Fish and seafood are a main source of animal protein in the diet. Because of their
health advantages over red meats, the consumption of fish and seafood has
increased. Catches can be gathered from seas, rivers and lakes whose water can
range from pristine to contaminated. Often contamination is from human and
animal sources; thus, fish and seafood can be involved in the transmission of
pathogenic microorganisms and toxins. Geographical region, season, and, for fish,
whether they are pelagic (surface to mid-water) or demersal (bottom) feeders will
influence the numbers and types of microorganisms present on freshly caught
seafood.