The new report by the Centers for Disease Control and Prevention provides yet more evidence that foodborne illness is a serious public health problem in the U.S., causing millions of illnesses, hundreds of thousands of hospitalizations and thousands of deaths each year.

It also demonstrates that, a decade after the first effort to estimate the total burden of foodborne illness, the nation remains largely ignorant of the full human and economic costs of these preventable diseases. The CDC acknowledges that the majority of illnesses are caused by unidentified organisms and that their data rely on estimates because local, state and national surveillance and reporting systems remain primitive. Most people stricken by gastrointestinal illness are never seen by a physician and if they are, only a few are tested to determine the organism that caused the illness.

The FDA Food Safety Modernization Act (S. 510), now awaiting final action in Congress, provides mechanisms to address these problems. The bill requires the Food and Drug Administration to focus on preventing rather than reacting to foodborne illness and authorizes a major expansion of surveillance and reporting systems in order to determine the agents causing illness and to improve the accuracy of estimates of the extent of illness.

The new report adds important detail to the information previously available. These include:

• Breaking the information into two separate analyses—one for major pathogens and one for “unspecified agents.”  This approach emphasizes the continuing challenge presented by lack of adequate information about the scope of and the agents responsible for foodborne illness and the great need for more intense surveillance and reporting.  It is difficult to prevent people from getting sick if you don’t know the organism causing the illness.
• Expressing the numbers of illnesses and deaths in terms of “credible intervals” or ranges, rather than simply stating a set number. The range for illnesses is from 28.7 to 71.1 million cases of illness each year. Even though the CDC used a different methodology in this report than in its 1999 study, the range shows the differences in the results are not surprisingly large.  Again improved surveillance and reporting would improve accuracy.

Finally, as CDC has reported in its annual MMWR reports on the incidence of foodborne illness in the U.S., progress in reducing foodborne illness from many of the major pathogens has stalled.  The 2009 incidence rate for Listeria was at its highest rate since 1999.  The incidence of Campylobacter infections has remained nearly the same since 2002 and little progress has been made in reducing the incidence of Salmonella illnesses since 2003. CDC identified both Salmonella and Campylobacter in its new report as among the top five pathogens causing foodborne illnesses, hospitalizations and deaths.