Q. Do most infected people develop hemolytic uremic syndrome?
"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, 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-Petonic, 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-Petonic. "They're wonderful sources of vitamins and minerals."
Jamieson-Petonic 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.
"There's no evidence to indicate that spinach that is obtained from a local farmers market outside of the areas that have been implicated with the outbreak -- the three counties that we discussed [California's Monterey, San Benito, and Santa Clara counties] -- is in any way implicated in this outbreak," Acheson tells WebMD.
"The difficulty with putting out a nationwide consumer message is obviously the need for clarity," he says.
"If an individual ... knows exactly where the spinach was grown, and they know it wasn't implicated in an area of concern as part of this outbreak, then obviously it would be safe to consume," Acheson says.
The FDA is working on a process to allow spinach not grown in the three California counties to be allowed back on store shelves, but that plan isn't in place yet.