The percentage of chickens positive at the top level for Campylobacter in the United Kingdom has increased for the second successive quarter.

For the top nine retailers, 3.6 percent of fresh whole chickens tested from April to June 2019 had more than 1,000 colony forming units per gram (CFU/g) of Campylobacter.

The figure for the previous results from January to March 2019 was 3.5 percent, from October to December 2018 it was 3.1 percent and for July to September, it was 3.5 percent. It is slightly lower than the number in the April to June period last year when 3.7 percent of chickens were positive for the highest level of Campylobacter.

Campylobacter is the most common cause of food poisoning in the U.K. with an estimated 280,000 cases annually. The infectious dose can be as low as a few hundred cells.

Results by the level of contamination

A recent Food Standards Agency report found Campylobacter at more than 1,000 CFU/g in chickens had decreased since 2014 but it remained high in smaller retailers, independent shops and butchers.

Data from April to June shows 12.1 percent of birds were positive in the 100 to 1,000 CFU/g category compared to 15.8 percent in the last quarter, 11.4 percent from October to December 2018, 11 percent from July to September and 12.5 percent from April to June.

The CFU/g 10-99 category had the same rate of positive chickens as the January to March period at 25.3 percent. This compared to 22.3 percent in October to December 2018, 26.7 percent in July to September and 23.3 percent in April to June.

In the lowest category, CFU/g less than 10, 59 percent of chickens were positive, versus 55.4 percent in the last set of results, 63.1 percent from October to December 2018, 58.8 percent from July to September and 60.6 percent in April to June.

Findings by retailer

Marks and Spencer recorded 3 percent in the top category in April and 2 percent in May and June based on a sample of 388 M&S chickens. The retailer recorded 6 percent in the highest category in January and 2 percent in both February and March based on samples from 278 chickens.

Tesco data showed the percentage at this level dropped to 5 percent from 439 samples versus previous results of 6 percent positive at the top category based on 362 samples.

Aldi results for April to June show that 4.2 percent of birds were in the more than 1,000 CFU/g category compared to 5 percent in the previous quarter. Asda reported 4.7 percent in this bracket which was lower than the 5.5 percent figure from January to March.

Co-op had 1.8 percent of chickens sampled contaminated at greater than 1,000 CFU/g which is double the number from the last quarter. Lidl recorded just below 2 percent which was up slightly from 1.5 percent in Q1 2019.

Morrison’s results found 3.5 percent of chickens had higher levels of contamination from a sample of 115 chickens. From January to March the supermarket had 5.4 percent of 111 chickens with the highest level of contamination. Sainsbury’s results increased to 3 percent of chicken samples at the highest level compared to 1 percent in the last quarter.

For the second quarter of the year, 6 percent of Waitrose and partners chickens tested positive for Campylobacter at more than 1,000 CFU/g compared to 2 percent in the previous results.

A Waitrose and partners spokesperson said it had surveyed chicken at the factory and on supermarket shelves.

“Our testing regime is rigorous and because we know the prevalence of Campylobacter is reduced over a product’s shelf life we have ensured our sampling is random and adhered to the FSA testing protocol throughout the survey. These results demonstrate the robustness of our testing procedures and we are confident that our approach to tackling Campylobacter is consistently effective.”

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