Ecology and Transmission ofListeria monocytogenesInfecting Ruminants and in the Farm Environment

Abstract

A case-control study involving 24 case farms with at least one recent case of listeriosis and 28 matched control farms with no listeriosis cases was conducted to probe the transmission and ecology of Listeria monocytogenes on farms. A total of 528 fecal, 516 feed, and 1,012 environmental soil and water samples were cultured for L. monocytogenes. While the overall prevalence of L. monocytogenes in cattle case farms (24.4%) was similar to that in control farms (20.2%), small-ruminant (goat and sheep) farms showed a significantly (P < 0.0001) higher prevalence in case farms (32.9%) than in control farms (5.9%). EcoRI ribotyping of clinical (n ‫؍‬ 17) and farm (n ‫؍‬ 414) isolates differentiated 51 ribotypes. L. monocytogenes ribotypes isolated from clinical cases and fecal samples were more frequent in environmental than in feed samples, indicating that infected animals may contribute to L. monocytogenes dispersal into the farm environment. Ribotype DUP-1038B was significantly (P < 0.05) associated with fecal samples compared with farm environment and animal feedstuff samples. Ribotype DUP-1045A was significantly (P < 0.05) associated with soil compared to feces and with control farms compared to case farms. Our data indicate that (i) the epidemiology and transmission of L. monocytogenes differ between small-ruminant and cattle farms; (ii) cattle contribute to amplification and dispersal of L. monocytogenes into the farm environment, (iii) the bovine farm ecosystem maintains a high prevalence of L. monocytogenes, including subtypes linked to human listeriosis cases and outbreaks, and (iv) L. monocytogenes subtypes may differ in their abilities to infect animals and to survive in farm environments.

Listeria monocytogenes infection in ruminants: Is there a link to the environment, food and human health? A review

“…Moreover, the impact of farming practices on the prevalence of L. monocytogenes has not yet been elucidated. Generally, it has been found that bovine farm environments yield a particularly high prevalence of L. monocytogenes, including subtypes linked to human listeriosis cases and outbreaks (Nightingale et al, 2004). In contrast to small ruminants, cattle appear to contribute to the amplification and spread of L. monocytogenes in the farm environment, which suggests that the epidemiology and transmission of L. monocytogenes could differ between ruminant species (Nightingale et al, 2004;Oliver et al, 2005).…”

“…Generally, it has been found that bovine farm environments yield a particularly high prevalence of L. monocytogenes, including subtypes linked to human listeriosis cases and outbreaks (Nightingale et al, 2004). In contrast to small ruminants, cattle appear to contribute to the amplification and spread of L. monocytogenes in the farm environment, which suggests that the epidemiology and transmission of L. monocytogenes could differ between ruminant species (Nightingale et al, 2004;Oliver et al, 2005). L. monocytogenes in cattle farms has a seasonality pattern with higher environmental isolation rates in spring possibly as a consequence of a combination of winter livestock housing, silage feeding and spring application of manure (Wilkes et al, 2011).…”

“…monocytogenes is characterized by a high genetic diversity and comprises numerous strains, which have diversified into four evolutionary lineages (Ragon et al, 2008;Orsi et al, 2011). There are indications of interstrain differences regarding virulence and transmission (Nightingale et al, 2004;Hain et al, 2007;Ragon et al, 2008). Serotyping was the first method developed for subtype discrimination of L. monocytogenes and has uncovered that the vast majority of human and animal infections are caused by only three different serotypes: 1/2a, 1/2b, and 4b (Okwumabua et al, 2005;Gianfranceschi et al, 2009;Lopez-Valladares et al, 2014;).…”

Listeria monocytogenes en manipuladores de alimentos: un nuevo enfoque para tener en cuenta en los peligros de la industria alimentaria

“…Listeria monocytogenes, además de causar graves infecciones en los seres humanos, también se encuentra causando enfermedad invasiva en muchas especies de diferentes de animales, incluidos los rumiantes de granja, como vacas, ovejas y cabras (7). Varios productos alimenticios derivados de estos animales, han sido frecuentemente implicados como fuentes de casos y brotes de listeriosis en humanos (8), ya que el microorganismo presente en las materias primas se puede inactivar eficazmente por las combinaciones de tiempo y temperatura típicas para la producción de alimentos más procesados (por ejemplo, leche pasteurizada), pero es difícil de manejar en productos alimenticios listos para el consumo, los cuales sufren contaminación cruzada con elementos contaminados del entorno de la planta de procesamiento (9) o con las manos de los manipuladores durante el proceso de producción, lo cual se constituye como la primera causa de (10).…”

Invasiveness of Listeria monocytogenes strains isolated from animals in Poland

“…Food contamination usually occurs by cross-contamination of the final product by L. monocytogenes present in food processing plant environments. Despite infected animals are infrequently linked to human infections, animal-derived food products not processed before consumption, as well as raw food of plant origin contaminated by manure from infected or shedding animals can directly cause human listeriosis (Nightingale et al 2004).…”