P1: OTA c11 JWBS012/Heredia November 3, 2008 22:1 Printer Name: Yet to Come CHAPTER 11 FOOD SAFETY ISSUES AND THE MICROBIOLOGY OF FISH AND SHELLFISH LUCIO GALAVIZ-SILVA, GRACIA GOM ´ EZ-ANDURO, ZINNIA J. MOLINA-GARZA and FELIPE ASCENCIO-VALLE 11.1 INTRODUCTION Fish and fishery products are at the forefront of food safety and quality improvement because they are among the most internationally traded food commodities. Of the products used for human consumption, fresh fish showed significant growth from 1990 to 2005 (FAO, 2007). Approximately 45% of the fish used for human consump- tion is sold fresh, 30% frozen, 14% canned, and 12% cured (Gram et al., 2002; Huss et al., 2003). Seafood includes cephalopods (octopus, squid), freshwater and salt- water fish (including finfish), and shellfish. Shellfish include the bivalve molluskan shellfish (oysters, cockles, clams, and mussels), gastropods (periwinkles, sea snails), and crustaceans (crab, lobster, and shrimp). Seafood is an important part of a healthy diet. In some countries it is the main source of animal protein. Furthermore, it has become a healthy alternative to other animal protein (e.g., beef), because it contains low fat and beneficial omega-3 polyunsaturated fatty acids. Au: Please add to ref. list Huss, 1977. Despite its benefits, seafood consumption can cause allergic reactions, infection, or intoxication (Huss, 1977). In this chapter we focus on infection and intoxica- tion. Infection and intoxication from seafood consumption are commonly caused by ingestion of the microorganisms that live in seafood tissue. Foodborne illnesses from seafood are more common in countries with high seafood consumption or traditions of eating seafood raw. Twenty percent of foodborne ill- nesses in Australia and more than 70% in Japan were related to seafood consumption in 2003 (Butt et al., 2004). Most of the infectious outbreaks from seafood appear to be due to shellfish rather than to finfish. A study from New York attributed 64% of Microbiologically Safe Foods, Edited by Norma Heredia, Irene Wesley, and Santos Garc´ ıa Copyright C  2009 John Wiley & Sons, Inc. 227