/ Food & Drink

Shocking levels of potentially deadly bug in chicken

After a year of testing the Food Standards Agency has today published its full results on the levels of potentially deadly Campylobacter found in supermarket chickens.

It found that nearly three-quarters of supermarket chickens are still being found contaminated with the bug, which could make you seriously ill or even kill you. This beggars belief.

Each year, it is estimated that 100 people die and an estimated 280,000 fall ill from Campylobacter. Today’s test results have shown that there has to be more done to bring down the levels in chicken.

Campylobacter action plans and what more must be done

We’ve been pressing the supermarkets to take action to make chicken safe, and publish their individual action plans on how they intend to bring down levels of Campylobacter.

So far, eight out of 10 of the supermarkets have published plans and told us what they are doing. We are satisfied they are taking the problem seriously and have ticked them off our Safe Chicken Checklist.

There are two remaining supermarkets that, whilst we are pleased to see they have published plans and shown that they take this problem seriously, we think need to do more to make their plans clearer.

Morrisons and Sainsbury’s need to be clearer on the detail of the actions they will take in future (not just what they’ve done so far), timescales for action, and that their CEOs have endorsed their plans.

The biggest food safety concern in the UK

The FSA says that Campylobacter contamination is now the biggest food safety concern in the UK. For supermarkets to be seen to be taking this seriously we would expect them to have published credible plans and to be getting on with reducing levels in their supply chains.


This Conversation is timely because the Food Standards Agency has now published cumulative results for whole chicken sold by supermarkets: http://www.food.gov.uk/news-updates/news/2015/14003/campylobacter-survey-results-12months

It’s encouraging to hear of actions but this is no time for complacency, since not one of these supermarkets has achieved the target set by the FSA. The best of the bad bunch is Tesco, where the percentage of heavily contaminated samples remains lower than the other retailers tested.

Although the problem arises at the farming and processing stages, the supermarkets are knowingly selling heavily contaminated chickens that can make large numbers of people sick, or worse, as Darren says in his introduction. I have been following the campylobacter issue since November and nothing that I have read gives me confidence that the industry is doing enough to tackle the long standing campylobacter problem. Thanks to Which? for keeping us updated.


Campylobacter was just described as a naturally occuring bacteria on the BBC News.
Are they correct in their description?


It’s a fair statement because the Campylobacter species that cause food poisoning in humans can be isolated from the environment. The intensive farming conditions encourage spread between animals and to new flocks introduced to an environment that is heavily contaminated. Sometimes the fact that campylobacter exists in the environment seems to be used as an excuse for the problem

Most bacteria can be described as naturally occurring. Exceptions would be those that are deliberately introduced, selected for certain characteristics, or genetically modified.


FSA results are an average over a year apparently, so does not seem to look at whether recent action plans have had any effect. If you look at M&S website their recent figures indicate they achieve half the FSA target. However we have had cold months that will no doubt reduce campylobacter naturally.
I have asked FSA whether they have data by supermarket by quarter, how winter affects data, whether they are going to continue sampling and whether they will sample and inspect the processors.


I should have thought that the high temperature [due to stock density] and the intense atmosphere under which broiler chickens are reared would be conducive to the rapid multiplication of any bacteria, Winter notwithstanding.


The benefit of looking at the data for a year is that the number of samples is more statistically significant, as can be seen from comparing the confidence intervals for the cumulative data with those for the data published last November. FSA is going to continue their studies next year according to what is on the page I provided a link to.

I am disappointed that the FSA have ignored my advice to publish their data in a form suitable for the general public – which means using a visual presentation and avoiding terms such as cfu/g and confidence interval. As it stands, the information is not easy for the general public to understand. M&S does adopt a visual approach, which is commendable despite the unusual format, but fails to explain terms such as >1000. The use of red/amber/green draws attention to the heaviest contamination. FSA now says “The highest band (>1000 cfu/g) is the primary focus of attention”, though this point needs to be highlighted when data are published.

The FSA makes it clear that interventions are needed throughout the entire process, so I agree that the processors should be inspected. With most chicken processed by two major companies, the job should be much less onerous than inspecting the numerous farms.


John – I take your point about the effect of temperature on the multiplication of bacteria, but it’s not that simple. Inside the chicken the temperature is constant, irrespective of ambient temperature. Outside, most of the campylobacter will be in faeces, which will dry more quickly in warm conditions, arresting growth and probably killing many of the bacteria.


Thanks Wavechange – I hadn’t thought of that. So a less-intensive husbandry might actually be worse in terms of bacterial infection?


I don’t know, John. The point I made is just one of many factors that could be involved. In an earlier Conversation, you mentioned your visit to see broiler production. My understanding is that transmission is primarily via the faecal-oral route, i.e. the birds eat or drink contaminated material. Unlike humans, the chickens don’t get ill but campylobacter grows in their intestines and their waste is heavily contaminated. During the mass processing of carcasses, the waste gets everywhere, contaminating birds that don’t carry campylobacter, and inadequate cleaning means that contaminated chicken ends up on the supermarket shelves.

I hoped to find evidence that less intensive production such as organic farming might help address the problem, but the longer lives and lack of use of growth-promoting antibiotics seems to offset the benefits.


“The benefit of looking at the data for a year is that the number of samples is more statistically significant”. FSA tested 130 samples for M&S. The M&S report tested 487 samples in an independent FSA approved laboratory on samples taken from stores at random. Seems a shame such results, and no doubt those from other stores, were not taken into account by FSA to give more meaningful results.
From what is said, winter might be a worse time for spreading campylobacter? I have seen contrary statements elsewhere, so it would be useful to clarify this. Trend is important, not average, to see if they are making any progress.


We will start to see trends when the results from the the second year of study become available. Seasonal differences have been documented but there are so many possible differences in animal husbandry that I cannot see much possibility of deriving useful information from seasonal differences unless it can be shown that one broiler shed is performing significantly better than others.

It’s possible that the additional tests done for M&S were done in different labs, in which case if would not be appropriate to compare them. Having supervised technicians carrying out the apparently simple process of doing bacterial counts I’m aware that it is a challenge to produce reproducible data.

I would be interested to know if there is any obvious reason why Asda chickens are substantially contaminated than those from Tesco, i.e. look at the biggest difference.


We need to know sooner rather than later whether actions are having a significant effect – not waiting yet another year. All availabnle data should be used – the FSA can decide whether M&S and other stores results are valid. “Methodology – based on a total sample of 487 M&S chickens. The tests are carried out by FSA approved independent testing laboratory Campden BRI.
The chickens tested are taken at random from the shelves of M&S stores across the UK”.


The FSA should decide whether or not it would be appropriate to use these data. They will have access to information that we don’t. Advertising is full of inappropriate comparisons and one of my personal hates is inappropriate use of data.