Subject(s)
Humans , Animals , Food Microbiology , Listeriosis/microbiology , Listeria monocytogenes/isolation & purification , Polymorphism, Restriction Fragment Length , DNA, Bacterial/genetics , Cattle , Serotyping , Chickens , Disease Outbreaks , Bacterial Typing Techniques , Listeriosis/prevention & control , Listeriosis/transmission , Listeriosis/epidemiology , Listeria monocytogenes/classification , Listeria monocytogenes/genetics , Meat/microbiology , Meat Products/microbiology , MexicoABSTRACT
La listeriosis es una enfermedad transmitida por alimentos (ETA) y ocasionada por Listeria monocytogenes. La importancia de ésta se debe a su impacto clínico, la alta tasa de mortalidad y el efecto económico derivado de los brotes asociados con el consumo de alimentos. En México, las fallas en los sistemas de vigilancia epidemiológicos son causa de información imprecisa sobre la incidencia de la listeriosis y sobre su caracterización como ETA. En este trabajo se presentan datos referentes a la presencia de la bacteria en alimentos, reportes de casos de la enfermedad y patologías relacionadas con infección por L. monocytogenes. La falta de datos exactos sobre la importancia de esta bacteria plantea la necesidad de concientizar a las instancias correspondientes para definir estrategias de búsqueda intencionada de L. monocytogenes en alimentos y de la recopilación de información clínica precisa que permita conocer la importancia clínica y epidemiológica de la listeriosis en México.
Listeriosis is caused by Listeria monocytogenes, an important food-borne disease due to its clinical forms, high mortality rate, and the economic impact in both clinical and food production industries. In Mexico, the lack of epidemiological surveillance systems leads to the need of accurate data on the incidence of listeriosis and its association with food-borne disease. In this paper, we present data about the presence of this bacterium in food, reports related to clinical cases of listeriosis, and information of diseases in which L. monocytogenes may be involved. However, in most of these cases the etiology was not established. Given this, there's a need to inform and warn the appropriate entities, to define strategies for the mandatory search of L. monocytogenes through the whole food production chain and clinical suspects, for the epidemiological importance and control of listeriosis in Mexico.
Subject(s)
Animals , Cysteine Endopeptidases/isolation & purification , Egg Proteins/metabolism , Enzyme Precursors/isolation & purification , Antimalarials/pharmacology , Chromatography, Gel , Cysteine Endopeptidases/metabolism , Cysteine Proteinase Inhibitors/pharmacology , Egg Yolk/chemistry , Electrophoresis, Polyacrylamide Gel , Enzyme Activation , Enzyme Precursors/metabolism , Hydrogen-Ion Concentration , Leucine/analogs & derivatives , Leucine/metabolism , Molecular Weight , OrthopteraABSTRACT
The microbiological quality of raw meat was evaluated in 18 retail units of the municipal market in Culiacan, Sinaloa. The levels of E. coli were measured using methods from the Bacteriological Analytical Manual, and the O157 sero-group and the H7 antigen were also evaluated using chromogenic media and PCR, respectively. The results were confirmed using real time-PCR (PCR-TR) and PCR to detect virulence genes (vt1, vt2, eaeA and hlyA). Of the samples tested, 31.5% were positive for E. coli, with concentrations between 100 and 700 CFU/g of beef. Nine suspected E. coli O157:H7 strains were isolated from 16 samples, which were then discarded by the PCR-TR test. The virulence genes were not detected. The microbial contamination of beef could indicate the presence of pathogens from fecal sources. To guarantee the quality of these products, it is important to incorporate food safety programs.
Se evaluó la calidad microbiológica de carne de res en 18 comercios del mercado municipal de Culiacán, Sinaloa. Para determinar E. coli se usó la metodología del Manual Bacteriológico Analítico, y para evaluar el serogrupo O157 y antígeno H7, se usaron medios cromogénicos y PCR, respectivamente. La confirmación se hizo por PCR tiempo real (PCR-TR) y la detección de genes de virulencia (vt1, vt, eaeA y hlyA), por PCR. El 31.5% de muestras resultaron positivas para E. coli, con concentraciones entre 100 y 700 UFC/g. Se aislaron nueve cepas presuntivas de E. coliO157:H7 de 16 muestras, las cuales fueron descartadas con la técnica PCR-TR. No se detectaron genes de virulencia. La contaminación microbiana de la carne de res podría indicar la presencia de patógenos provenientes de fuentes fecales. Por ello es importante incorporar programas de inocuidad para garantizar la calidad de estos productos.