Proof of concept for a rapid, point of use test for Legionella pneumophila

Legionella is a bacterial disease transmitted as a consequence of breathing in aerosols from
water systems where the bacterium has been able to grow, including cooling towers, air
conditioners, showers, sinks, toilets and birthing pools. It is a mandatory requirement for
experts to assess the risk of Legionella in all buildings to which there is employee or public
access, including hospitals, hotels, workplaces and rented houses & offices. The current
method of screening for Legionella involves collecting a water sample and sending it to a
laboratory for testing, which takes 10-12 days to obtain a result. This project aims to develop a
rapid test for Legionella, which will allow expert contractors to collect and test water samples
at site to return a result within approximately 30 minutes. The test is based on specific
detection of Legionella bacteria and uses an innovative, patented capture and amplification
system to allow the test to detect low levels of bacteria in water samples. The presence of
bacteria is detected by a light-emitting reaction, which is read by a hand-held reader. This
reader is already reliably used to read results from environmental toxicity tests. The test will
need to detect < 100 to 1000 bacteria colony forming units per litre of water (cfu/L) as these
represent the two values after which action may either need, or must, be taken, respectively.
In response to recent HSE guidelines, some laboratories are detecting down to 40 cfu/L. In
order to achieve these levels of sensitivity, we will use a rapid, single-use device to
concentrate water samples at the site of collection to allow rapid detection and action if
required. The system could be incorporated into installation pipework for background checks
on system water and to validate proper temperature control. This approach will offer
significant public health benefits in the protection of the health of the public and in providing
better control in private & augmented health settings.