TABLE 1.

Detection of EHEC-associated genetic markers in 400 raw-milk cheese samples

Genetic markers targeted by real-time PCR (either alone or in combination with each other)Positive samples/400 tested
No.%
Individual markers
    stx11929.8
    eaea14937.3
    eae-β18721.8
    eae-γ151.3
    eae-ε112.8
    eae-γ2/θ6215.5
    eae-β1, eae-γ1, eae-ε, eae-γ2/θb129c32.3
    wzxO264511.3
    wzxO1039523.8
    wbdIO11110.3
    ihp1O14518345.8
    rfbEO157205
    wzxO26, wzxO103, wbdIO111, ihp1O145, rfbEO157d22155.3
    fliCH224461.0
    fliCH723458.5
    fliCH826265.5
    fliCH1119749.3
    fliCH2815438.5
    fliCH2, fliCH7, fliCH8, fliCH11, fliCH28e34987.3
Combinations of markers
    stx-eae6817
    stx-wzxO26-eae225.5
    stx-wzxO26-eae-β1194.8
    stx-wzxO26-eae-β1-fliCH11194.8
    stx-wzxO103-eae317.8
    stx-wzxO103-eae-ε51.3
    stx-wzxO103-eae-ε-fliCH251.3
    stx-wbdIO111-eae00
    stx-wbdIO111-eae-γ2/θ00
    stx-ihp1O145-eae5112.8
    stx-ihp1O145-eae-γ130.8
    stx-ihp1O145-eae-γ1-fliCH2830.8
    stx-rfbEO157-eae41
    stx-rfbEO157-eae-γ110.3
    stx-rfbEO157-eae-γ1-fliCH710.3
    stx-(wzxO26, wzxO103, wbdIO111, ihp1O145, rfbEO157)f8922.3
    stx-(wzxO26, wzxO103, wbdIO111, ihp1O145, rfbEO157)-eaeg6115.3
    stx-(wzxO26, wzxO103, wbdIO111, ihp1O145, rfbEO157)-(eae-β1, eae-γ1, eae-ε, eae-γ2/θ)h5413.5
    stx-wzxO26-eae-β1, stx-wzxO103-eae-ε, stx-wbdIO111-eae-γ2/θ, stx-ihp1O145-eae-γ1, stx-rfbEO157-eae-γ1i26j6.5
  • a Detection of the eae gene with universal primers/probe.

  • b Detection of at least one of the four eae variants eae-β1, eae-γ1, eae-ε, and eae-γ2/θ.

  • c Twenty-two samples contained eae-β1 and eae-γ2/θ; two samples contained eae-β1 and eae-ε; two samples contained eae-ε and eae-γ2/θ; one sample contained eae-β1 and eae-γ1; two samples contained eae-β1, eae-γ2/θ, and eae-ε; and two samples contained eae-β1, eae-γ2/θ, and eae-γ1.

  • d Detection of at least one of the five serogroup genetic markers wzxO26, wzxO103, wbdIO111, ihp1O145, and rfbEO157.

  • e Detection of at least one of the five fliC alleles specific for H2, H7, H8, H11, and H28 flagellar antigens.

  • f Detection of stx and at least one of the five serogroup genetic markers.

  • g Detection of stx, at least one of the five serogroup genetic markers and eae.

  • h Detection of stx, at least one of the five serogroup genetic markers, and at least one of the four eae variants.

  • i Detection of at least one of the five stx-serogroup-eae variant marker combinations.

  • j Two samples contained two combinations of markers each (i.e., stx-wzxO26-eae-β1 plus stx-ihp1O145-eae-γ1 and stx-ihp1O145-eae-γ1 plus stx-rfbEO157-eae-γ1).