The federal government will ban the sale of ground beef tainted with six toxic strains of E. coli bacteria that are increasingly showing up as the cause of severe illness from food. Officials have been under pressure from food safety advocates and some elected officials to do more to keep the potentially deadly bacteria out of meat, but the beef industry said the move was not needed and could force the price of ground beef to rise.

The new rule, which officials said would be announced on Tuesday, means that six relatively rare forms of E. coli will be treated the same as their notorious and more common cousin, a strain called E. coli O157:H7. That strain has caused deaths and illnesses and prompted the recall of millions of pounds of ground beef and other products. It was banned from ground beef in 1994 after an outbreak killed four children and sickened hundreds of people.

“We’re doing this to prevent illness and to save lives,” said Dr. Elisabeth Hagen, the head of food safety for the Agriculture Department, which regulates meat. “This is one of the biggest steps forward in the protection of the beef supply in some time.”

It is not illegal to sell fresh meat or poultry containing most toxic bacteria, like salmonella; they are frequently found on groceries’ meat, and thorough cooking typically kills the pathogens. But since the 1994 outbreak, which involved hamburgers served at Jack in the Box restaurants, regulators have treated E. coli in ground beef differently.

Many people eat rare or undercooked ground beef, and if it is tainted, resulting illnesses can be deadly. Toxic E. coli, in its most common O157 form, is so virulent that just a few organisms can make people violently sick. The toxic E. coli live in the digestive tracts of cows and can get on meat during slaughter. It can cause bloody diarrhea, stomach cramps and, in severe cases, kidney failure.