11 Bacteria Cases Prompt L.A. County Warning : Health: More than half the cases are in Antelope, San Fernando and Simi valleys. Ground beef is called a ‘risk food’ that always should be well cooked.

The number of illnesses caused by E. coli--a potentially deadly bacteria commonly found on undercooked hamburger meat--is on the rise, with 11 reported in Los Angeles County, all since April, contrasted with just nine in all of 1993.

More than half of the cases, none of them fatal, have been found in the San Fernando, Simi and Antelope valleys. So far, health officials have not found a common origin of tainted food.

Two of the victims were siblings, ages 2 and 3, from Lancaster. The most severe case was a 69-year-old man from Canoga Park who became ill on June 22 and was hospitalized for a week. Eight of the 11 cases required at least one day’s hospitalization.

Health officials say the illness--which killed three children and sickened more than 600 other people in Washington state last year--is easily prevented by cooking ground meat until it is well done.

Although the county does not keep an official list of “risk” foods, Dr. Shirley Fannin, director of disease control for Los Angeles County, said Wednesday the recent outbreak and growing knowledge about the health dangers of undercooked hamburger have led health authorities to put ground beef in the same classification as chicken, unpasteurized milk and pork, meaning that if not handled right it can be harmful, leading even to death.

“Just cook your meat so that it’s not pink in the middle,” Fannin said. “If you order a hamburger at a restaurant and it’s pink in the middle, send it back.”

Fannin said the bacteria, which was first discovered in 1982, is most commonly found in raw or undercooked ground meat, primarily hamburgers. She said cooking the meat until it is brown throughout kills any bacteria.

Because health officials cannot trace the Los Angeles County infections to a common source, they are not sure if this is an outbreak or coincidence.

“We’re just not sure because the cases are not clustered in one place and not related to a single source like a restaurant,” said Fannin. “So we are just telling people that if they don’t thoroughly cook their food, then they are taking a risk of getting an infection.”

A state health official suggested the increase this year may simply reflect increased testing for E. coli by doctors in the wake of the Washington deaths.

“E. coli is a lot more prevalent than people might imagine, but it is just not routinely looked for by doctors,” said Dr. Ben Werner, a medical epidemiologist with the state Department of Health Services. “The fact that the (Los Angeles) cases are scattered in time and place would indicate that there is not an outbreak.”

Early last year, the outbreak of illnesses in Washington state was traced to undercooked hamburgers at Jack-in-the-Box restaurants. The outbreak prodded the U. S. Department of Agriculture to require safe handling labels on packages of raw and partly cooked ground beef, sausage and poultry, as of this July 6.

The labels inform consumers that the product might contain bacteria that could cause illness if the meat is not cooked completely, kept refrigerated or otherwise properly handled.

The main problem associated with hamburger is that the bacteria, if it is in or on the meat, has a huge surface to contaminate, as opposed, say, to steak. Health authorities say they believe it is still all right to eat rare steak because the outside surfaces of the meat, where the problem develops, all get cooked.

But, even with steak, the California Beef Council, which has joined health authorities in advocating better preparation of meat, warns that marinade used to flavor meat should be boiled at least a minute before being eaten and that platters used for raw roasts and steaks should be washed with hot water and soap before the cooked meat is placed back on them.

The U. S. Food and Drug Administration also increased its recommended cooking temperature for ground meat from 140 degrees to 155 degrees for at least 15 seconds.

The county’s warning comes on the heels of a strongly worded statement released in Washington last week by the American Gastroenterological Assn. Foundation calling federal meat inspection systems “insufficient in themselves to identify microbial contamination such as” E. coli.

Dr. Martin Brotman, a San Francisco physician and chairman of the foundation, said infections from the E. coli strain “pose a clear and present danger to our public health.” The statements were said to be a consensus formulated by a panel composed of health professionals in gastroenterology, epidemiology, public health, microbiology, food science, food service, industry and consumer affairs.

All 11 cases in Los Angeles County this year involved hamburgers, both cooked at home and at restaurants. The first case was reported April 9, and the most recent last week. Five of the cases were reported in June.

Seven of the 11 cases involved children, and the victims ranged in age from 2 to 69 years old. The individuals live in Lancaster, Simi Valley, Westlake Village, Woodland Hills, Canoga Park, North Hollywood, Norwalk, Beverly Hills, Santa Monica and Rancho Palos Verdes.

Children under 2 and adults over 65 are the most vulnerable to the disease, which in severe cases can cause kidney failure and death. Symptoms include abdominal cramps, vomiting and bloody diarrhea, which may appear as early as 12 hours after ingestion and as late as 10 days.

Health officials said the infection can be treated with antibiotics if diagnosed in time and preventing it is largely a matter of increasing public awareness about its cause.

“Everybody knows that you shouldn’t eat rare or undercooked chicken because of the danger of salmonella bacteria, but people don’t seem to know about hamburgers,” said Werner, the state epidemiologist. “Well, in my opinion, the era of eating rare hamburgers should be behind us.”

Times staff writer Douglas P. Shuit contributed to this story.