ENC Regional News
12:39 pm
Fri June 4, 2010

Workshop seeks to reduce risk of illness from consuming raw shellfish

Workshop seeks to reduce risk of illness from consuming raw shellfish

New Bern, NC – INTRO - A workshop in Morehead City next week geared toward shellfish harvesters, dealers and retailers aims to reduce the risk of illness to consumers from eating raw shellfish tainted by naturally occurring bacteria. George Olsen has more.

First things first if you take that oyster shell, pop it open, smother its meat in batter and then throw it in the deep fryer, you're good to go. Same thing if you leave them in the shell and steam them thoroughly on the grill. But for those who like a raw oyster or clam experience, there's a risk involved with that tasty treat especially in the Southern states.

"It takes several thousand cells to cause illness, so a low level of ingestion isn't going to be a problem at all. When it becomes a problem is when waters are over 80 degrees fahrenheit. The numbers tend to increase, and even then it's usually not a problem with shellfish coming right out of the water, but once they come out of the water if they're not properly handled, if they're allowed to warm up the bacteria can continue to multiply and that's when we start to see illnesses."

Bob Rheault, the executive director of the East Coast Shellfish Growers Association and the man who'll lead the workshop Wednesday. The "several thousand cells" he's referring to come from two naturally occurring bacteria in shellfish both which can cause gastroenteritis and its symptoms including nausea and diarrhea but most notably vibrio fulnificous which doesn't regularly cause illness but when it does can lead to the most serious of consequences.

"It's a very, very uncommon illness and it only affects people who are immune compromised those with liver disease or on an immunosuppressant drug, so there's about 60 cases a year. Half of those are related to wound infections, the other half are related to the consumption of shell fish so about 30 cases a year which means the typical doctor hasn't seen a case of vibrio fulnificous, but the nastiest thing about this bug is it causes 50% of the people who come down with the illness find it fatal, so it's a huge issue in very warm waters."

Rheault cites some alarming numbers on what happens to shellfish after harvest that the number of bacteria increases a hundred-fold between harvest and consumption and the bacteria can double in under an hour in 90-degree temperatures very common down South.

"First of all there's the starting dose how many bacteria were in the oyster when it was harvested. As I said there has to be tens of thousands of bacteria in an oyster to cause illness so if the waters were very warm when the oyster or clam was harvested, they might be starting out with several thousand bacteria which would not be a problem but if the shellfish is not handled properly, in the matter of a few hours, you double it once, you double it twice and suddenly you have a potential problem."

For the harvesters, dealers and retailers, the message actually is pretty simple keep your shellfish cool. The bacteria will not grow in temperatures below 45 degrees. There are already rules in place at the first link in the supply chain to deliver a safe product to consumers.

"The harvester, we've instituted regulations in most Southern states that say you can't be out there more than five hours so you have to get them to refrigeration within five hours of harvest and that cuts down on the amount of time the shellfish is sitting on the deck, and we've instituted regulations saying they must be under shade."

The Shellfish Growers Association advocates the use of ice on harvest boats and for dealers to take the product straight to refrigeration units. They also want truckers to know the best spots in their truck to load shellfish so that when other product is added or removed the shellfish is less likely to warm up. But while Wednesday's workshop is geared toward harvesters, dealers and retailers, there is one last line of defense.

"We'd like the consumer to go shopping with a cooler and ice pack. If they purchase shellfish at the seafood market they can't delay putting it into the refrigerator at home, they've got a responsibility to get it home quickly, to keep it cool on the drive home and treat the food properly. It's good common sense but you'd be shocked at how many people don't understand the risk."

Bob Rheault is the executive director of the East Coast Shellfish Growers Association. He'll lead a workshop this Wednesday at the Center for Marine Sciences and Technology in Morehead City.