Every major retailer failed to meet targets to reduce levels of the bug campylobacter, the Food Standards Agency said.
It said results from the first six months of its year-long survey of fresh chickens found 70 per cent tested for campylobacter, with six per cent of packaging testing positive.
Detailed information about retailers published for the first time, reveals Asda sold the highest percentage of chickens contaminated with campylobacter at 78 per cent, with 12 per cent of packaging testing positive.
Almost three-quarters of chickens sold by the Co-operative tested positive, followed by Morrisons, Sainsbury’s and Waitrose (69 per cent), Marks & Spencer (67 per cent) and Tesco (64 per cent).
The consumer group Which? said supermarket bosses should “hang their heads in shame”.
Its executive director Richard Lloyd said: “These results are a damning indictment of supermarkets and consumers will be rightly shocked at the failure of trusted household brands to stem the tide of increasingly high levels of campylobacter.”
Retailers have announced a series of measures to limit the bug, with the Co-operative and M&S introducing “roast in the bag” chickens to minimise handling at home. Asda and its supplier Faccenda said they had committed to full-scale trials of new steam technology.
Asda said: “We take campylobacter seriously and it goes without saying that we’re disappointed with these findings. There is no ‘silver bullet’ to tackle this issue, but, along with other retailers, we’re working hard to find a solution.”
Campylobacter is the most common form of food poisoning in the UK, affecting an estimated 280,000 people a year. Poultry is the source of the majority of cases.