Complaints of foodborne illness in San Francisco, California, 1998

Foodborne diseases are an important public problem affecting millions of Am ericans each year and resulting in substantial morbidity and mortality. Man y foodborne infections occur in outbreak settings. Outbreaks are often dete cted by complaints from the public to health authorities. This report revie ws complaints received by the San Francisco Department of Public Health inv olving suspected foodborne illness in 1998. Although such foodborne complai nts are commonly received by health officials, we provide the first review of population-based data describing such complaints. We use a broad definit ion of a foodborne disease outbreak. We judged a complaint to be a "likely foodborne disease outbreak" if it involved more than one person and more th an one family; no other common meals were shared recently by ill persons; d iarrhea, vomiting, or both was reported; and the incubation period was more than one hour. In 1998, 326 complaints of foodborne illness, involving a t otal of 599 ill people, were received by the Communicable Disease Control U nit in San Francisco. The complaints involved from I to 36 ill persons, wit h 61% involving one ill person and 25% involving two ill persons. Of the 12 6 reports involving illness in more than one person, 77 (61%) were judged t o be likely foodborne disease outbreaks. Three of these 77 outbreaks had be en investigated prior to our review. This project confirms that more foodbo rne disease outbreaks occur than are reported to state and national outbrea k surveillance systems. Our review of the San Francisco system highlights o pportunities for gleaning valuable information from the foodborne disease c omplaint systems in place in most jurisdictions.