Is it safe to eat sushi, the Japanese raw fish specialty?

People in the at-risk groups should not eat raw or undercooked fish or shellfish. People with liver disorders or weakened immune systems are especially at risk for getting sick. Foods made with raw fish are more likely to contain parasites or Vibrio species than foods made from cooked fish. Always cook finfish until its muscle is opaque and flaky.

Why are shellfish and salads especially "friendly" to viruses?

Shellfish are especially "friendly" to viruses because shellfish pump water through their bodies and thus, concentrate food and contaminants, such as viruses, from the water. Once the virus is on or in the shellfish - a live host - it may persist for a longer time than if it were suspended in the water. Some shellfish are eaten raw or lightly cooked, which increases the risk of foodborne illness.Produce used for salads, lettuce, spinach, etc., grow low to the ground where they are more likely to come in contact with contaminated, organic fertilizers, such as manure. Also, sometimes produce is irrigated with contaminated waters or picked by farm workers with poor hygiene practices. The complex, multi-layered surfaces of salad produce are more difficult to clean after picking than, for example, the surface of an apple or potato. Finally, because salads are usually eaten raw, there is no heating step that would inactivate the viruses.

How can you figure out if the fish is fresh?

• The fish's eyes should be clear and bulge a little. Only a few fish, such as walleye, have naturally cloudy eyes.
• Whole fish and fillets should have firm and shiny flesh. Dull flesh may mean the fish is old.
• Fresh whole fish also should have bright red gills free from slime.
• If the flesh doesn't spring back when pressed, the fish isn't fresh.
• There should be no darkening around the edges of the fish or brown or yellowish discoloration. The fish should smell fresh and mild, not fishy or ammonia-like.

How can you spot a safe seafood seller?

Anyone who's ever smelled rotting seafood at the fish counter has a pretty good idea of what a poorly run seafood market smells like. But the absence of any strong odor doesn't necessarily mean that the seller is practicing safe food handling techniques.

Based on FDA's Food Code, here are some other points to consider:

• Employees should be in clean clothing but no outerwear and wearing hair coverings.
• They shouldn't be smoking, eating, or playing with their hair.
• They shouldn't be sick or have any open wounds.
• Employees should be wearing disposable gloves when handling food and change gloves after doing nonfood tasks and after handling any raw seafood.
• Fish should be displayed on a thick bed of fresh, not melting ice, preferably in a case or under some type of cover.
• Fish should be arranged with the bellies down so that the melting ice drains away from the fish, thus reducing the chances of spoilage.
  

What's your general impression of the facility? Does it look clean? Smell clean? Is it free of flies and bugs? A well-maintained facility can indicate that the vendor is following good sanitation practices. Is the seafood employee knowledgeable about different types of seafood? Can he or she tell you how old the products are and explain why their seafood is fresh? If they can't, you should take your business elsewhere.

How can I avoid seafood economic fraud?

To get the best value for your money when buying seafood, it's important to know what you're buying. Be wary of unusual bargains--some seafood is seasonal. If there is a considerable difference between the price of a fresh product and what you are accustomed to paying, it could be that it is from the last season's frozen inventory. Buy from a reputable dealer. And if the fish you choose looks or smells different from what you expect, discuss it with the fish market manager. Look for firm, shiny flesh that bounces back when touched. If the head is on, the eyes should be clear and bulge, and the gills should be bright red. The fish should not smell "fishy"--it should smell like a fresh ocean breeze. It's easy to miss the telltale signs of species substitution. Sometimes, taste or consistency is the only way to detect it. If you feel you have purchased something different from what was represented, tell your fish market manager.

Here's how to distinguish some common species:

• Haddock has a dark lateral line along the skin surface. Skinless cod fillets have a distinctive white papery membrane along the belly and a white line of fat along the lateral line of the fillet.
• Shark and swordfish look alike, but shark has a dark streak of flesh in the center and rough skin along the edge.
• Red snapper comes only from the southern Atlantic Ocean and the Gulf of Mexico (ask your retailer where the snapper originated).
• Orange roughy comes only from Australia or New Zealand and always arrives frozen. It may be sold thawed, but it must be labeled as previously frozen.
• Scrod is not a type of fish. The term originated in the Boston area to describe the catch of the day. It is a fish under two and a half pounds that is either cod, haddock or pollock. Such fish should be labeled in the market or listed in a restaurant as "scrod cod," "scrod haddock," or "scrod pollock."

How can you select safe seafood?

• Buy only from reputable sources.
• Be wary, for example, of vendors selling fish out of the back of their pick-up trucks.
• Buy only fresh seafood that is refrigerated or properly iced.
• Don't buy cooked seafood, such as shrimp, crabs or smoked fish, if displayed in the same case as raw fish. Cross-contamination can occur.
• Don't buy frozen seafood if the packages are open, torn or crushed on the edges. Avoid packages that are above the frost line in the store's freezer.
• If the package cover is transparent, look for signs of frost or ice crystals. This could mean that the fish has either been stored for a long time or thawed and refrozen.
• Put seafood on ice, in the refrigerator or in the freezer, immediately after buying it.
• Recreational fishers who plan to eat their catch should follow state and local government advisories about fishing areas and eating fish from certain areas.