Tesis doctoral de Victoria Eugenia Garrido González
Quantitative microbiological risk assessment: listeriosis and ready-to-eat products approach risk assessment is a basis to select risk management measures for food trade at national and international levels, avoiding risk to the population. In recent years, l. Monocytogenes has emerged as an important food safety concern due to the increase of available foods that are susceptible to being contaminated with the pathogen, such as ready-to-eat products (rte) which do not require cooking before consumption, and with special incidence among susceptible population groups (elderly, immunocompromised people and pregnant women). Due to the rare development of quantitative microbiological risk assessment (qmra) in spain, the main objective of this work was to develop a listeriosis risk model at a regional level, following the steps of hazard identification, hazard characterization, exposure assessment and risk characterization in order to better understand the dimension of this public health concern and to carry out future microbiological risk assessment on a national level. the baseline model that was developed describes the probability of suffering listeriosis by consumption of rte smoked fish and sliced cooked meat, taking into account the probability of pathogen growth from the point of sale to the time of consumption. Primary data needed for developing the model was collected from different studies and surveys carried out in navarra between 2003 and 2007. The average rate of listeriosis was 0.9/100.000 inhabitants, with aged people -more than 60 years old (46.4%)- and pregnant women (39.3%) the largest groups affected. Smoked fish was the product most frequently contaminated with the pathogen (25% positive samples), followed by in-store packaged deli meat (8.5%). In addition, these latter products were highly consumed in navarra (76.7% of those interviewed), especially by women and by the oldest population. More than 69.7% of home refrigerators showed temperatures higher than 6ºc, allowing rapid pathogen growth during storage. The final output of the model was the number of cases of listeriosis per year, estimated in 1 case by the consumption of non-prepackaged ham. Reducing temperature storage to below 4ºc throughout the food chain (including storage at home) has been shown to be the best tool for decreasing the risk of listeriosis. due to general acceptance of over-the-counter sliced cooked ham among the population, it is necessary that consumers be informed concerning the risk of listeriosis and the efficient measures that should be taken in order to prevent it, putting special emphasis on the groups comprised of aged population and pregnant women. Taking into account the observed increase of illness in this last group, it is necessary to improve early diagnosis by evaluation of gastrointestinal and feverish episodes in pregnancy cases.
Datos académicos de la tesis doctoral «Valoración cuantitativa de riesgos microbiológicos: aplicación a listeriosis y alimentos listos para consumo.«
- Título de la tesis: Valoración cuantitativa de riesgos microbiológicos: aplicación a listeriosis y alimentos listos para consumo.
- Autor: Victoria Eugenia Garrido González
- Universidad: Navarra
- Fecha de lectura de la tesis: 23/01/2009
Dirección y tribunal
- Director de la tesis
- María Isabel García Jalón De La Lama
- Tribunal
- Presidente del tribunal: moez Sanaa
- stephen john Coupe (vocal)
- Francisco Ballester muñoz (vocal)
- José Luis Berne valero (vocal)