Some 70% of chickens being sold in UK grocery stores have tested positive for the presence of food poisoning bug campylobacter, according to the Food Standards Agency (FSA).

Asda sold the highest proportion of contaminated chicken (78%) followed by The Co-operative Food (73%), the results reveal. Around 28% of Asda’s chickens tested positive for campylobacter above the highest level of contamination (+1,000 colony forming units per gram) compared to the average of 18%.

Among independents, discounters and butchers, 76% of chickens tested positive, and 25% above the highest level of contamination.

The results are from the first two quarters of the FSA’s year-long survey of campylobacter on fresh chicken. Campylobacter is the most common form of food poisoning in the UK, affecting an estimated 280,000 people a year, but it is killed by thorough cooking. Poultry is the source of the majority of cases.

FSA director of policy, Steven Wearne, said retailers needed to do more to reduce the amount of campylobacter on fresh chickens. “Although we are only half-way through the survey, 18% of birds tested had campylobacter over 1,000 cfu/g, the highest level of contamination, and more than 70% of birds had some campylobacter on them,” he said.

“There are signs that some retailers are starting to step up their responsibilities. When more do, we will see the sustained improvements that will help prevent many of their customers getting ill.”

The Co-op has just introduced ‘roast in the bag’ chickens which help limit cross-contamination by minimising the handling of the raw chicken in the home.

Summary of results by retailers:

RetailerNumber of samples% skin samples positive for campylobacter (95%   confidence interval)% skin samples  >1,000 cfu/g campylobacter (95% confidence interval)% pack samples positive for campylobacter (95%   confidence interval)

Asda

312

78  (73 - 82)

28  (23 - 33)

12  (8 - 15)

The   Co-operative

171

73  (66 - 80)

19  (14 - 25)

5  (2 - 9)

M&S  

68

67  (55 - 78)

22  (13 - 33)

4  (0 - 10)

Morrison’s

179

69  (62 - 75)

21  (16 - 28)

9  (5 - 14)

Sainsbury’s  

300

69  (63 - 74)

14  (11 - 19)

3  (1 - 6)

Tesco

607

64  (61 - 68)

11  (9 - 14)

3  (2 - 4)

Waitrose  

70

69  (58  - 80)

16  (8 - 25)

9  (3 - 18)

Others*  

288

76  (71 - 80)

25  (20 - 30)

7  (4 - 10)

Total

1,995

70 (68 - 72)

18  (17 - 20)

6 (5 - 7)

 

*The ‘Others’ category includes supermarkets where the market share was deemed small using the 2010 Kantar data, ie Lidl, Aldi, Iceland, plus convenience stores, independents, butchers etc.