Pathogens Salmonella

Safety Pathogens Salmonella Wholesomeness Welfare aspects... 

Microorganisms may have both positive and negative effects on foodstuffs. They may cause spoilage of foodstuffs and some, for example the typical food poisoning pathogens Salmonella, Staphylococcus aureus etc.), may even poison it. Moulds too may form toxic substances [7-9]. 

The most recent estimates from the CDC in the United States suggest that there are 76 million illnesses, 325,000 hospitalizations, and 5,000 deaths each year from food-borne disease. Surprisingly, the actual pathogen is identified in less than 20% of the illnesses. In other words, known pathogens account for an estimated 14 million illnesses, 60,000 hospitalizations, and 1,800 deaths. Of the known pathogens, Salmonella, Listeria,... 

Not much is known about the effect of organic acids on another important pathogen, Salmonella spp., but E. coli and Salmonella are both enteric bacteria and seem to have a similar physiology. It is, however, known that medium chain fatty acids (C6-C12, caproic, caprylic, capric, and lauric) are much more effective against Salmonella than the short-chain fatty acids (formic, acetic, propionic, and butyric). Another important finding was that the short-chain fatty acid butyrate specifically down-regulates the expression of invasion genes in Salmonella spp. at low doses. Medium-chain fatty acids and propionate also decrease the ability of Salmonella spp. to invade epithelial cells. This has been found to be in contrast to acetic acid (Van Immerseel et al., 2006). 

Pathogens Salmonella Negative Negative Negative Negative... 

Cygjer, M., Rose, D.R. and Bundle, D.R. (1991) Recognition of a cell-surface oligosaccharide of pathogenic Salmonella by an antibody Fab fragment. Science, 253, 442-445. 

In early November 2008, the Centers for Disease Control detected two clusters of food poisoning victims in 14 states that shared a common strain of pathogenic Salmonella bacteria that was ultimately traced back to PCAs Blakely plant. After FDA discovered evidence of unsanitary conditions at the plant, PCA ceased production and conducted a voluntary recall of all peanut products produced at the plant over a two-year period. The agency then discovered that the company also operated a facility in Plainview, Texas, that lacked a Texas license and had not been inspected since it opened in March 2005. When inspectors discovered peanuts contaminated with the same strain of Salmonella, that plant also ceased production. Before the outbreak was over, contaminated peanuts had sickened at least 700 people (estimates ran as high as 19,000) and killed nine. "... 

Live vectors (131,133) are another appHcation of genetic engineering. In this case, the genes from a pathogen are inserted into a vaccine vector, such as salmonella or vaccinia. In the case of salmonella, it will be possible to develop an oral vaccine. Vectors for this appHcation include salmoneUa, BCG, poHo, adenovims, and vaccinia. 

Lipopolysaccharide (LPS) endotoxins are characteristic Gram-negative outer-cell components which are produced by many cyanobacteria. Although LPS have been characterized and found to be toxic to laboratory animals after isolation from cyanobacteria, their toxicity to rodents is less potent than the endotoxins of enteric pathogens such as Salmonella Typical symptoms of animals suffering from LPS intoxication include vomiting, diarrhoea, weakness and death after hours rather than minutes. 

Some of the pathogens in Table 2, infect only humans (e.g., Vibrio cholerae. Salmonella typhi. Shigella dysenteriae, poliovirus, hepatitis A virus), whereas others, known as zoonotic, infect both humans and animals Salmonella no thypi. Shigella no dysenteriae, Campylobacter, enteropathogenic Escherichia coli such as for example the biotype 0157 H7, Cryptosporidium, etc.). The control of those that only infect humans is easier than the control of the zoonotic ones. Thus, some of them (S, typhi, S. dysenteriae, poliovirus, etc.) have practically been eradicated in many developed countries, whereas the eradication, and even the control below certain levels, of the zoonotic ones is a very difficult task. 

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