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diseases with a long incubation period, such as chronic heavy- 

 metal poisoning or cancer potentially associated with long-term 

 consumption of fish from polluted water, would not be detected by 

 CDC's National Foodborne Disease Outbreak Surveillance System. 



Although our current Foodborne Outbreak Surveillance System 

 is critical to our understanding of foodborne disease and its 

 control, the information focuses only on outbreaks of diseases. 

 However, most foodborne disease, including diseases associated 

 with seafood, occurs as sporadic, or individual cases, rather 

 than as part of recognized outbreaks. The characteristics of the 

 sporadic cases can be very different. These differences have 

 important implications for the control of illness in humans. For 

 example, persons with liver disease who eat raw oysters can get a 

 devastating, frequently fatal infection of Vibrio vulnificus, but 

 no outbreaks caused by this bacterium have been reported. Data 

 on such sporadic or individual cases, in addition to those from 

 reported outbreaks, would be needed to fully characterize the 

 risk associated with seafood products. 



In 1989, in collaboration with the National Marine Fisheries 

 Service, CDC analyzed data reported by the states on foodborne 

 disease from 1973 through 1987. Recently, in collaboration with 

 FDA, CDC analyzed foodborne disease outbreak data available for 

 1988-1991. 



Keeping in mind the limitations of these data, we can 

 examine the trends in foodborne diseases using this outbreak 

 surveillance information for the period 1973 through 1991. 

 During these 19 years, 4591 outbreaks of disease in which the 

 causative food was known were reported to the CDC foodborne 

 outbreak surveillance system. These outbreaks affected 202,850 

 persons. Seafood accounted for 20% of the outbreaks, compared 

 with 8% for beef, 7% for poultry, and 1% for eggs. However, the 

 number of cases of illness in these outbreaks is more important 

 than the number of outbreaks themselves in determining the public 

 health impact of diseases associated with a specific food 

 vehicle. Because most outbreaks attributed to seafoods involved 

 fewer persons than those due to other foods, seafood accounted 

 for only 5% of all reported foodborne outbreak-associated cases, 

 compared to 10% for poultry, 9% for beef, and 2% for eggs. 



Despite our achievements in outbreak investigations, 

 continuing hazards in our food supply tell us we must do better. 

 We have identified activities that will lead to better control of 

 foodborne disease. These activities include strengthened 

 surveillance for emerging human pathogens, rapid and effective 

 reaction to foodborne disease, and proactive foodborne disease 

 prevention programs. I will discuss each of these in more 

 detail. 



Rapid and effective reaction to foodborne disease requires a 

 nationwide system in which public health laboratories in all 

 states identify potential foodborne pathogens, electronically 

 transmit the information to CDC for cluster analysis and 

 interpretation, and rapidly relay appropriate microbial isolates 

 to CDC for molecular epidemiologic studies. CDC has developed a 

 computer-based data management and reporting system (the Public 

 Health Laboratory Information System) and is in the process of 

 installing this system in all public health laboratories. We are 

 also developing software modules for the foodborne pathogens of 

 interest. CDC is expanding and improving pathogen subtyping 

 systems which yield CDC important information regarding strain 

 differences in foodborne pathogens. Such systems will help 

 refine CDC's ability to identify case clusters and unusual 

 events. Laboratory and human resource needs in state public 

 health laboratories must also be addressed. 



Proactive foodborne disease prevention programs for 

 recognized hazards require quantitative risk assessment and 



