rare or not reported due to lack of severity of symptoms (see Table 4-9) (IOM, 1991). The two principle pathogens of concern are Salmonella spp. and Listeria monocytogenes.

Salmonella is a bacterium of widespread occurrence in animals, especially in poultry and swine. Environmental sources of the organism include water, soil, insects, factory and kitchen surfaces, animal feces, raw meats and poultry, and raw seafoods. S. typhi and the paratyphoid bacteria normally cause septicemia and produce typhoid or typhoid-like fever in humans. Other forms of salmonellosis generally produce milder symptoms (Source: http://www.cfsan.fda.gov/~mow/chap1.html).

Listeria monocyotogenes is a bacterium that can cause a serious infection in humans called listeriosis. Foodborne illness caused by L. monocytogenes in pregnant women can result in miscarriage, fetal death, and severe illness or death of a newborn infant. Others at risk for severe illness or death are older adults and those with weakened immune systems. L. monocytogenes can grow at refrigerator temperatures and is found in ready-to-eat foods (Source: http://www.cfsan.fda.gov/~dms/adlister.html 2003).

Federal regulation prohibits the sale of any raw or cooked seafood products contaminated with any Salmonella, or cooked, ready-to-eat seafood products contaminated with any L. monocytogenes (CFSAN, 2001) (see Appendix Table B-4). The zero tolerance policy for Salmonella on any seafood product is historically based on concerns for unsanitary practices that contaminated a food after harvest. The presence of any Salmonella on seafood from freshwater or saltwater harvests is considered an adulterant. Inland aquacultural production can expose farmed seafood to Salmonella from other animal sources including neighboring wildlife. Koonse et al. (2005) evaluated both product and environments (source water and grow-out pond water) from shrimp aquaculture across six countries, and found a significant association between the concentrations of Salmonella and both fecal coliforms and E. coli. Nevertheless, the occurrence of seafoodborne salmonellosis is rare. Reported cases are usually the result of cross-contamination or unsanitary handling practices (Koonse et al., 2005). Proper sanitation that includes adherence to Hazard Analysis and Critical Control Point (HACCP) regulatory requirements for daily sanitary monitoring and records plus cooking of seafood appear to be adequately controlling Salmonella in seafood.

Likewise, proper sanitary practices and cooking temperature remain the primary control points to prevent potential illnesses due to contamination from particular types and amounts of L. monocytogenes (Lm) that have been found on certain seafood products (Gombas et al., 2003). The most likely vehicle of transmission is previously cooked and ready-to-eat (RTE) seafood products with prolonged refrigerated storage that could al-



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