spp. was significantly higher in farms where cows were also reared than in farms where only ewes were present.

Download Full-text

Occurrence, Persistence, and Contamination Routes ofListeria monocytogenesGenotypes on Three Finnish Dairy Cattle Farms: a Longitudinal Study

Applied and Environmental Microbiology ◽

10.1128/aem.02000-17 ◽

2017 ◽

Vol 84 (4) ◽

Cited By ~ 8

Author(s):

Hanna Castro ◽

Anniina Jaakkonen ◽

Marjaana Hakkinen ◽

Hannu Korkeala ◽

Miia Lindström

Keyword(s):

Longitudinal Study ◽

Listeria Monocytogenes ◽

Dairy Cattle ◽

Control Strategies ◽

Dairy Farms ◽

Bulk Tank Milk ◽

Content Type ◽

Bulk Tank ◽

Contamination Routes ◽

Cattle Farms

ABSTRACTThe molecular epidemiology ofListeria monocytogeneswas investigated in a longitudinal study of three Finnish dairy farms during 2013 to 2016. A total of 186 bulk tank milk (BTM), 224 milk filter sock (MFS), and 1,702 barn environment samples were analyzed, and isolates ofL. monocytogeneswere genotyped using pulsed-field gel electrophoresis.L. monocytogenesoccurred throughout the year in all sample types, and the prevalence in MFS increased significantly during the indoor season.L. monocytogeneswas more prevalent in MFS (29%) than in BTM (13%) samples. However, the prevalence ofL. monocytogenesvaried more between farms in samples of MFS (13 to 48%) than in BTM (10 to 16%). For each farm, theL. monocytogenesgenotypes detected were classified by persistence (defined as persistent if isolated from ≥3 samples during ≥6 months) and predominance (defined as predominant if >5% prevalence on at least one farm visit). The prevalence of sporadic genotypes was 4 to 5% on all three farms. In contrast, the prevalence of persistent predominant genotypes varied between farms by 4% to 16%. The highest prevalence of persistent predominant genotypes was observed on the farm with the poorest production hygiene. Persistent predominant genotypes were most prevalent on feeding surfaces, water troughs, and floors. Genotypes isolated from the milking system or from cow udders had a greater relative risk of occurring in BTM and MFS than genotypes that only occurred elsewhere in the farm, supporting the hypothesis thatL. monocytogenes is transmitted to milk from contamination on the udder surface or in the milking equipment.IMPORTANCEListeria monocytogenesis a ubiquitous environmental bacterium and the causative agent of a serious foodborne illness, listeriosis. Dairy products are common vehicles of listeriosis, and dairy cattle farms harborL. monocytogenesgenotypes associated with human listeriosis outbreaks. Indeed, dairy cattle farms act as a reservoir ofL. monocytogenes, and the organism is frequently detected in bulk tank milk (BTM) and in the feces of clinically healthy cows. The ecology ofL. monocytogenesin the farm environment is complex and poorly understood. Isolates of the sameL. monocytogenesgenotype can occur in the farm for years, but the factors contributing to the persistence of genotypes on dairy farms are unknown. Knowledge of the persistence patterns and contamination routes ofL. monocytogeneson dairy farms can improve management of the contamination pressure in the farm environment and aid in the development of focused control strategies to reduce BTM contamination.

Download Full-text