E. coli and salmonella infections are on the rise in the United States, but other foodborne illnesses appear to have leveled off, the Centers for Disease Control and Prevention have reported.

But after falling sharply in 2003 and 2004 when the meat industry pulled together to make ground beef safer, rates of E. coli O157:H7 infections have rebounded, and many appear to be related to outbreaks in fresh produce, according to Reuters.

"As recent outbreaks have shown, too many people in the United States are getting sick each year from foodborne illnesses," CDC Director Dr. Julie Gerberding told reporters in a telephone briefing. "For instance, the outbreaks involving tomatoes, lettuce and spinach underscore the need to more effectively prevent contamination of produce.”