|
ISS
820 East 20th Street
Cookeville, TN 38501 USA
931 526 1106
Bob@sproutnet.com
中文版
En espaņol
| |
Alfalfa Sprouts
and Salmonella Kottbus Infection: A Multistate Outbreak Following Inadequate
Seed Disinfection with Heat and Chlorine
January 2003
Journal of Food Protection: Vol. 66, No. 1, pp. 1317
K. L. Winthrop,a, c M. S. Palumbo,b J. A. Farrar,b J. C. Mohle-Bohle-Boetani,a
S. Abbott,a M. E. Beatty,c, d G. Inami,a and S. B. Wernera
-
California Department of
Health Services, Division of Communicable Disease Control, 2151 Berkeley Way,
Berkeley, California 94704
-
California Department of
Health Services, Food and Drug Branch, 601 North 7th Street, MS 357, P.O. Box
942732, Sacramento, California 94234
-
Epidemic Intelligence Service,
Epidemiology Program Office, Centers for Disease Control and Prevention, 1600
Clifton Road, Atlanta, Georgia 30333
-
Foodborne and Diarrheal
Diseases Branch, Division of Bacterial and Mycotic Diseases, Centers for
Disease Control and Prevention, 1600 Clifton Road, Atlanta, Georgia 30333, USA
ABSTRACT
Raw sprouts have been implicated in a number of foodborne disease outbreaks.
Because contaminated seeds are usually responsible, many sprout producers
attempt to disinfect seeds before germination and detect sprout contamination
during production. In March 2001, we detected an increased number of Salmonella
serotype Kottbus isolates in California. Overall, we identified 31 cases from
three western states. To identify the cause, we conducted a case-control study
with the first 10 identified case-patients matched to 20 controls by age, sex,
and residential area. Our case-control study found illness to be statistically
associated with alfalfa sprout consumption. The traceback investigation
implicated a single sprouter, where environmental studies yielded Salmonella
Kottbus from ungerminated seeds and floor drains within the production facility.
Pulsed-field gel electrophoresis patterns of all patient, seed, and floor drain
Salmonella Kottbus isolates were indistinguishable. Most implicated sprouts were
from seeds that underwent heat treatment and soaking with a 2,000-ppm sodium
hypochlorite solution rather than the Food and Drug Administration
(FDA)-recommended 20,000-ppm calcium hypochlorite soak. Other implicated seeds
had been soaked in a calcium hypochlorite solution that, when tested, measured
only 11,000 ppm. The outbreak might have been averted when screening tests of
sprout irrigation water detected Salmonella in January; however, confirmatory
testing of these samples was negative (but testing improperly utilized
refrigerated irrigation water). Producers should use the enrichment broth of
positive screening samples, not refrigerated irrigation water, for confirmatory
testing. Until other effective disinfection technologies are developed,
producers should adhere to FDA recommendations for sprout seed
disinfection.
|