E. coli O157, spinach - USA (multistate)(07)

International Society for Infectious Diseases
<http://www.isid.org>

[1]
Source: CNN.com [edited]
< http://www.cnn.com/2006/HEALTH/09/21/tainted.spinach.ap/>


Health authorities hunting the source of a nationwide _E. coli_
[O157:H7] outbreak are focusing on 9 California farms after
discovering what could be a crucial clue: an opened bag of spinach
left in the refrigerator of someone sickened by the bacteria.

The bag of tainted Dole baby spinach is the "smoking gun" that has
allowed investigators to zero in on 3 counties in California's
greater Salinas Valley, said Dr. Mark Horton, the state public health
officer. Authorities also were checking processing plants, Horton said.

Officials said consumers still shouldn't eat bagged spinach, even as
they closed in on the source of the bacteria as likely somewhere in
Monterey, San Benito or Santa Clara counties. The bag of fresh
spinach that tested positive for _E. coli_ was found in New Mexico,
and other bags recovered elsewhere in the country also were being tested.

"It's certainly premature to say only this bag is going to test
positive," said Dr. David Acheson of the FDA's Center for Food Safety
and Applied Nutrition. "There are others in the works."

New Mexico Department of Health officials confirmed the tainted bag
of spinach was found after a person who ate some of the leafy greens
became 1 of 146 people in 23 states sickened by the outbreak, and 1
person has died.

The spinach tested positive for the same strain of _E. coli_ linked
to the outbreak, Acheson said. Dole is one of the brands of spinach
recalled Friday by Natural Selection Foods LLC of San Juan Bautista,
California.

The tainted greens -- conventionally grown spinach and not organic --
came from one of the farms that supplies spinach to Natural
Selection, said Samantha Cabaluna, spokeswoman for Natural Selection.

Government and industry officials were working on how to allow
spinach grown elsewhere back on the market, Acheson said.

New Jersey Democratic Sens. Robert Menendez and Frank R. Lautenberg
urged the FDA to assure the public spinach grown in their state was
safe.  "As the nation's 4th-largest spinach producer, spinach farming
is a multimillion-dollar industry for the Garden State," Menendez
said. "That is why we are imploring the FDA to move quickly in
identifying the source of the infected spinach."

Investigators began visiting farms in the Salinas Valley on Tue, 19
Sep 2006, seeking signs of past flooding or cases in which
contaminated surface areas had come into contact with crops. They
also were looking for potential sources of bacteria inside packing
plants.  California produces 74 percent of the nation's fresh spinach crop.

Among those sickened, 71 percent were women. Among those victims who
could provide a date, they reported falling sick between 19 Aug and 5
Sep, according to the Centers for Disease Control and Prevention.

New Mexico's public health laboratory isolated _E. coli_ from the bag
of opened spinach and then completed "DNA fingerprinting" tests late
Tue, 19 Sep 2006. State and federal officials then matched it to the
strain of the bacteria, _E. coli_ O157:H7, implicated in the outbreak.


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[2]
Source: FDA.gov [edited]
<http://www.fda.gov/bbs/topics/NEWS/2006/NEW01459.html>


Case Reports:
To date, 146 cases of illness due to _E. coli_ [O157:H7] infection
have been reported to the CDC), including 23 cases of Hemolytic
Uremic Syndrome (HUS), 76 hospitalizations, and 1 death. Illnesses
continue to be reported to CDC. This is considered to be an ongoing
investigation.

States Affected:
Arizona and Colorado have just been added to the list of states with
confirmed cases.  There are now 23 affected states:  Arizona,
California, Colorado, Connecticut, Idaho, Illinois, Indiana,
Kentucky, Maine, Michigan, Minnesota, Nebraska, Nevada, New Mexico,
New York, Ohio, Oregon, Pennsylvania, Utah, Virginia, Washington,
Wisconsin, and Wyoming.

Laboratory Findings:
The New Mexico Department of Health announced today that it has
linked a sample from a package of spinach with the outbreak strain of
_E. coli_ O157. The spinach was eaten by one of New Mexico's patients
before becoming sick. DNA fingerprinting tests determined that the
strain from the spinach matches the strain from patients in the
outbreak. The package of spinach that tested positive was "Dole Baby
Spinach, Best if Used by Aug 30."


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[3]

Having followed the development of this outbreak with interest, I
wonder whether there has been any attempt to determine if other STEC
[Shiga toxin-producing _E. coli_, a synonym for VTEc - Mod.LL]
serotypes are also present. We have shown some time ago that in an
outbreak, the severity of the clinical condition was directly related
to the number of STEC 'O' antibodies produced by the patients,
suggesting that the outcome was related to the number of infecting
STEC serotypes (1). In other studies we have shown that the fecal _E.
coli_ flora of cattle is very diverse and can contain a variety of
STEC serotypes (2). Finally, food like spinach, that is somehow
contaminated by STEC, may also carry other enteric pathogens such as
viruses and we have reported combined STEC and Norovirus outbreaks (3).

I would therefore strongly urge the investigators of this outbreak to
include an examination for the presence of other STEC as well as
other enteric pathogens, especially viruses.

1. Kulkarni H, Goldwater PN, Martin A,Bettelheim KA: Escherichia coli
'O' group serological responses and clinical correlations in epidemic
HUS patients. Comp Immunol Microbiol Infect Dis. 2002;25: 249-68.

2. Bettelheim KA, Kuzevski A, Gilbert RA, et al: The diversity of
Escherichia coli serotypes and biotypes in cattle faeces. J Appl
Microbiol 2005;98: 699-709.

3. Bettelheim KA, Bowden, DS, Doultree J, et al: Combined infection
of Norwalk-like virus and Verotoxin-producing bacteria associated
with a gastroenteritis outbreak. J Diarrh Dis Res 1999;17: 34-36.

--
Karl A. Bettelheim