A new survey revealing that Campylobacter was detected in 65 percent of retail chicken samples in New Zealand has caused something of a storm in local and social media.
Consumer NZ chief executive, Sue Chetwin, has said that 26 of the 40 fresh chicken products obtained from supermarkets tested positive for the bacteria, which are the leading cause of gastrointestinal infections officially recorded in New Zealand.
Fresh chicken is considered responsible for half of all cases of campylobacteriosis, according to Chetwin. The consumer association used the results to repeat its call for official Campylobacter testing to be carried out at retail outlets as well as poultry processing plants.
“The bug’s presence in the products we tested doesn’t mean you’ll get sick from the chicken but it increases the chances,” she said.
Poultry producers’ reaction to the survey
New Zealand is entering the summer, which is the peak period for cases of food poisoning linked to Campylobacter.
Chicken accounts for 40 percent of campylobacteriosis cases in New Zealand, according to the Poultry Industry Association (PIANZ), and the number of people with the illness had been trending downwards for a several years - until a major outbreak linked to contamination of the water supply at Havelock North earlier this year.
PIANZ director, Michael Brooks, told Stuff that the latest study used a different test procedure from the official method proscribed by the Ministry for Primary Industries (MPI).
“The consumer test was on a select piece of chicken with highly sensitized testing to pick up the smallest trace of Campylobacter,” Brooks said.
Progress in reducing campylobacteriosis
In New Zealand, campylobacteriosis rates began to rise in the mid-1980s and peaked in 2006 with 15,873 notified cases, according to a 2011 report from the University of Otago in Wellington, where the Department of Public Health has been involved in tackling the “epidemic.” With 384 cases per 100,000 population, New Zealand had the highest rate reported internationally for this disease in 2006.
However, since the New Zealand Food Safety Authority – now part of the Ministry for Primary Industries (MPI) - and the poultry industry introduced a range of regulatory and voluntary measures in 2007 aimed at reducing levels of Campylobacter on fresh chicken meat, rates have declined significantly.
“This decline in Campylobacter infection is one of the largest drops in disease incidence ever recorded for a national epidemic of this type,” said then-Associate Professor Michael Baker.
Interventions that successfully reduced chicken contamination in New Zealand included setting mandatory targets for producers to reduce Campylobacter contamination of chicken meat, better hygiene practices during chicken processing, and changes to the chilling process.
Rates of infection have continued to reduce over the last decade. According to Chetwin of Consumer NZ, around 135 per 100,000 New Zealanders fell ill with campylobacteriosis in 2015.
One year ago, MPI deputy director-general, Scott Gallagher, told Radio NZ that the country’s food safety system was robust, and protected people from Campylobacter and other hazards, and that the ministry was not considering any additional measures.
However, PIANZ backed a call from Professor Baker for the regulated limit on Campylobacter levels in chicken to be reduced to a much lower level.
“We can lower the regulatory limit of Campylobacter on fresh poultry,” Baker said. “This was introduced seven to eight years ago and when it was done, it resulted in a halving of our disease rate. We think that the regulatory limit needs to be dropped to a much lower level. And that would virtually turn off this epidemic overnight.”
In April of 2016, MPI published an amendment to the law on Animal Products (National Microbiological Database Specifications). This focused on reporting by broiler chicken processors whose recorded levels of Campylobacter exceed prevalence targets for a three-month period.