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Schoder D, Pelz A, Paulsen P. Transmission Scenarios of Listeria monocytogenes on Small Ruminant On-Farm Dairies. Foods 2023; 12:foods12020265. [PMID: 36673359 PMCID: PMC9858201 DOI: 10.3390/foods12020265] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 12/19/2022] [Accepted: 12/22/2022] [Indexed: 01/11/2023] Open
Abstract
Listeria monocytogenes can cause severe foodborne infections in humans and invasive diseases in different animal species, especially in small ruminants. Infection of sheep and goats can occur via contaminated feed or through the teat canal. Both infection pathways result in direct (e.g., raw milk from an infected udder or fresh cheese produced from such milk) or indirect exposure of consumers. The majority of dairy farmers produces a high-risk product, namely fresh cheese made from raw ewe's and goat's milk. This, and the fact that L. monocytogenes has an extraordinary viability, poses a significant challenge to on-farm dairies. Yet, surprisingly, almost no scientific studies have been conducted dealing with the hygiene and food safety aspects of directly marketed dairy products. L. monocytogenes prevalence studies on small ruminant on-farm dairies are especially limited. Therefore, it was our aim to focus on three main transmission scenarios of this important major foodborne pathogen: (i) the impact of caprine and ovine listerial mastitis; (ii) the significance of clinical listeriosis and outbreak scenarios; and (iii) the impact of farm management and feeding practices.
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Affiliation(s)
- Dagmar Schoder
- Institute of Food Safety, Food Technology and Veterinary Public Health, Unit of Food Microbiology, University of Veterinary Medicine, Veterinaerplatz 1, 1210 Vienna, Austria
- Vétérinaires sans Frontières Austria, Veterinaerplatz 1, 1210 Vienna, Austria
- Correspondence: ; Tel.: +43-1-25077-3520
| | - Alexandra Pelz
- Vétérinaires sans Frontières Austria, Veterinaerplatz 1, 1210 Vienna, Austria
| | - Peter Paulsen
- Institute of Food Safety, Food Technology and Veterinary Public Health, Unit of Food Hygiene and Technology, University of Veterinary Medicine, Veterinaerplatz 1, 1210 Vienna, Austria
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Schoder D, Guldimann C, Märtlbauer E. Asymptomatic Carriage of Listeria monocytogenes by Animals and Humans and Its Impact on the Food Chain. Foods 2022; 11:3472. [PMID: 36360084 PMCID: PMC9654558 DOI: 10.3390/foods11213472] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 10/11/2022] [Accepted: 10/26/2022] [Indexed: 07/30/2023] Open
Abstract
Humans and animals can become asymptomatic carriers of Listeria monocytogenes and introduce the pathogen into their environment with their feces. In turn, this environmental contamination can become the source of food- and feed-borne illnesses in humans and animals, with the food production chain representing a continuum between the farm environment and human populations that are susceptible to listeriosis. Here, we update a review from 2012 and summarize the current knowledge on the asymptomatic carrier statuses in humans and animals. The data on fecal shedding by species with an impact on the food chain are summarized, and the ways by which asymptomatic carriers contribute to the risk of listeriosis in humans and animals are reviewed.
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Affiliation(s)
- Dagmar Schoder
- Department of Veterinary Public Health and Food Science, Institute of Food Safety, University of Veterinary Medicine, 1210 Vienna, Austria
- Veterinarians without Borders Austria, 1210 Vienna, Austria
| | - Claudia Guldimann
- Department of Veterinary Sciences, Faculty of Veterinary Medicine, Institute of Food Safety and Analytics, Ludwig-Maximilians-University Munich, 85764 Oberschleißheim, Germany
| | - Erwin Märtlbauer
- Department of Veterinary Sciences, Faculty of Veterinary Medicine, Institute of Milk Hygiene, Ludwig-Maximilians-University Munich, 85764 Oberschleißheim, Germany
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3
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Matto C, Varela G, Braga V, Vico V, Gianneechini RE, Rivero R. Detection of Listeria spp. in cattle and environment of pasture-based dairy farms. PESQUISA VETERINÁRIA BRASILEIRA 2018. [DOI: 10.1590/1678-5150-pvb-5663] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
ABSTRACT: The aim of the study was to detect Listeria spp., particularly Listeria monocytogenes, in cattle and environment of pasture based dairy farms in Paysandú, Uruguay. A two-stage sampling was conducted, 10 farms were selected by probability proportional to size. A single visit was made to each farm. Samples from bovine faeces, feedstuffs, bulk tank milk, drinking water and soil from the entry and exit pens of the milking parlour were collected for bacteriological studies. PCR assays were used to confirm species and determine the serotype profile of L. monocytogenes isolates. AscI-pulsed-field gel electrophoresis was done to genetically compare them. Listeria spp. were isolated from eight of ten dairy farms, whereas L. monocytogenes in three of them. Serotype distribution in L. monocytogenes was as follows: 1/2a, three isolates; 4b, one isolate. L. monocytogenes or L. innocua excreted from clinically healthy milking cows was detected via faeces. In feedstuffs, only one L. monocytogenes 1/2a isolate from a pasture was obtained. The strain was identical by PFGE to an isolate 1/2a obtained from a pool of milking cow feces that grazed on this farm. No isolation of Listeria spp. was retrieved from the bulk tank milk or drinking water from any of the farms. Listeria innocua was detected in 13 feedstuffs and seven samples of soil from the entry and exit pens of the milking parlour. This is a first local study that confirms the presence of Listeria spp. including L. monocytogenes in healthy cattle and environment of pasture-based dairy farms. These results suggest the potential role that healthy cattle and their sub-products would play as a source of these agents for humans and/or others animals. More detailed studies that include genetic comparison of human and animal isolates are required in order to clearly establish the epidemiological relationship.
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Bandelj P, Jamnikar‐Ciglenecki U, Ocepek M, Blagus R, Vengust M. Risk factors associated with fecal shedding of Listeria monocytogenes by dairy cows and calves. J Vet Intern Med 2018; 32:1773-1779. [PMID: 30295965 PMCID: PMC6189359 DOI: 10.1111/jvim.15234] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 04/17/2018] [Accepted: 05/07/2018] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Listeria monocytogenes (LM) is an important foodborne pathogen affecting animals and humans. Listeriosis outbreaks in humans caused by consumption of unpasteurized dairy products are of serious concern. OBJECTIVE To determine risk factors associated with fecal shedding of LM in family dairy farms. ANIMALS Fecal samples were collected from cows and calves on 20 family dairy farms in 2-week intervals for a period of 1 year. METHODS Longitudinal study. LM was detected using qPCR. Univariate mixed effect model and multivariate analyses were performed to associate risk factors (dietary change, breed, mastitis, other diseases, antibiotic treatment, other treatments, heat index, and meteorological season) with fecal shedding of LM. RESULTS LM was isolated from all farms on at least 1 sampling day. The average yearly prevalence was 18.2% (98/540) and 8.4% (43/511) in cows and calves, respectively. Heat index (P = .05) and meteorological season (P = .04) affected fecal shedding of LM on a farm level. Meteorological season only influenced fecal shedding of LM in cows (P = .04), whereas heat index (P = .01) influenced fecal shedding of LM in calves. Spring season was identified as the major risk factor associated fecal shedding of LM on a farm level (P = .01) and in cows (P = .01). Dietary changes were associated with lower odds for fecal shedding of LM in calves (P < .01). CONCLUSIONS AND CLINICAL IMPORTANCE Fecal shedding of LM is associated with environmental temperatures and the meteorological season. Farmers and veterinarians should use this information when implementing strategies to reduce risks for LM dissemination in animals and in the community.
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Affiliation(s)
- Petra Bandelj
- Veterinary FacultyUniversity of Ljubljana, Gerbiceva 60LjubljanaSlovenia
| | | | - Matjaz Ocepek
- Veterinary FacultyUniversity of Ljubljana, Gerbiceva 60LjubljanaSlovenia
| | - Rok Blagus
- Institute for Biostatistics and Medical Informatics, Faculty of Medicine, University of Ljubljana, Vrazov trg 2LjubljanaSlovenia
| | - Modest Vengust
- Veterinary FacultyUniversity of Ljubljana, Gerbiceva 60LjubljanaSlovenia
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Lang-Halter E, Schober S, Scherer S. Permanent colonization of creek sediments, creek water and limnic water plants by four Listeria species in low population densities. Z NATURFORSCH C 2016; 71:335-345. [PMID: 27583467 DOI: 10.1515/znc-2016-0114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 07/28/2016] [Indexed: 11/15/2022]
Abstract
During a 1-year longitudinal study, water, sediment and water plants from two creeks and one pond were sampled monthly and analyzed for the presence of Listeria species. A total of 90 % of 30 sediment samples, 84 % of 31 water plant samples and 67 % of 36 water samples were tested positive. Generally, most probable number counts ranged between 1 and 40 g-1, only occasionally >110 cfu g-1 were detected. Species differentiation based on FT-IR spectroscopy and multiplex PCR of a total of 1220 isolates revealed L. innocua (46 %), L. seeligeri (27 %), L. monocytogenes (25 %) and L. ivanovii (2 %). Titers and species compositions were similar during all seasons. While the species distributions in sediments and associated Ranunculus fluitans plants appeared to be similar in both creeks, RAPD typing did not provide conclusive evidence that the populations of these environments were connected. It is concluded that (i) the fresh-water sediments and water plants are year-round populated by Listeria, (ii) no clear preference for growth in habitats as different as sediments and water plants was found and (iii) the RAPD-based intraspecific biodiversity is high compared to the low population density.
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Gröhn YT. Progression to multi-scale models and the application to food system intervention strategies. Prev Vet Med 2014; 118:238-46. [PMID: 25217407 DOI: 10.1016/j.prevetmed.2014.08.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 07/26/2014] [Accepted: 08/20/2014] [Indexed: 01/03/2023]
Abstract
The aim of this article is to discuss how the systems science approach can be used to optimize intervention strategies in food animal systems. It advocates the idea that the challenges of maintaining a safe food supply are best addressed by integrating modeling and mathematics with biological studies critical to formulation of public policy to address these challenges. Much information on the biology and epidemiology of food animal systems has been characterized through single-discipline methods, but until now this information has not been thoroughly utilized in a fully integrated manner. The examples are drawn from our current research. The first, explained in depth, uses clinical mastitis to introduce the concept of dynamic programming to optimize management decisions in dairy cows (also introducing the curse of dimensionality problem). In the second example, a compartmental epidemic model for Johne's disease with different intervention strategies is optimized. The goal of the optimization strategy depends on whether there is a relationship between Johne's and Crohn's disease. If so, optimization is based on eradication of infection; if not, it is based on the cow's performance only (i.e., economic optimization, similar to the mastitis example). The third example focuses on food safety to introduce risk assessment using Listeria monocytogenes and Salmonella Typhimurium. The last example, practical interventions to effectively manage antibiotic resistance in beef and dairy cattle systems, introduces meta-population modeling that accounts for bacterial growth not only in the host (cow), but also in the cow's feed, drinking water and the housing environment. Each example stresses the need to progress toward multi-scale modeling. The article ends with examples of multi-scale systems, from food supply systems to Johne's disease. Reducing the consequences of foodborne illnesses (i.e., minimizing disease occurrence and associated costs) can only occur through an understanding of the system as a whole, including all its complexities. Thus the goal of future research should be to merge disciplines such as molecular biology, applied mathematics and social sciences to gain a better understanding of complex systems such as the food supply chain.
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Affiliation(s)
- Yrjö T Gröhn
- Section of Epidemiology, Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, S3-108 Schurman Hall, Ithaca, NY 14853, USA.
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Ammendolia MG, Iosi F, De Berardis B, Guccione G, Superti F, Conte MP, Longhi C. Listeria monocytogenes behaviour in presence of non-UV-irradiated titanium dioxide nanoparticles. PLoS One 2014; 9:e84986. [PMID: 24416327 PMCID: PMC3887020 DOI: 10.1371/journal.pone.0084986] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Accepted: 11/27/2013] [Indexed: 01/04/2023] Open
Abstract
Listeria monocytogenes is the agent of listeriosis, a food-borne disease. It represents a serious problem for the food industry because of its environmental persistence mainly due to its ability to form biofilm on a variety of surfaces. Microrganisms attached on the surfaces are a potential source of contamination for environment and animals and humans. Titanium dioxide nanoparticles (TiO2 NPs) are used in food industry in a variety of products and it was reported that daily exposure to these nanomaterials is very high. Anti-listerial activity of TiO2 NPs was investigated only with UV-irradiated nanomaterials, based on generation of reactive oxigen species (ROS) with antibacterial effect after UV exposure. Since both Listeria monocytogenes and TiO2 NPs are veicolated with foods, this study explores the interaction between Listeria monocytogenes and non UV-irradiated TiO2 NPs, with special focus on biofilm formation and intestinal cell interaction. Scanning electron microscopy and quantitative measurements of biofilm mass indicate that NPs influence both production and structural architecture of listerial biofilm. Moreover, TiO2 NPs show to interfere with bacterial interaction to intestinal cells. Increased biofilm production due to TiO2 NPs exposure may favour bacterial survival in environment and its transmission to animal and human hosts.
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Affiliation(s)
| | - Francesca Iosi
- Department of Technology and Health, Istituto Superiore di Sanità, Rome, Italy
| | - Barbara De Berardis
- Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Rome, Italy
| | - Giuliana Guccione
- Department of Public Health and Infectious Diseases, “Sapienza” University of Rome, Rome, Italy
| | - Fabiana Superti
- Department of Technology and Health, Istituto Superiore di Sanità, Rome, Italy
| | - Maria Pia Conte
- Department of Public Health and Infectious Diseases, “Sapienza” University of Rome, Rome, Italy
| | - Catia Longhi
- Department of Public Health and Infectious Diseases, “Sapienza” University of Rome, Rome, Italy
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Ivanek R, Österberg J, Gautam R, Sternberg Lewerin S. Salmonella fecal shedding and immune responses are dose- and serotype- dependent in pigs. PLoS One 2012; 7:e34660. [PMID: 22523553 PMCID: PMC3327719 DOI: 10.1371/journal.pone.0034660] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Accepted: 03/08/2012] [Indexed: 11/18/2022] Open
Abstract
Despite the public health importance of Salmonella infection in pigs, little is known about the associated dynamics of fecal shedding and immunity. In this study, we investigated the transitions of pigs through the states of Salmonella fecal shedding and immune response post-Salmonella inoculation as affected by the challenge dose and serotype. Continuous-time multistate Markov models were developed using published experimental data. The model for shedding had four transient states, of which two were shedding (continuous and intermittent shedding) and two non-shedding (latency and intermittent non-shedding), and one absorbing state representing permanent cessation of shedding. The immune response model had two transient states representing responses below and above the seroconversion level. The effects of two doses [low (0.65×106 CFU/pig) and high (0.65×109 CFU/pig)] and four serotypes (Salmonella Yoruba, Salmonella Cubana, Salmonella Typhimurium, and Salmonella Derby) on the models' transition intensities were evaluated using a proportional intensities model. Results indicated statistically significant effects of the challenge dose and serotype on the dynamics of shedding and immune response. The time spent in the specific states was also estimated. Continuous shedding was on average 10–26 days longer, while intermittent non-shedding was 2–4 days shorter, in pigs challenged with the high compared to low dose. Interestingly, among pigs challenged with the high dose, the continuous and intermittent shedding states were on average up to 10–17 and 3–4 days longer, respectively, in pigs infected with S. Cubana compared to the other three serotypes. Pigs challenged with the high dose of S. Typhimurium or S. Derby seroconverted on average up to 8–11 days faster compared to the low dose. These findings highlight that Salmonella fecal shedding and immune response following Salmonella challenge are dose- and serotype-dependent and that the detection of specific Salmonella strains and immune responses in pigs are time-sensitive.
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Affiliation(s)
- Renata Ivanek
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, United States of America.
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9
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Gautam R, Kulow M, Döpfer D, Kaspar C, Gonzales T, Pertzborn K, Carroll R, Grant W, Ivanek R. The strain-specific dynamics of Escherichia coli O157:H7 faecal shedding in cattle post inoculation. JOURNAL OF BIOLOGICAL DYNAMICS 2012; 6:1052-1066. [PMID: 22988977 PMCID: PMC3983691 DOI: 10.1080/17513758.2012.722232] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
This study reports analysis of faecal shedding dynamics in cattle for three Escherichia coli O157:H7 (ECO157) strains (S1, S2 and S3) of different genotype and ecological history, using experimental inoculation data. The three strains were compared for their shedding frequency and level of ECO157 in faeces. A multistate Markov chain model was used to compare shedding patterns of S1 and S2. Strains S1 and S2 were detected seven to eight times more often and at 10(4) larger levels than strain S3. Strains S1 and S2 had similar frequencies and levels of shedding. However, the total time spent in the shedding state during colonization was on average four times longer for S1 (15 days) compared to S2 (4 days). These results indicate that an ECO157 strain effect on the frequency, level, pattern and the duration of faecal shedding may need to be considered in control of ECO157 in the cattle reservoir.
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Affiliation(s)
- R. Gautam
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
| | - M. Kulow
- School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA
| | - D. Döpfer
- School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA
| | - C. Kaspar
- Department of Bacteriology, University of Wisconsin, Madison, WI 53706, USA
| | - T. Gonzales
- School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA
| | - K.M. Pertzborn
- School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA
| | - R.J. Carroll
- Department of Statistics, Texas A&M University, College Station, TX 77843, USA
| | - W. Grant
- Department of Wildlife and Fisheries Sciences, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX 77843, USA
| | - R. Ivanek
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
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10
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Effectiveness of environmental decontamination as an infection control measure. Epidemiol Infect 2011; 140:542-53. [DOI: 10.1017/s0950268811000604] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
SUMMARYThe effectiveness of environmental decontamination (ED) as a measure in the control of infectious diseases is controversial. This work quantifies the effectiveness of ED by analysing the transmission of pathogens from the environment to susceptible hosts in a Susceptible–Infected–Susceptible model. Analysis of the model shows that ED can render a population disease-free only when the duration of infection (D) is within a certain range. As host-to-host transmission rate is increased,Dfalls outside this range and the higher levels of ED have a diminishing return in reducing the number of infected hosts at endemic equilibrium. To avoid this, ED can be combined with other control measures, such as treating infected individuals to push the duration of infection into the specified range. We propose decision criteria and minimum ED efforts required for control policies to be effective.
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Lanzas C, Ayscue P, Ivanek R, Gröhn YT. Model or meal? Farm animal populations as models for infectious diseases of humans. Nat Rev Microbiol 2010; 8:139-48. [PMID: 20040917 PMCID: PMC7097165 DOI: 10.1038/nrmicro2268] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In recent decades, theory addressing the processes that underlie the dynamics of infectious diseases has progressed considerably. Unfortunately, the availability of empirical data to evaluate these theories has not grown at the same pace. Although laboratory animals have been widely used as models at the organism level, they have been less appropriate for addressing issues at the population level. However, farm animal populations can provide empirical models to study infectious diseases at the population level.
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Affiliation(s)
- Cristina Lanzas
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853, USA.
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12
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Ivanek R, Gröhn YT, Wells MT, Lembo AJ, Sauders BD, Wiedmann M. Modeling of spatially referenced environmental and meteorological factors influencing the probability of Listeria species isolation from natural environments. Appl Environ Microbiol 2009; 75:5893-909. [PMID: 19648372 PMCID: PMC2747854 DOI: 10.1128/aem.02757-08] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Accepted: 07/22/2009] [Indexed: 11/20/2022] Open
Abstract
Many pathogens have the ability to survive and multiply in abiotic environments, representing a possible reservoir and source of human and animal exposure. Our objective was to develop a methodological framework to study spatially explicit environmental and meteorological factors affecting the probability of pathogen isolation from a location. Isolation of Listeria spp. from the natural environment was used as a model system. Logistic regression and classification tree methods were applied, and their predictive performances were compared. Analyses revealed that precipitation and occurrence of alternating freezing and thawing temperatures prior to sample collection, loam soil, water storage to a soil depth of 50 cm, slope gradient, and cardinal direction to the north are key predictors for isolation of Listeria spp. from a spatial location. Different combinations of factors affected the probability of isolation of Listeria spp. from the soil, vegetation, and water layers of a location, indicating that the three layers represent different ecological niches for Listeria spp. The predictive power of classification trees was comparable to that of logistic regression. However, the former were easier to interpret, making them more appealing for field applications. Our study demonstrates how the analysis of a pathogen's spatial distribution improves understanding of the predictors of the pathogen's presence in a particular location and could be used to propose novel control strategies to reduce human and animal environmental exposure.
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Affiliation(s)
- R Ivanek
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843-4458, USA.
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13
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Gröhn Y, Hertl J, Ivanek R, Abou-Zeid K, Wiedmann M. How University Researchers Can Contribute to Farm-to-Table Risk Assessments:Listeria monocytogenesas an Example. Foodborne Pathog Dis 2007; 4:527-37. [DOI: 10.1089/fpd.2007.0012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Yrjö Gröhn
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York
| | - Julia Hertl
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York
| | - Renata Ivanek
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York
| | - Khaled Abou-Zeid
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York
| | - Martin Wiedmann
- Department of Food Science, College of Agriculture and Life Sciences, Cornell University, Ithaca, New York
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Ho AJ, Ivanek R, Gröhn YT, Nightingale KK, Wiedmann M. Listeria monocytogenes fecal shedding in dairy cattle shows high levels of day-to-day variation and includes outbreaks and sporadic cases of shedding of specific L. monocytogenes subtypes. Prev Vet Med 2007; 80:287-305. [PMID: 17481754 DOI: 10.1016/j.prevetmed.2007.03.005] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2006] [Revised: 02/14/2007] [Accepted: 03/20/2007] [Indexed: 10/23/2022]
Abstract
Fecal shedding of Listeria monocytogenes poses a risk for contamination of animal feed and agricultural environments and raw food at the pre-harvest stages of food production. To be able to reduce these risks it is critical to improve understanding of the epidemiology of L. monocytogenes shedding in feces. The objective of this study was to assess the daily variability of fecal shedding and its association with individual animal (lactation number and the day of current lactation) and environmental (feed) risk factors. That was achieved by application of longitudinal daily sample collection in a herd of dairy cattle and molecular characterization of isolated L. monocytogenes. Fecal samples (25) and silage samples (2) were collected daily during two 2-week periods and one 5-day period. L. monocytogenes was isolated from 255 out of 825 (31%) fecal samples on 24 out of 33 (73%) days, and from 25 out of 66 (38%) silage samples on 16 out of 33 (48%) days. Ninety-four percent of cows excreted L. monocytogenes in feces at least once during the study period. Our data analyses indicated that (i) the prevalence and incidence risk of L. monocytogenes fecal shedding in cattle vary considerably over time, from 0 to 100%, and both are associated with contamination of silage, (ii) L. monocytogenes fecal shedding in cattle could occur as part of an outbreak or as an isolated sporadic case, (iii) L. monocytogenes subtypes associated with human infections are commonly isolated from cattle feces and silage, and (iv) a single cow can harbor more than one L. monocytogenes subtype on any given day. Although limited to a single dairy cattle herd, these findings provide a significant advancement in the understanding of the epidemiology of L. monocytogenes fecal shedding in dairy cattle.
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Affiliation(s)
- A J Ho
- Department of Food Science, 412 Stocking Hall, Cornell University, Ithaca, NY 14853, USA
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