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A 69-year old Caucasian man was admitted to Aarhus University Hospital, Aarhus, Denmark, in a state of reduced consciousness and Glasgow Coma Scale (GCS) score of 13-14. Approximately 4.5 hours [...]

Salmonella enterica, the cause of food poisoning and typhoid fever, has evolved sophisticated mechanisms to modulate Rho family guanosine triphosphatases (GTPases) to mediate specific cellular responses such as actin remodeling, macropinocytosis, and nuclear responses. These responses are largely the result of the activity of a set of bacterial proteins (SopE, SopE2, and SopB) that, upon delivery into host cells via a type III secretion system, activate specific Rho family GTPases either directly (SopE and SopE2) or indirectly (SopB) through the stimulation of an endogenous exchange factor. We show that different Rho family GTPases play a distinct role in Salmonella-induced cellular responses. In addition, we report that SopB stimulates cellular responses by activating SH3-containing guanine nucleotide exchange factor (SGEF), an exchange factor for RhoG, which we found plays a central role in the actin cytoskeleton remodeling stimulated by Salmonella. These results reveal a remarkable level of complexity in the manipulation of Rho family GTPases by a bacterial pathogen.

Escherichia coli (E.coli) O157:H7 was identified as an agent that caused gastrointestinal illness in 1982. Riley et al. reported two outbreaks in Oregon and Michigan that affected 47 individuals and […]

Foodborne botulism, a potentially lethal neuroparalytic disease, is caused by ingesting preformed Clostridium botulinum neurotoxin. We reviewed surveillance data and reports from 1990 to 2000. Of 263 cases from 160 [...]

Foodborne botulism is a potentially fatal, paralytic illness that can cause large outbreaks. A possible increase in botulism incidence during 2001 in the Republic of Georgia prompted this study. We [...]

The socio-political context of modern environmental health disasters tends to be defined as being outside the scope of official public health and epidemiological investigations into the causes of such disasters. On the other hand, popular accounts of these disasters tend to focus exclusively on the role of particular individuals and/or political actors, while minimizing the role of ecological factors. It is argued that an exclusive focus on either set of causal factors gives an incomplete or distorted picture of the origins of an environmental health disaster. In this paper, a socio-ecological analysis is developed to demonstrate how the largest outbreak of waterborne E. coli O157:H7 in Canadian history was the emergent product of a complex interplay and intertwining of social and ecological processes. The socio-ecological autopsy approach that is developed here traces the social and ecological chain of events that ultimately led to the outbreak and demonstrates, in particular, the need for investigative analysis to focus on the socio-ecological 'incubation' of an environmental health disaster. Drawing from both the social sciences (particularly. the sociology of disasters and organizational sociology), and from the ecological sciences (particularly disease ecology), the analysis developed here responds to the call for the application of a more transdisciplinary approach to the study of contemporary environmental health problems. Keywords: Disease outbreaks; Environmental health; Disaster incubation; Agroecosystem, new and emerging diseases; E. coli O157:H7; Canada

Thirteen different serotypes of Listeria monocytogenes can be distinguished on the basis of variation in somatic and flagellar antigens. Although the known virulence genes are present in all serotypes, greater than 90% of human cases of listeriosis are caused by serotypes 1/2a, 1/2b, and 4b and nearly all outbreaks of food-borne listeriosis have been caused by serotype 4b strains. Phylogenetic analysis of these three common clinical serotypes places them into two different lineages, with serotypes 1/2b and 4b belonging to lineage I and 1/2a belonging to lineage II. To begin examining evolution of the genome in these serotypes, DNA microarray analysis was used to identify lineage-specific and serotype-specific differences in genome content. A set of 44 strains representing serotypes 1/2a, 1/2b, and 4b was probed with a shotgun DNA microarray constructed from the serotype 1/2a strain 10403s. Clones spanning 47 different genes in 16 different contiguous segments relative to the lineage II 1/2a genome were found to be absent in all lineage I strains tested (serotype 4b and 1/2b) and an additional nine were altered exclusively in 4b strains. Southern hybridization confirmed that conserved alterations were, in all but two loci, due to absence of the segments from the genome. Genes within these contiguous segments comprise five functional categories, including genes involved in synthesis of cell surface molecules and regulation of virulence gene expression. Phylogenetic reconstruction and examination of compositional bias in the regions of difference are consistent with a model in which the ancestor of the two lineages had the 1/2 somatic serotype and the regions absent in the lineage I genome arose by loss of ancestral sequences.

Results point out that the inactivation of Salmonella serovar Enteritidis by ultrasonic waves is a phenomenon of the 'all-or-nothing' type. Data show a synergistic lethal effect between heat and ultrasound in reduced water activity media with lower water activities having the greater synergistic effect.

A total of 107 people in Fresno County, California became sick after eating at a Thai restaurant within a two-week period. The illness was traced to salt that was contaminated with the pesticide methomyl. One of the cooks lived in an apartment complex where a registered user of methomyl lived and another cook had a relative who was a registered user.

In 1999, in Toledo, Ohio, an outbreak of gastroenteritis occurred among people who had attended a Christmas dinner banquet and had eaten food prepared by a local caterer. Overall, 93 of the 137 attendees (67.9 percent) reported illness. Eight sought medical care, and one was hospitalized. Case-control studies revealed that the illness was associated with eating tossed salad (odds ratio [OR] 2.5, 95 percent confidence interval [CI] = 1.02-6.26). Eleven of 12 stool specimens that were taken from ill people tested positive for a Norwalk-like virus (NLV) but were negative for E. coli O157:H7, Salmonella, and Shigella. The primary source of the outbreak was not determined, but an infected food handler may have played a role in the transmission of the virus. The catering facility had been cited frequently for food safety and hygiene violations. None of the personnel or food handlers at this facility had been appropriately trained in safe food-handling practices, nor had the personnel at another local caterer that had prepared food items suspected of causing a multistate outbreak of NLVs. In Toledo, food service operations with trained personnel/food handlers received better inspection reports than food service operations without trained personnel and were less likely to contribute to foodborne outbreaks. Training of personnel and food handlers may be important for preventing outbreaks., Introduction In the United States, known pathogens account for an estimated 38.6 million food-related illnesses each year, of which 23 million (60 percent) are attributable to infection by Norwalk-like viruses [...]

X-ray crystal structure of Escherichia coli toxin is discussed Hemolysin E (HlyE) is a novel pore-forming toxin of E. coli and other bacteria. Three-dimensional structure determination of HlyE from E. coli K12 in its putative water-soluble secreted form is reported. So is pore formation in lipid vesicles by electron microscopy. Folding and the nature of HlyE association to form pores in membranes of cells has has been studied.

A 1997 study found that Listeria monocytogenes can cause food poisoning. Typically, Listeria can cause invasive disease even when it begins as a gastrointestinal illness. Researchers studied an outbreak of Listeria food poisoning among people attending a picnic. The infection was traced to chocolate milk produced at a plant with a defective holding tank. Samples of milk and stool from the infected patients tested positive for Listeria.

In the 10 years from 1976 to 1986, the reported number of Salmonella enteritidis infections increased six-fold in the northeastern United States. S. enteritidis infections were specifically linked to consumption of foods containing eggs. The largest hospital outbreak of S. enteritidis food poisoning ever to occur in the United States is described. In July and August 1987, 404 of the 965 patients (42 percent) at a New York City municipal hospital and nursing home became ill. Nine of the patients died from the salmonella infection. The diagnosis of salmonellosis was based upon stool cultures, which were obtained from 92 percent of the patients at the facility. Laboratory records were reviewed to estimate the rate of salmonellosis before the outbreak, the kitchen was inspected, and nine other city hospitals that received food from the same distributer were contacted about salmonellosis in their patients. It was determined that more patients on a low-sodium diet got sick than patients on other diets; S. enteritidis was then found in leftover low-sodium tuna-macaroni salad. The food poisoning was finally traced to mayonnaise prepared from raw eggs; the mayonnaise was then used in the salad. The contaminated eggs had been obtained from a farm where 69 percent of the hens' ovaries that were cultured were found to be positive for salmonella of the type including S. enteritidis. It is not known exactly how the eggs become contaminated. After this serious outbreak, the New York State Department of Health recommended that all health facilities in the state stop using raw or less-than-fully-cooked eggs in foods served to elderly patients, individuals with immune function, as well as other institutionalized persons. (Consumer Summary produced by Reliance Medical Information, Inc.)

Outbreaks of Salmonella food poisoning in the US caused by contaminated cantaloupe from Mexico occurred in April-June, 2000, April-May, 2001, and March-May, 2002. Outbreaks of Salmonella food poisoning linked to contaminated cantaloupe have occurred in the US since 1990. The CDC is working with Mexican farmers to ensure that they follow a food-safety program to prevent these outbreaks.

Byline: Sigrid Brynestad, Leif Braute, Petra Luber, Edda Bartelt Infection with Campylobacter spp. is one of the leading causes of food poisoning in Europe. In this work, a retail product to consumer model was developed in order to examine how chicken prepared in German homes exposes the consumer to Campylobacter spp. and the level of resulting illness. The model was designed to include a number of important factors in the exposure assessment and starts with the family unit where one person cooks for the whole household. The behaviour of the cook determines the exposure level of the rest of the family, but the exposure can vary between the family members. Both exposure to the bacteria from undercooking of contaminated chicken meat and from cross-contamination by hands and from the kitchen environment were addressed. The number of illnesses in Germany due to preparation and consumption of fresh and frozen chicken legs and breasts in home was estimated. The model shows that reducing the Campylobacter load on the chicken may result in a greater reduction in the incidence of human illness than reducing prevalence of contaminated products.

The article discusses the rhetoric of fear caused by contamination of spinach with E. coli which caused an outbreak of disease in September 2006. Various causes are attributed to how the contamination occurred from what could possibly have been a single patch of contaminated plants in the field which spreads throughout the processing plant during the industrial wash cycle and then dispersed throughout the nation by way of a rapid, fully integrated food distribution network.

Browning, fluorescence and pyrrole formation are determined in 4 mixtures of phosphatidylethanolamine (PE), ribose (RI), and/or lysine (lys) to analyze the contribution of lipid oxidation to food browning when lipid oxidation products are formed in the presence of other food components. The results indicate that the contribution of both carbohydrates and lipid oxidation products to food browning may be distinguished and the oxidative damage in foods can be evaluated by determining the oxidized/ethanolamine derivatives in phospholipids.

A survey is conducted to identify the presence of a single C. perfringens isolate carrying the enterotoxin gene necessary for causing food poisoning. The findings indicate that some American foods are contaminated at the time of retail purchases, with C. perfringens isolates having full potential to cause food poisoning.

Listeria monocytogenes is a ubiquitous food-borne pathogen found widely distributed in nature as well as an undesirable contaminant in a variety of fresh and processed foods. This uniquity can be atleast partly explained by the ability of the organism to grow at high osmolarity and reduced temperatures, a consequence of its ability to accumulate omo and cryoprotective compounds termed osmolytes.