CLUSTER OF ESCHERICHIA-COLI O157-H7 INFECTIONS WITH THE HEMOLYTIC-UREMIC SYNDROME AND DEATH IN CALIFORNIA - A MANDATE FOR IMPROVED SURVEILLANCE

In mid-January 1993, an outbreak of Escherichia coli O157:H7 infection s associated with eating hamburger patties at a fast-food restaurant c hain (chain A) was reported in Washington State. From mid-December to mid-January, 9 cases of E coli O157:H7-associated bloody diarrhea and the hemolytic-uremic syndrome had been reported in San Diego County, C alifornia. A total of 34 persons had bloody diarrhea, the hemolytic-ur emic syndrome, or E coli O157:H7 organisms isolated from stool during the period November 15, 1992, through January 31, 1993. Organisms of E coli O157:H7 identified from 6 persons were indistinguishable from th ose of the Washington outbreak strain. Illness was associated with eat ing at chain A restaurants in San Diego (odds ratio, 13; 95% confidenc e interval, 1.7, 99) and with eating regular-sized hamburgers (odds ra tio, undefined; lower-limit 95% confidence interval, 1.3). Improved su rveillance by mandating laboratory- and physician-based reporting of c ases of E coli O157:H7 infection and the hemolytic-uremic syndrome mig ht have alerted health officials to this outbreak sooner, which could have resulted in earlier investigation and the institution of measures to prevent more cases.