Salmonella foodborne illness

Each year in the United States, approximately 76 million food-borne illnesses occur, leading to 325,000 hospitalizations and over 5000 deaths.40 A number of bacterial and viral pathogens that have been discussed previously in this chapter (e.g., Salmonella, Shigella, Campylobacter, E. coli, and noroviruses) can cause food poisoning. Other bacteria that can cause foodborne illness include Staphylococcus aureus, C. perfringens, C. botu-linum, and Bacillus cereus (Table 73-5). Food poisoning should be suspected if at least two individuals present with similar symptoms after the ingestion of a common food in the prior 72 hours. 

The outbreak of Salmonella foodborne illness in Illinois in April 1985 was attributed to a tetracycline-resistant strain of Salmonella typhimurium. It evidently had no connection with feeding antibiotics in livestock. The resistant strain was of lower virulence than the average sensitive strain. 

Salmonella are a frequent cause of foodborne illness, commonly termed "food poisoning," going back long before the use of antibiotics. Salmonellosis is of unusual interest and importance to inhabitants of Chicago because of the outbreak starting in March of 1985, caused by a resistant strain of Salmonella typhimurium. 

There has been a rapid rise in foodborne illness outbreaks linked to fresh produce (Fig. 4.1). The pathogens of main concern are Salmonella and E. coli 0157 H7 although, in principle, a diverse range of pathogenic microbes can contaminate fresh produce at any point in the chain. 

There is another aspect of this entire debate relative to food safety that I have not yet addressed and, in fact, is one where biotechnology has great potential. There is consensus among food safety professionals that 98% of all real foodborne illnesses are related to bacterial food poisoning. There are numerous causes of such diseases that have proven very difficult to eliminate. These include meat and produce contamination with bacteria such as Staphylococcus, Salmonella, Eschericia coli and Clostridia botulinum. These organisms and the diseases they cause have killed more people in the United... 

Routine monitoring of important diseases by public health departments is called disease surveillance. Each state decides which diseases are to be under surveillance in that state. In most states, diagnosed cases of salmonellosis, E. coll 0157 117 and other serious infections are routinely leporied to the health department. The county reports them to the state health department, which reports them to CDC. Tens of thousands of cases of these "notifiable conditions" are reported every year. For example, nearly 35,000 cases of Salmonella infection were reported to CDC in 1998. However, most foodborne infections go undiagnosed and unreported, either because the ill person does not see a doctor, or the doctor does not make a specific diagnosis. Also, infections with some microbes are not reportable in the first place. 

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