While the data showed a promising five-year decline of E. coli O157:H7 and Shigella infections since 2007, infection rates stagnated or slightly grew for a number of other notable bacteria, including Salmonella, Campylobacter and Listeria.
According to the data, Salmonella, Campylobacter and Listeria continue to infect numbers well beyond goals set by the U.S. government for 2010:
For every 100,000 people, 16.5 fell ill with Salmonella in 2011 and 17.5 the year before, despite a goal to reduce that number to 6.8 by then. Similarly, Campylobacter infected 14.3 in 2011 (surpassing the 12.3-person goal), and 0.28 were sickened by Listeria (just above the 2010 goal of 0.24). At the same time, however, E. coli O157 rates fell to 0.98, just below its goal of 1.0.
"If you look at the trend for O157, you can make a fairly coherent argument that listing that bug as an adulterant and having zero tolerance for it has driven its numbers down," Marler said. "I think that industry and the public would be well-served if Campylobacter and Salmonella -- especially antibiotic-resistant strains -- were considered adulterants and were no longer tolerated in the food supply."
And while O157's number have dropped by more than 250 percent since 1996, other toxin-producing E. coli strains have seen a dramatic rise in the last two years. In 2011, infection rates of these strains -- collectively referred to as 'non-O157 E. coli' -- rose above O157's for the first time.
As of June 4, 2012, the U.S. Department of Agriculture now considers six of the most prevalent non-O157 E. coli strains adulterants, ranking them in line with O157. Health officials hope the new designation will help drive those infection rates back the opposite direction.
The CDC's annual data come from FoodNet, a network that coordinates data from public health laboratories across 10 states. The regions represented include 47 million people, 15 percent of the U.S. population.