Objective. To identify dietary risk factors for sporadic listeriosis. Design. Case-control study with blinded telephone interviews. Setting. Multistate population of 18 million persons, November 1988 ...through December 1990. Participants. One hundred sixty-five patients with culture-confirmed listeriosis and 376 control subjects matched for age, health care provider, and immunosuppressive condition. Results. The annual incidence of invasive listeriosis was 7.4 cases per million population; 23% of the infections were fatal. Cases were more likely than matched controls to have eaten soft cheeses (odds ratio OR, 2.6; 95% confidence interval CI, 1.4 to 4.8; P = 0.002) or food purchased from store delicatessen counters (OR, 1.6; 95% CI, 1.0 to 2.5; P = 0.04); 32% of sporadic disease could be attributed to eating these foods. Sixty-nine percent of cases in men and nonpregnant women occurred in cancer patients, persons with the acquired immunodeficiency syndrome, organ transplant recipients, or those receiving corticosteroid therapy. Among these immunosuppressed patients, eating undercooked chicken also increased the risk of listeriosis (OR, 3.3; 95% CI, 1.2 to 9.2; P = 0.02). Conclusions. Foodborne transmission may account for a substantial portion of sporadic listeriosis. Prevention efforts should include dietary counseling of high-risk patients and continued monitoring of food production
Ribotyping was compared with multilocus enzyme electrophoresis (MEE) for subtyping 305 Listeria monocytogenes isolates from clinical and nonclinical sources. For ribotyping, EcoRI-restricted genomic ...DNA fragments of L. monocytogenes strains were separated by agarose gel electrophoresis, and Southern blots were probed with a cloned Escherichia coli rrnB operon (plasmid pKK3535) labeled with digoxigenin. The L. monocytogenes isolates were divided into 28 distinct ribotypes, while MEE analysis divided the same isolates into 78 electrophoretic types (ETs). On the basis of their ribotype profiles, the strains were divided into two subgroups. The ribotype alpha (RT alpha) subgroup contained serotypes 1/2a, 1/2c, and 3a, and the ribotype beta (RT beta) subgroup contained serotypes 1/2b, 3b, 4b, and 4ab. This division is in complete agreement with MEE analysis, which divides the species into two subgroups (ET groups A and B), with the same serotype distribution in each subgroup. Overall, MEE was more discriminating than ribotyping. However, in several instances ribotyping discriminated between isolates within the same ET. Ribotyping was more discriminating for serotypes 1/2a, 1/2c, and 3a (Simpson's Index for Diversity DI = 0.81) than for serotypes 1/2b and 4b (DI = 0.76). A substantial proportion (69%) of serotype 1/2b and 4b strains clustered in five ETs and five ribotypes. These data suggest that ribotyping and MEE do not provide adequate discrimination between strains of serotypes 1/2b and 4b. Methods such as pulsed-field gel electrophoresis and random amplified polymorphic DNA analysis should be explored for further discrimination of strains of these serotypes
A facility which produced turkey franks that had been microbiologically linked to a case of human listeriosis was evaluated to establish prevalence of contamination and identify potential points for ...intervention. Listeria monocytogenes was isolated from only two of 41 environmental samples obtained in the plant. Among production line product samples analyzed by the Centers for Disease Control, 0 to 8% of samples from the production stages before the peeler-conveyor belt apparatus were positive for the case strain of L. monocytogenes, whereas 12 of 14 (86%) samples collected from this apparatus were positive (p 0.001). The most probable number (MPN) of L. monocytogenes in finished product purchased from a retail outlet was less than 0.3 per gram; however, the opened package of franks from the case patient's refrigerator had an MPN of 1100 per gram. These data suggest that systematic culturing and analysis of products and production facilities may help identify appropriate interventions to reduce L. monocytogenes contamination in food processing plants and contribute to control of L. monocytogenes in ready-to-eat meat products
We compared the cold enrichment (CE) and U.S. Department of Agriculture (USDA) methods for isolating Listeria monocytogenes by examining 402 food samples. The food samples were collected from ...refrigerators of listeriosis patients as part of a multistate active surveillance project to determine the role of foods in sporadic listeriosis in the United States. L. monocytogenes was isolated from 51 food samples (13%). The USDA method was significantly better (P 0.001) than the CE method. The isolation efficiencies of the USDA and CE methods were 96 and 59%, respectively. Quantitation of L. monocytogenes in the food samples revealed that many food samples containing 0.3 CFU/g were negative as determined by the CE method but positive as determined by the USDA method
Reduction in the incidence of human listeriosis in the United States Tappero, J.W. (Centers for Disease Control and Prevention, Atlanta, GA.); Schuchat, A; Deaver, K.A ...
JAMA : the journal of the American Medical Association,
(12 Apr 1995), Letnik:
273, Številka:
14
Journal Article
Recenzirano
Background. Food-borne transmission is now recognized as a major cause of human listeriosis. Objective. To assess the impact of prevention efforts, listeriosis rates before interventions were ...initiated in 1989 were compared with more recent rates (1990 through 1993). Design. From 1989 through 1993, multistate, laboratory-based active surveillance was conducted to identify all cases in which Listeria monocytogenes was isolated from cultures or ordinarily sterile sites in an aggregate population of more than 19 million. Setting. All laboratories serving acute care hospitals in up to nine surveillance areas in the United States. Interventions. In 1989, a well-publicized case report of listeriosis linked to processed poultry led US regulatory agencies to enforce aggressive food monitoring policies and prompted industry to invest in cleanup efforts. In May 1992, consumer guidelines for listeriosis prevention were disseminated. Outcome Measures. Cases of perinatal and nonperinatal listeriosis. Results. The rate of listeriosis decreased in all surveillance areas. Projection of these rates to the US population suggests an estimated 1965 cases and 481 deaths occurred in 1989 compared with an estimated 1092 cases and 248 deaths in 1993, a 44% and 48% reduction in illness and death, respectively. Among adults 50 years of age and older, rates declined from 16.2 per 1 million in 1989 to 10.2 per 1 million in 1993 (P=.02). Perinatal disease decreased from 17.4 cases per 100 000 births in 1989 to 8.6 cases per 100 000 births in 1993 (P=.003). Three serotypes (1/2a, 1/2b, and 4b) of L monocytogenes accounted for more than 96% of cases during each year of the study (1989 through 1993) Conclusions. The incidence of listeriosis in study areas was substantially lower in 1993 than in 1989. The temporal association of this reduction with industry, regulatory, and educational efforts suggests these measures were effective
Objective. To evaluate the role of foods in sporadic listeriosis. Design. Microbiologic survey of foods collected from refrigerators of patients with listeriosis identified through active ...laboratory-based surveillance. Patient and food Listeria monocytogenes isolates were subtyped to identify foods contaminated with the same strain of L monocytogenes that caused illness in the patient; samples of these foods were obtained from the retail source. Setting. Multistate population-based study conducted between 1988 and 1990. Results. Listeria monocytogenes grew from at least one food specimen in the refrigerators of 79 (64%) of 123 listeriosis patients; 11% of more than 2000 food specimens collected in the study contained L monocytogenes. Twenty-six (33%) of 79 refrigerators with foods that grew L monocytogenes contained at least one food isolate of the same strain as that in the corresponding patient, a frequency much higher than would be expected by chance (P<.001). Multivariate analysis showed that of the food specimens that grew L monocytogenes, foods that were ready-to-eat, foods that grew L monocytogenes by a direct-plating method (a measure of the level of contamination), and foods that contained serotype 4b isolates were independently associated with an increased likelihood of containing the patient-matching strain. Conclusion. We identified specific food and L monocytogenes isolate characteristics--ready-to-eat foods, foods containing higher concentrations of L monocytogenes, and foods containing serotype 4b--which were associated with disease-causing strains. These results can provide guidance to industry and regulatory agencies in developing strategies to prevent listeriosis.
A facility which produced turkey franks that had been microbiologically linked to a case of human listeriosis was evaluated to establish prevalence of contamination and identify potential points for ...intervention. Listeria monocytogenes was isolated from only two of 41 environmental samples obtained in the plant. Among production line product samples analyzed by the Centers for Disease Control, 0 to 8% of samples from the production stages before the peeler-conveyor belt apparatus were positive for the case strain of L. monocytogenes, whereas 12 of 14 (86%) samples collected from this apparatus were positive (p 0.001). The most probable number (MPN) of L. monocytogenes in finished product purchased from a retail outlet was less than 0.3 per gram; however, the opened package of franks from the case patient's refrigerator had an MPN of 1100 per gram. These data suggest that systematic culturing and analysis of products and production facilities may help identify appropriate interventions to reduce L. monocytogenes contamination in food processing plants and contribute to control of L. monocytogenes in ready-to-eat meat products
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