Listeria monocytogenes en repollo y lechuga como vehículos de transmisión de listeriosis humana. mercados la hermelinda, central y palermo de Trujillo, Perú. 2006 – 2007

• Autor: Martín Alva, Enrique Aurelio
• Formato: tesis doctoral
• Fecha de Publicación: 2007
• Institución: Universidad Nacional de Trujillo
• Repositorio: UNITRU-Tesis
• Lenguaje: español
• OAI Identifier: oai:dspace.unitru.edu.pe:20.500.14414/5786
• Enlace del recurso: https://hdl.handle.net/20.500.14414/5786
• Nivel de acceso: acceso abierto
• Materia: Listeria monocytogenes, Repollo, Lechuga, Transmisión

Listeria monocytogenes is widely distributed in nature, and is one of the most important pathogens of feeding source. The most common transition of this bacteria from the environment to humans; including among others, raw vegetables, like lettuce and cabbage; presuming that the contamination of these is due to the miss-manipulation and control of the same; this is the reason for which it is expected that when such products arrive to the consumer, they have a high frequency of this bacteria; and, consequently, become a means of transportation of the pathogen, for which the following problem is stated: what is the frequency of isolation of Listeria monocytogenes in cabbage and lettuce that are distributed in the markets “La Hermelinda”, “Central” and “Palermo” in Trujillo City as means of transportation of the human listeriosis?.Holding the hypothesis: “the frequency of isolation of this bacteria in such vegetables that are distributed in the markets of Trujillo, is higher that zero”. And the objectives: determine the presence of this bacteria in the vegetables that are the object of study; estimate the frequency of isolation on the evaluated vegetables; and determine the existence of differences on the frequency of isolation of the bacteria, between the cabbage and the lettuce among the markets that are object of study. For such purpose, a close investigation has been applied with observational and transversal study; and a design of stratified, aleatory and multi-staged sample design.The size of the sample (n = 54) was determined with the formula of proportions for finite population and unknown variance; and after that, proceeding with a proportional delivery of the sample among the three markets; being half of it cabbage and the other, lettuce. All the isolated crops were identified by the Automated System Micro Scam Walk Away and by the Molecular Characterization. The difference of frequencies was tested by the Test of Proportions, with a = 0.05. The results confirm the presence of bacteria in these vegetables and from the 54 samples, 12 are positive (22.22%). The presence of bacteria in lettuce for each market is 16.67%; and statistics show that presence of the bacteria in the cabbage is the same in the three markets, but less than in lettuce. The presence of the bacteria implies that it is present in the rest of the markets of the city and possibly in other products as well. Besides its presence is highly probable in the salads prepared with other vegetables; for which it is suggested to implement a regular screening of this enteropathogen in our public health system.