Validation of PVT VIABLE® for Detection of Legionella in Potable and Non-Potable Water: AOAC Performance Tested Method SM 082303

Published on 02/21/2024 | by Waterline Admin

Wickenberg L, Gabrie K, McCarthy P, Cain M. J AOAC Int. 2024 Jan 4;107(1):120-128. doi: 10.1093/jaoacint/qsad112. PMID: 37740955.


  • Phigenics Validation Test (PVT) VIABLE® (Viability Identification Assay by Legionella Enrichment) is a method to detect viable legionella bacteria in building water systems.
  • PVT VIABLE was validated against ISO 11731:2017 Water Quality-Enumeration of Legionella reference method for the detection of viable Legionella species in potable and non-potable water.
  • PVT VIABLE was tested for inclusivity (n = 50 strains of legionella) and exclusivity (n = 30 non-target strains), robustness, and stability. A multi-laboratory instrument variation study was performed to evaluate the PCR data. The matrix study was performed on potable and non-potable water samples inoculated with Legionella pneumophila at a low (n = 20) and high fractional level (n = 5). Samples were analysed using the PVT VIABLE and confirmed using ISO 11731:2017.
  • Statistical analysis showed no difference between PVT VIABLE and ISO 11731:2017 for 100 mL test portions of potable and non-potable water.
  • PVT VIABLE demonstrated high levels of specificity and sensitivity in the inclusivity and exclusivity study. Results of the robustness and stability studies demonstrated the method was sufficiently robust to handle small method changes and met the method claims of stability.
  • PVT VIABLE allows the end user to obtain presumptive results for viable Legionella spp. contamination of potable and non-potable water in 2-3 days.
  • This novel diagnostic tool also differentiates between L. pneumophila sg1, L. pneumophila sg2-15, and Legionella spp. without the need for additional confirmation steps as outlined in ISO 11731:2017.
  • The paper can be sourced here

    Diary Dates & Events

    Grime Scene


    Following on from the successful Grime Scene competition, we have decided to continue the theme for another year, but with a twist. This year, we are asking for photographs of the grimiest pictures you can find accompanied with another photograph of how the ‘scene’ has been improved by your maintenance or cleaning.

    We will display the photographs in each of the Waterline editions throughout 2024. The ‘most improved’ picture will be chosen by WMSoc members via an online vote. The winner will receive a £25 Amazon Gift Voucher after the Winter 2024/25 edition has been published.

    Please send your photographs to:
    [email protected].

    Product & Service Spotlight

    Secondary disinfection options from B & V Chemicals:

    We can offer our customers several secondary disinfection options to control issues like biofilm formation and harmful bacteria proliferation

    Genox or chlorine dioxide
    For water usage above 60m³/day, we recommend installing either a chlorine dioxide unit or a Genox unit. The Genox units generate hypochlorous acid from brine electrolysis with running costs as low as 4.0 pence/m³.

    Ultralox 40 or SuPerSil
    For smaller systems, continuous dosing with Ultralox 40, a hypochlorous acid solution, is a cost-effective alternative with few safety risks.
    Similarly, silver peroxide dosing suits low to medium water usage systems.

    For more information contact [email protected]

    How the NEW SolidTek® Biocide Feeder Package will BENEFIT YOU

    SolidTek® has launched its NEW Biocide Feeder which is functional, compact, and environmentally-friendly.

    Designed for use with SolidTek’s® enhanced bromine biocide, BromTek, it offers multiple benefits:

    Reduced exposure to fumes and bromine dust (non-pressurised system).

    Use with field proven mixed hydantoin biocide - better performance than standard bromine tablets.

    Wall mounted reducing footprint of installation.

    Charge with product in under 5 minutes without isolation from the system.

    Product calculators and tech support available.

    Lovibond MD640 Photometer (PTSA & Fluorescein capable)

    Product Spotlight Drop Test Kits

    How many times have you heard … ‘we’re not sure what the system volume is’. A common problem which can be expensive - wasting chemical over dosing, or underdosing so the treatment is ineffective (i.e. shock dosing a biocide). The MD640 photometer has PTSA & Fluorescein capability built in. Simply use our System Checkers to add to an unknown system and read a PTSA or Fluorescein levels to accurately identify the system volume.

    The Hydrosense PRO range


    The Hydrosense PRO range pioneers Legionella pneumophila detection, the cause of over 97% of Legionnaires’ disease outbreaks, by identifying all the serogroups 1-15 of this dangerous Legionella species. This easy-to-use, highly sensitive test uses unique filtration, offering a three-line test result that distinguishes between serogroup 1 and serogroups 2-15 within 25 minutes. The water test has a level of detection of 100 CFU/L and swab tests detect 200 CFU per swabbed area, providing crucial, rapid insights for water safety management.

    TME Thermometers

    Save time and money on your ACoPL8 testing with TME’s innovative legionella solutions.
    • Perform faster temperature tests with our MM2008 Thermometer with integral timer for running of hot and cold water taps.
    • Simplify concealed TMV testing with our TC Wall Port, a remote access point for temperature sensors you can install yourself. Once in place, take instant readings from a more convenient location – no more climbing ladders or removing panelling.
    • Update to paperless recording with our MM7000-2D Barcode Scanning Bluetooth Thermometer.
    • Get FREE UKAS traceable calibration certificates.
    • Visit our NEW website for 25% OFF all online orders placed by 30th June 2024.

    [email protected]

    01903 700651