Persistence of Shiga toxin-producing Escherichia coli O26 in cow slurry.
OBJECTIVE
The main objective of this study was to evaluate the growth and survival of Shiga toxin-producing Escherichia coli (STEC) O26 in cow slurry; this serogroup is regarded as an important cause of STEC-associated diseases.


RESULTS
Four STEC were examined by polymerase chain reaction (PCR) to determine whether they harbour key virulence determinants and also by pulsed-field gel electrophoresis (PFGE) to obtain overview fingerprints of their genomes. They were transformed with the pGFPuv plasmid and were separately inoculated at a level of 10(6) CFU ml(-1) in 15 l of cow slurry. All STEC O26 strains could be detected for at least 3 months in cow slurry without any genetic changes. The moisture content of the slurry decreased over time to reach a final value of 75% while the pH increased from 8.5 to 9.5 units during the last 50 days.


CONCLUSIONS
STEC O26 strains were able to survive in cow slurry for an extended period.


CONCLUSIONS
Long-term storage of waste slurry should be required to reduce the pathogen load and to limit environmental contamination by STEC O26.
Fremaux
B
B
Unité de Microbiologie Alimentaire et Prévisionnelle-Ecole Nationale Vétérinaire de Lyon 69280, Marcy l'Etoile, France. b.fremaux@vet-lyon.fr
Prigent-Combaret
C
C
Delignette-Muller
M L
ML
Dothal
M
M
Vernozy-Rozand
C
C
D000818:Animals; D002417:Cattle; D015169:Colony Count, Microbial; D004926:Escherichia coli / Q000145:classification / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D008372:Manure / Q000382:microbiology*; D010957:Plasmids; D022603:Shiga Toxins / Q000096:biosynthesis*; D013997:Time Factors
D008372:Manure; D022603:Shiga Toxins; D049452:Green Fluorescent Proteins