Janice Okun of The Buffalo News says: "So now it’s lettuce that can make you sick. Who knew?"

Most people have been aware that undercooked ground beef can be an enemy. There is a chance that the meat could harbor deadly E. coli bacteria. But one of the more sobering items in the news recently concerned some 26 people in the Midwest who became deathly ill, most likely from eating bagged lettuce, marked prewashed, that had been picked and packaged in California.

Leafy greens (including spinach) have always been suspected of harboring E. coli since they grow in soil that has been exposed to feces-infested food and water.

In addition, because they are usually served raw, the standard heat treatment to kill the bacteria is not utilized.

Millions of Americans eat prewashed bagged salads safely. But the Food and Drug Administration says there have been at least 19 food-borne illness outbreaks linked to leafy greens since 1995. A total of 425 people have become seriously ill and two have died.

Until a solution is found, experts recommend washing pre-washed lettuces under cold water and refrigerate promptly, and only for a limited time: Don’t keep iceberg lettuce in the fridge for one to two weeks, leafy lettuce for more than three to seven days.