ecoli bacteria food safety

The regulator this week updated guidance to remind consumers to wash fresh produce

Evidence is mounting that last week’s announcement of a major e.coli outbreak across the UK could be linked to fresh salads.

One senior food industry source this week told The Grocer that the lead the FSA was currently focused on was fresh produce via sandwiches and salads, and from their understanding the FSA was not currently looking at cheese. 

While the regulator declined to confirm this, it did release further public guidance on Tuesday urging consumers to wash fresh produce.

“Fruit & vegetables should be washed with water before they are eaten to make sure that they are clean,” said head of incidents and resilience Darren Whitby. “This should be done under a running tap, or in a bowl of fresh water.”

The food safety watchdog said it was carrying out extensive food chain analysis and tracking food exposure information from people who had suffered illness linked to the outbreak.

“Based on what we currently know, it is most likely linked to one or more food items,” Whitby added.

Last week, the UK Health Security Agency reported 113 confirmed cases of Shigatoxigenic (STEC) e.coli.

In recent months, the variant of the bacterium has been linked to cheese, including a case at Christmas that was linked to more than 30 cases. 

However, Bronwen Percival, technical director at Neal’s Yard Dairy, said cases linked to raw milk cheeses were exceptionally rare.

“This is a problem for fresh produce generally and really one of the biggest sources is undercooked meat or fresh produce like salad vegetables,” she said.

The last major e.coli outbreak linked to fruit & veg was in 2011, traced back to northern Germany. It saw a significant e.coli outbreak linked to fresh vegetables that led to 800 severe cases and 53 deaths across Europe.

Shortcomings around testing

“There are certain strains of STEC that we don’t have the capacity currently to monitor properly and that’s a worry,” said Percival.

She also expressed concerns about the viability of the testing available to food producers.

“The testing that’s available is extraordinarily expensive and not widely available at all, and in fact the only ones who have the capacity to test for these pathogens are government labs, and you can’t use government labs generally as commercial laboratories.” 

This differs to other pathogens for which producers have testing programmes in place, such as for listeria.

Percival added that the ISO test for STEC was also “pretty useless” when it came to cheese as it can produce a large number of presumptive positives that ultimately turn out to be negative, and conversely, “when you test 25g of a batch of cheese, you don’t necessarily have the proof that it’s not there”.

The food sector needed “better tests that can either can either alert us to a problem or put our minds at ease and currently, the testing that’s available doesn’t do either of those things,” she said.  

However, “the health system is capable of doing much better analysis of the samples that are coming in and they’re more capable of detecting outbreaks, but that doesn’t mean it’s a straightforward process to then trace that back to a food vehicle”, she added.

“I would say the vast majority of those cases probably never do get traced back to source.”