Corrected: Multistate Outbreak of E.
coli 0157 Infections, November-December 2006
This message is being sent to correct the information within
CDC Health Update (CDCHAN-00255-06-12-14-UPD-N).
As of 12:00 PM (EST)
Wednesday, December 13, 2006, 71 persons with illness associated with the Taco
Bell restaurant E. coli 0157 outbreak have been reported to CDC from 5
states: New Jersey (33), New York (22), Pennsylvania (13), Delaware (2), and
South Carolina (1). States with Taco Bell restaurants where persons confirmed
to have the outbreak strain have eaten are New Jersey, New York, Pennsylvania,
and Delaware. (The patient from South Carolina ate at a Taco Bell restaurant in
Pennsylvania). Other cases of illness are under investigation by state public
health officials. Among these 71 ill persons, 53 (75%) were hospitalized
and 8 (11%) developed a type of kidney failure called hemolytic-uremic syndrome
(HUS). Illness onset dates have ranged from November 20 to December 6.
The number of cases peaked in the last week of November. No
illnesses were reported with onset within the past week, so the outbreak is
over.
Cases
in 48 of the 71 patients are confirmed, meaning that the patients’ E. coli O157 strains have the outbreak “DNA
fingerprint.” E. coli O157 strains are
routinely “DNA fingerprinted” at public health laboratories in all states as
part of PulseNet (the network of public health laboratories that sub-type
bacteria). E. coli O157 strains
from other cases are being tested by PulseNet. As a result of testing by
PulseNet, cases with the outbreak strain “fingerprint” pattern are being
re-classified as confirmed cases, and cases with an unrelated “fingerprint”
pattern are being dropped from the outbreak case count.
CDC is working with
state and local health officials, the Food and Drug Administration (FDA), the
Department of Agriculture (USDA), and the restaurant chain to determine what
food caused the outbreak. Public health investigators have identified a
few ingredients that were consumed more often by ill persons than well persons
and were statistically linked with illness: lettuce, cheddar cheese, and ground
beef. This analysis also indicates that onions of any type are not linked to
this outbreak. Evaluation of additional information about the locations
of involved restaurants, the patterns of distribution of food ingredients, and
the characteristics and preparation of food ingredients indicates that shredded
lettuce consumed at Taco Bell restaurants in the northeastern United States was
the most likely source of the outbreak. Because multiple Taco Bell
restaurants were involved during the same time period, contamination of lettuce
likely occurred before reaching the restaurants. Health officials and the
restaurant chain are working collaboratively to learn more about the shredded
lettuce to determine how it may have become contaminated.
Health officials in Minnesota and Iowa are investigating a
separate outbreak of E. coli O157 infections associated with another
fast food restaurant chain. They are reporting 27 and 50 associated illnesses,
respectively. E. coli O157 strains isolated from patients in both
states have indistinguishable “DNA fingerprint” patterns, confirming that the
Iowa and Minnesota clusters are linked. This pattern is distinct from the Taco
Bell restaurant outbreak pattern. A strain that matches that of patients in
this new outbreak has also been isolated from an ill person in Wisconsin.
Investigators in Minnesota and Iowa have independently identified lettuce as
the contaminated food vehicle. Traceback efforts are underway. The most recent
onset of illness from a confirmed case in this outbreak is December 8, and this
outbreak is not considered over.
E. coli O157 causes diarrhea that is often bloody
and accompanied by severe abdominal cramps, but fever is typically absent or
mild. Persons who have developed such symptoms are advised to consult a
physician to request that a stool sample be tested for E. coli, and to inform
their local health department.
For more information
on E. coli infection and this outbreak, please refer to the following
website: http://www.cdc.gov/ecoli/