Attacking E.coli

A bacteriophage.Field trials in New Zealand for a new, natural control treatment specifically targeting E.coli O157:H7 are showing positive results.

E.coli O157 bacteria can affect human health and cause meat exports to be devalued or even rejected if detected in a shipment.

Over a decade of work on bacteria-specific viruses (bacteriophages or ‘phages’) that attack and destroy E.coli O157 by the Institute of Environmental Science and Research (ESR), in close association with the Meat Industry Association (MIA) and others, is moving towards commercialisation. This has taken the form of an E.coli control product, STECleanz®, which was launched at the Red Meat Sector Conference in July.

ESR business development manager Chris Litten explains further.

“Phages are naturally occurring and found everywhere – on the farm, on gumboots and in processing plants.

“However, they’re not sentinel and do not search out E.coli to deal with, rather they sit in the environment waiting for an O157 bacteria to pass by,” he says.

While other bacteriophage products are commercially available, particularly in the US, the New Zealand research has concentrated on finding the right mix of phages that occur naturally in New Zealand to target E.coli O157. STECleanz® – named for the shiga toxin producing E.coli serrogroups (STEC) – is the result.

MIA’s innovation programme manager Richard McColl says a large scale pre-commercialisation trial has been underway this season by the meat industry.

“This is a real game-changer and will protect many millions of dollars of investment,” he says.

Ten processing plants have been involved in trialling the treatment initially on bobby calves, as these had been found to have higher levels of E.coli than adult cattle.

Application was fairly simple, with the calves being sprayed under the tail and body with 50-100 mls of STECleanz®, 15 minutes before slaughter.

“Application only targets the harmful O157 bacteria and then it naturally biodegrades, without affecting the quality of the final product,” explains Litten.

“Anecdotal reports from the plants suggest that the trials have gone really well with some saying STECleanz® made a huge difference, intervening at source to dramatically lower the levels of O157 found at post-slaughter testing.

“It’s not the only thing the works are doing to combat E.coli, but it is an added assurance.”

One of the participants in the commercial trial was Greenlea Premier Meats.

Their business development manager, Julie McDade, says there are still several weeks of data to be analysed and/or reported so it is too early to make a final conclusion about the effectiveness of the product from their point of view.

“However, at this stage, it does appear promising.

“We certainly support the research into this product and would like to see it taken to the next stage of development.

“A product that is effective against all seven E.coli that meat processors are required to test for would be quite a powerful pre-harvest intervention,” Julie says.

This is the focus of current research work being undertaken at ESR.

Chris Litten believes that it has definitely been a good investment for the industry and provides a platform for new technologies using phages, including potentially for human health, which will also have application overseas.

The $4 million bacteriophages work has been principally funded by the MIA and the Ministry of Primary Industries (MPI) through the Meat Industry Initiatives Fund, a pan-industry fund supporting whole of industry research in the areas of food safety and market access.

The development of the treatment has been an excellent example of the science community working with industry to develop and commercialise a solution to a significant industry issue, says McColl.

This article has appeared in Food NZ magazine (October/November 2014) and is reproduced here with permission. More information about ESR’s work in the phages field is contained in the edition.

Be the first to comment

Leave a Reply