On Tuesday the Food Standards Agency published the first set of results from quarterly testing carried out on shop-bought fresh chickens in the UK.

The tests found food poisoning bug Campylobacter on 59 percent of chickens. Samples were taken from chickens' neck flaps. In 4 percent of cases, Campylobacter was also found on the outside of the packaging.

Although Campylobacter is killed by thorough cooking, the bacteria remain the most common cause of food poisoning in the country, so the findings are worrying. Even so, they are in line with the results of previous investigations into the presence of the bacteria, which have also found Campylobacter in around two-thirds of raw poultry samples.

An estimated 280,000 people a year suffer from food poisoning caused by the bacteria in the UK alone and the majority of these cases can be linked back to contaminated poultry.

The FSA tests were part of a 12-month survey, begun in February 2014, to examine the extent of Campylobacter contamination in fresh chilled chickens on sale in the UK. In all, 4,000 samples will be taken over the course of the year; samples have been taken from supermarkets, as well as smaller independent retailers and butchers. Tuesday's results are based on 853 samples taken between February and April.

Catherine Brown, FSA Chief Executive, commented on the findings, "This survey… will give us a clearer picture of the prevalence of Campylobacter on raw poultry sold at retail and help us measure the impact of interventions introduced by producers, processers, and retailers to reduce contamination.

"The chicken supply chain is looking at how interventions such as improved biosecurity on farms, rapid surface chilling, and anti-microbial washes can help reduce Campylobacter. So when they take action and invest in interventions designed to make a difference, these survey figures will enable us to see if they really do make an impact."

Brown added that "There is still a lot more to be done by all elements of the supply chain to ensure that consumers can be confident in the food they buy."

The FSA chief executive said the Agency will publish data comparing the prevalence of campylobacter between different retailers as soon as it is available.