Food Poisoning Health Center

Spinach & E. coli: Questions & Answers

Sept. 22, 2006 -- Fresh spinach and products containing fresh spinach should remain off U.S. plates, following a multistate E. coli outbreak linked to at least one death and scores of illnesses.

The FDA's investigation is centering on spinach grown in three California counties -- Monterey, San Benito, and Santa Clara -- the FDA's David Acheson, MD, told reporters in a teleconference.

Acheson is the chief medical officer in the FDA's Center for Food Safety and Applied Nutrition.

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?

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?

"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.