Test due to slash E.coli 0157 risk

Manufacturers could dramatically reduce the risk of E.coli 0157 outbreaks by using an extremely fast analysis process - or assay - due to launch later this year.

Alaska Food Diagnostics has developed an E.coli 0157 assay, which can get results in just eight hours. “Our competitors’ rapid tests take at least 24 hours and a standard test is five days, so the preliminary assay we’ve developed is the fastest on the market,” said Alaska’s head of microbiology research and development Pradip Patel.

By adding a pre-enrichment medium, the test uses immuno magnetic separation to reduce background organisms in the sample in order to define any E.coli cells in a six hour period.

The magnetic beads are then transferred onto a filter plate, a vacuum is applied under the plate and the beads are held in the filter. After a few washes to get rid of any background organisms, a bacterial virus specific to E.coli is added. The plate is incubated for an hour to allow the virus to infect the E.coli. Once the virus DNA is in the E.coli cell, it breaks it open and the components released from the E.coli can be collected. This eliminates the need for selective plating using petri dishes, which is usually required in standard tests.

“E.coli has been a huge problem, so the test has seen a great deal of interest and we’re currently working with salad suppliers in the UK and US,” said Patel. The firm is also working on a listeria assay, which will achieve results within one working day.