Outbreaks of foodborne illness reported in 2008 declined by about 10% when compared with the annual average for 2003-2007, according to the latest annual report from the U.S. Centers for Disease Control and Prevention (CDC) on surveillance of foodborne disease outbreaks. The average number of outbreaks reported for 2003-2007 was 1,151, compared with 1,034 for 2008.
But Robert Buchanan, PhD, director of the University of Maryland’s Center for Food Safety and Security Systems, cautions that most foodborne disease is associated with sporadic cases, not outbreak clusters. “This isn’t like the report card that they issued earlier in the year, based on data over a period of five to 10 years. That one included both outbreak and sporadic cases.”
The agency and its public health partners also appear to be doing a better job of tracing outbreaks. The report indicates that health departments were able to identify the food that made people sick in 481 cases, and the specific disease agent in 479 cases—which comes out to about 46%. In a 2006 Scripps Howard News Service investigation, which looked at nearly 6,400 outbreaks between 2000 and 2004, only about 36% of investigations yielded a cause of illness.
“That’s still less than half, but it’s getting better,” said Dr. Buchanan. “I think this is due to a combination of enhanced surveillance and investigation by the CDC, U.S. Food and Drug Administration, and Food Safety and Inspection Service, plus the states, along with new technology such as fingerprinting and the new requirements for traceability in the system.”
Norovirus and Salmonella ranked first and second as the most common pathogens, accounting for 49% and 23% of outbreaks, respectively. The re-emergence of Salmonella indicates the truth of observations made in an earlier report by the CDC on the overall burden of foodborne disease, Dr. Buchanan said: “Salmonella is one pathogen we haven’t made a substantial amount of progress in controlling. We’ve seen a bit of a switch in the vehicles for the organisms. For example, while there are a large number outbreaks associated with poultry, beef, and fin fish—which has been pretty typical for the past decade—the commodities that may not have the most outbreaks but have the most related illnesses are fruits and nuts, vine-stalk vegetables, and, to a lesser extent, beef. We’re seeing a refocusing of concerns about Salmonella into newer commodities, which has been developing over the last 10 years.”