Workers shuck oysters Monday at P&J Oysters in New Orleans. Federal officials plan to ban sales of raw oysters harvested from the Gulf of Mexico unless the shellfish are treated to destroy potentially deadly bacteria — a requirement that restaurants say could deprive diners of a delicacy cherished for generations.

New Orleans ? Federal officials plan to ban sales of raw oysters harvested from the Gulf of Mexico unless the shellfish are treated to destroy potentially deadly bacteria — a requirement that opponents say could deprive diners of a delicacy cherished for generations.

The plan has also raised concern among oystermen that they could be pushed out of business.

The Gulf region supplies about two-thirds of U.S. oysters, and some people in the $500 million industry argue that the anti-bacterial procedures are too costly. They insist adequate measures are already being taken to battle germs, including increased refrigeration on oyster boats and warnings posted in restaurants.

About 15 people die each year in the United States from raw oysters infected with Vibrio vulnificus, which typically is found in warm coastal waters between April and October. Most of the deaths occur among people with weak immune systems caused by health problems like liver or kidney disease, cancer, diabetes or AIDS.

“Seldom is the evidence on a food-safety problem and solution so unambiguous,” Michael Taylor, a senior adviser at the Food and Drug Administration, told a shellfish conference in Manchester, N.H., earlier this month in announcing the policy change.

Some oyster sellers say the FDA rule smacks of government meddling. The sales ban would take effect in 2011 for oysters harvested in the Gulf during warm months.

“We have one man who’s 97 years old, and he comes in here every week and gets his oyster fix, no matter what month it is,” said Mark DeFelice, head chef at Pascal’s Manale Restaurant in New Orleans. “There comes a time when we need to be responsible. Government doesn’t need to be involved in this.”

The anti-bacterial process treats oysters with a method similar to pasteurization, using mild heat, freezing temperatures, high pressure and low-dose gamma radiation.

But doing so “kills the taste, the texture,” DeFelice said. “For our local connoisseurs, people who’ve grown up eating oysters all their lives, there’s no comparison” between salty raw oysters and the treated kind.

A Gulf Coast oyster — or better still, a plate of a dozen oysters on the half-shell — is a delicacy savored for its salty, refreshing, slightly slimy taste. Some people add a drop of horseradish, lemon or hot sauce on top for extra zest.

Treated oysters are “not as bright, the texture seems different,” said Donald Link, head chef and owner of the Herbsaint Bar and Restaurant in New Orleans.

“This is an area the government shouldn’t meddle in,” Link said. “What’s next? They’re going to tell us we can’t eat our beef rare?”

Until the 1960s, raw oysters were rarely eaten in the summertime. (The old adage was never eat oysters in the months without an R in them.) But changes in harvest patterns and advances in refrigeration and post-harvest treatment have made the industry a year-round business. About three-fifths of the Gulf’s oysters are harvested during the warm months.

The FDA is promoting a ban because high-risk groups are not heeding warnings about raw oysters, and millions of other people may not know they are vulnerable.

If federal officials require post-harvest treatment, they “will be ruining an industry that has been around for centuries,” said Sal Sunseri, co-owner of P&J Oyster Co., a French Quarter oyster wholesaler.

“We’ve been doing this the same way since the 1920s,” said his brother, Al Sunseri, as shuckers in rubber gloves worked their way through piles of raw oysters destined for oyster bars and restaurants. “We’re located in the French Quarter. We’re not going to get the permits we need to do post-harvest processing. We don’t have the space for it.”

The FDA contends treating oysters would not affect the taste and would save lives.

“Oysters that undergo post-harvest processing treatment will rarely pose a problem,” Taylor said, “while those left untreated can have deadly consequences.”

The FDA cited California as the best example. In 2003, California banned untreated Gulf Coast oysters and since then “the number of deaths dropped to zero.” By comparison, between 1991 and 2001, 40 people died in California from the infection.

The rule would not affect oysters harvested outside the Gulf. Oysters are harvested up and down the West and East coasts, but the bacteria is not found in such high concentrations there.