Almost three quarters of shop-brought chickens are contaminated with a strain of bacteria which causes food poisoning, with almost a fifth testing positive at the highest level, the Food Standards Agency (FSA) has revealed.
The overall rate of contamination from campylobacter has risen from 70 per cent in November and 59 per cent in August, the FSA reported as it revealed results from the first three quarters of its year-long survey of fresh chickens.
Some 73 per cent of fresh shop-bought chickens are contaminated with the food poisoning bug.
Poultry is the major source of campylobacter, causing the FSA to urge the industry to make an effort to ensure chickens are free of the bacteria when they hit shoppers' baskets.
But the organisation has reported that no major retailers were meeting the target for reducing campylobacter – the most common cause of food poisoning which affects an estimated 280,000 people a year.
However, the FSA praised Marks and Spencer’s efforts to bring down contamination levels, and suggested others should follow suit.
The proportion of chickens testing positive of campylobacter - or 1,000 colony forming units per gram (cfu/g) - has risen from almost a 18 per cent in November to 19 per cent, while 7 per cent of packaging tested positive - up from 6 per cent in August.
When individual major supermarkets were considered, the FSA found that Asda once again sold the highest percentage of chickens contaminated with the food bug at 78.9 percent, with 31.1 percent showing the bug above the highest level of contamination and 13 percent of packaging testing positive.
In November, the supermarket acknowledged in a statement the problem was serious, but added: "There is no ‘silver bullet’ to tackle this issue, but along with other retailers, we’re working hard to find a solution."
Following closely behind was Morrisons, at 76.2 per cent, The Co-operative and Marks & Spencer, both around three quarters, Waitrose at 71.7 per cent, Sainsbury's 69.6 percent, and Tesco 68.2 per cent.
While individual figures for the discount supermarkets Aldi, Lidl and Iceland were not reported because their market share was based on 2010 figures and deemed too small, the overall rate of campylobacter contamination among all retailers other than the major supermarkets was 76.9per cent.
The FSA’s full set of results, by which point it will have tested around 4,000 samples of whole chickens bought from UK retail outlets and smaller independent stores and butchers, are expected to be published in May.
FSA director of policy Steve Wearne said: "We now know it is possible to make positive inroads in the reduction of campylobacter.
"Figures released today by M&S show that their intervention plan has resulted in fewer contaminated chickens on sale in their stores. If one retailer can achieve this campylobacter reduction through systematic interventions then others can, and should.
"Our survey is putting pressure on retailers to work with poultry processors to do more to tackle campylobacter. We want the industry to reduce the number of the most highly contaminated chickens as we know this will have the greatest impact on public health.
"Campylobacter is killed by thorough cooking, but it should not be left to consumers to manage the risk.
Richard Lloyd, director of the Which? consumer group called the current levels of contamination "unacceptable".
"While four major supermarkets have made their action plans public - The Co-operative, M&S, Tesco and Waitrose - the remaining three have yet to say how they're planning to tackle this bug.
"People need reassurance that supermarkets are doing everything they can to make chicken safe. The remaining retailers must publish their plans and commit to action now before consumers lose confidence in them."
Huw Irranca-Davies, shadow food and farming minister, labelled the results "disappointing", particularly after the horsemeat scandal.
"Consumers will rightly expect that all retailers take this issue extremely seriously and put in place robust measures to tackle the industry-wide challenge of reducing levels of contaminated chickens.
"After the horsemeat scandal and the recent allegations of hygiene failings in the poultry industry we need a better plan to restore confidence in the food sector. Labour will make sure that a transparent Food Standards Agency puts the consumer first and is able to challenge the industry to improve standards."
Additional reporting by PAReuse content