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HSE-PHL-Dublin Increased Prevalence and diversity of VTEC in Ireland: Fact of Artifact? Dr Anne Carroll Dr Eleanor McNamara
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HSE-PHL-Dublin PHL Scope Official testing laboratory, Food and water (S.I. 85 of 1998 and S.I. 117 of 2010). Accredited ISO 17025 National VTEC diagnostic and typing service (Clinical, foods water environmental) Clinical diagnostic general microbiology service, hospital/GP
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HSE-PHL-Dublin National VTEC Service Stools, Food, Water. Isolate Confirmation Accredited PCR >22,000 tests PFGE VTEC Reference Service
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HSE-PHL-Dublin VTEC incidence
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HSE-PHL-Dublin VTEC incidence
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HSE-PHL-Dublin
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2011 VTEC serogroups 2002-2011 33 serogroups + 2011: 17 serogroups 15 clinical +2 food
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HSE-PHL-Dublin 2011 HPSC VTEC subgroup HPSC Ref lab 5 labs Public health Consensus + recommend standardised methods for VTEC
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HSE-PHL-Dublin Risk USAROIScotlandE&WNordic Bloody diarrhoea HUS Isolates OB contacts symptomatic Community acq Diarrhoea (O157) ? (O157) (optimal) Food handler Abdominal Cramps Contact with ruminants Consumption raw animal products or raw fruits/veg Contact with animal products e.g. manure Hospitalised
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HSE-PHL-Dublin “all stools submitted for routine testing from patients be simultaneously cultured for O157 and tested with an assay that detects Shiga toxins to detect non-O157 STEC” “Specimens or enrichment broths in which Shiga toxin or STEC are detected but from which O157 STEC are not recovered should be forwarded as soon as possible to a state or local public health laboratory”. Lab Methods US
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HSE-PHL-Dublin Lab Methods ROI MethodRisk123456 CT-SMAC /Chrom High Low Agglutination O157 High Low EnrichmentHigh (outbreakO157) Low IMSHigh (outbreakO157) (O157, O26, O111) Low Non-O157 agglutination High Low O157 gene detection High Low VT gene detection High Low
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HSE-PHL-Dublin Lab 1 MethodRisk1 CT-SMAC /Chrom High Low Agglutination O157 High Low EnrichmentHigh Low IMSHigh Low Non-O157 agglutination High Low O157 gene detection High Low VT gene detection High Low
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HSE-PHL-Dublin Lab 1 MethodRisk1 CT-SMAC /Chrom High Low Agglutination O157 High Low EnrichmentHigh Low IMSHigh Low Non-O157 agglutination High Low O157 gene detection High Low VT gene detection High Low 2012
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HSE-PHL-Dublin 2012201120102009 Jan-Apr14 (3xO103, 1xO111, 5x ungp, 1x O145, 4xO26) 001 (1x O105 ac) Whole year 4 (1x ungp, 1x O150, 1x O91, 1x O26) All picked up by ref lab as part of O157 OB screen 4 (1xO121, 3x O26) 12 (1x O105 ac, 4x ungp, 1x O145, 1x O103, 1x O178, 4x O26) 7 picked up by ref lab as part of OB screen Pre 2012 samples referred to ref lab based on risk and not lab findings (stools).
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HSE-PHL-Dublin Lab 7 MethodRisk7 CT-SMAC /Chrom High Low Agglutination O157 High Low EnrichmentHigh Low IMSHigh Low Non-O157 agglutination High Low O157 gene detection High Low VT gene detection High Low
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HSE-PHL-Dublin Lab 7 MethodRisk7 CT-SMAC /Chrom High Low Agglutination O157 High Low EnrichmentHigh Low IMSHigh Low Non-O157 agglutination High Low O157 gene detection High Low VT gene detection High Low STEC CHROMagar
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HSE-PHL-Dublin 2012201120102009 Jan-Apr10 (2x O145, 7x O26, 1x ungp) 1 (1xO26) 02 (2xO26) Whole year 4 (3x O26, 1x O5) O5 picked up by ref lab as part of OB screen 3 (1xungp, 2xO26) 3 (3xO26) Pre 2012 samples referred to ref lab primarily based on lab findings and not risk (Isolates)
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HSE-PHL-Dublin MethodRisk2 CT-SMAC /Chrom High Low Agglutination O157 High Low EnrichmentHigh Low IMSHigh Low Non-O157 agglutination High Low O157 gene detection High Low VT gene detection High Low Lab 2 No changes to methods
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HSE-PHL-Dublin 2012201120102009 Jan-Apr14 (14x O26) 12 (9xO26, 3xO146) 2 (2xO26) 4 (4xO26) Whole year 41 (28x O26, 1x O150, 1xO44, 2xO5, 1xO76, 3xO146, 5x ungp) 27 (27xO26) 12 (5xO26, 3xungp, 2x O121, 2x O132) samples referred to ref lab based on both lab findings and risk (stools and isolates)
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HSE-PHL-Dublin Issues PCR Direct from stool PCR pos culture negative issue Direct detection of vt1 or vt2 gene(s) (without strain isolation), probable or confirmed depending on clinical criteria (HPSC)
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HSE-PHL-Dublin Ref lab Direct PCR, Enrichment/IMS PCR, colony confirmation. 1. Direct PCR pos and/or Enrichment/IMS PCR pos + colony confirmed 2. Direct PCR pos + Enrichment/IMS PCR pos but can’t isolate colony 3. Direct PCR pos + Enrichment/IMS PCR neg Do 2 +3 have the same PH implications? Issues
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HSE-PHL-Dublin 2) Direct PCR pos + Enrichment/IMS PCR pos but can’t isolate colony Organism seems to be growing viable Shedding of viable organism possible PH risk Source of infection
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HSE-PHL-Dublin 3) Direct PCR pos + Enrichment/IMS PCR neg Organism not growing not viable Shedding of non viable organism not a PH risk May have been infection with organism subsequently dying source of infection May have been no infection but ingestion of non viable organism e.g. from treated water or processed food
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HSE-PHL-Dublin If Use PCR only result (2 or 3) may not be true result O26 vt2 PCR pos O26 vt2 O26 vt neg + other serogroup vt2 pos O26 vt2 + other serogroup vt2 pos
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HSE-PHL-Dublin Challenges Methods Risk Transport Facilities IT
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HSE-PHL-Dublin Summary VTEC in recent years Particularly in non-O157 VTEC Introduction of mandatory notification Increased awareness non-O157 VTEC Recent increases of non-O157 VTEC can be attributed to more targeted methods Challenges Clinical and lab findings need to be taken together Lab + PH need to communicate
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HSE-PHL-Dublin Thank You Thank you to dedicated PHL Staff
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HSE-PHL-Dublin Outbreak Service Primary High Risk sample analysis Confirmation and Typing Medical advisory service OCT Data collation VTEC Reference Service
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