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Fresh spinach and products containing fresh spinach should remain off U.S. plates, following a multistate E. coli outbreak linked to one death and scores of illnesses.

Here are 14 questions and answers for consumers about the outbreak and spinach warning.

Q. How long will the FDA’s warning on fresh spinach last?

A. Until further notice.

“That’s a particularly difficult question to answer,” CDC spokeswoman Christine Pearson tells WebMD.

“Typically, with food-borne outbreaks, it really is a process of just trying to get all the information you can and so it may take a while to get to that point,” Pearson says.

“The ban on spinach will last until FDA releases the alert,” Richard Linton, PhD, tells WebMD in an email. “This will occur once FDA is comfortable that they have isolated the source of potentially contaminated product. This will likely take days to weeks.”

Linton is a professor of food safety and director of the Center for Food Safety Engineering at Purdue University.

Q. What is E. coli?

A. E. coli is a bacterium. There are hundreds of strains of E. coli bacteria; the strain involved in the current outbreak is E. coli 0157:H7.

Q. Is this strain of E. coli more dangerous than other strains?

A. Yes.

“E coli 0157 is a particularly dangerous type of E. coli because it can lead to hemolytic uremic syndrome,” says Pearson. “So it can be more severe for people.”

Q. What is hemolytic uremic syndrome?

A. Hemolytic uremic syndrome is a life-threatening complication of E. coli infection affecting the kidneys.

It’s usually treated in intensive care and often requires blood transfusions and kidney dialysis. Young children and the elderly are at particular risk for the complication.

Even with intensive care treatment, the death rate for hemolytic uremic syndrome is 3% to 5%, according to the CDC.

Q. Do most infected people develop hemolytic uremic syndrome?

A. No.

“That’s definitely not the case,” Pearson says. An estimated 2% to 7% of infections lead to this complication, according to the CDC web site.

Q. What are the symptoms of E. coli infection?

A. “Basically, the common symptoms for E. coli are severe bloody diarrhea, and cramping. Sometimes it isn’t necessarily bloody,” Pearson says.

“Anybody who does develop diarrhea after consuming fresh spinach should see their doctor and also ask that [the doctor] take a specimen for testing,” she adds.

Q. How long does it usually take before symptoms start?

A. “Twelve to 36 hours, normally. Up to a week in some cases,” Linton says.

Q. For people who used to eat fresh spinach often, what are some alternatives?

A. If you’re looking for fresh greens, try lettuces such as radicchio, escarole, and romaine. Arugula, collard greens, mustard greens, and kale are other options, say Amy Jamieson-Petanic, RD, and Lola O’Rourke, RD, spokeswomen for the American Dietetic Association.

The spinach ban could be an opportunity to experiment with other greens, says O’Rourke, who is based in Seattle.

“We don’t want people to stop eating fresh fruits and vegetables, because they’re so important for good health,” says Jamieson-Petanic. “They’re wonderful sources of vitamins and minerals.”

Jamieson-Petanic manages the Fairview Hospital Wellness Center in Rocky River, Ohio, near Cleveland.

Q. Can you trust fresh spinach that’s locally grown, such as spinach from farmers markets?

A. Until further notice, the FDA advises people not to eat fresh spinach from any source, including supermarkets, restaurants, and farmers markets.

Q. Should we worry about frozen spinach, canned spinach, or spinach baby food?

A. No.

At this time, the FDA has no evidence frozen spinach, canned spinach, or spinach in premade meals manufactured by food companies are affected. These products are safe to eat, according to the FDA.

“Frozen spinach is normally ‘blanched’ with hot water or steam prior to being frozen, which should be effective for destroying E. coli,” Linton explains.

“The thermal process given for all low-acid foods, including baby food and canned spinach, is done at 230 [degrees Fahrenheit] or higher, where E. coli will be destroyed. E. coli is destroyed at 160-165 [degrees Fahrenheit,” Linton says.

Q. Can people cook fresh spinach or salad blends containing fresh spinach?

A. The FDA currently recommends that the public not consume fresh (uncooked) spinach or salad blends containing fresh spinach. However, E. coli O157:H7 in spinach can be killed by cooking at 160 degrees Fahrenheit for 15 seconds.

If consumers choose to cook fresh spinach, they should follow these cooking instructions and also take steps to avoid cross-contamination between the fresh spinach and other food or food- contact surfaces. They should wash hands, utensils, and surfaces with hot, soapy water before and after handling fresh spinach.

Q. Does the spinach warning apply only to bagged fresh spinach?

A. No.

Fresh spinach in this warning includes bagged spinach, spinach in plastic “clamshell” containers”, and loose spinach purchased from retailers, says the FDA.

Q. Does the spinach warning apply to organic spinach as well as conventionally grown spinach?

A. Yes.

The FDA’s warning applies to all fresh spinach, regardless of the growing method.

Q. What does the FDA recommend doing with fresh spinach or products containing fresh spinach that consumers may already have?

A. The FDA recommends that the product be thrown away.

By Miranda Hitti, reviewed by Louise Chang, MD

SOURCES: FDA, “Statement on Foodborne E. coli 0157:H7 Outbreak in Spinach -- Update: Wednesday, Sept. 20, 2006.” Christine Pearson, spokeswoman, CDC. Richard Linton, PhD, professor of food science and director, Center for Food Safety Engineering, Purdue University. WebMD Medical News: “E. coli Outbreak: Questions & Answers.” CDC: “Escherichia coli O157:H7”. Amy Jamieson-Petanic, RD, ADA spokeswoman; manager, Fairview Hospital Wellness Center. Lola O’Rourke, RDA, ADA spokeswoman. FDA: "Nationwide E. Coli 0157:h7 Outbreak: Questions & Answers."