Student exposes bugs in chicken

Jane Millar's discovery, as a 17-year-old St Margaret's College student, is being compared with the two schoolgirls who rumbled the makers of Ribena over false claims about vitamin C levels.

Millar's findings of a range of resistant bacteria in chickens that could compromise antibiotic treatment in humans are expected to cause similar waves in medical circles.

The key finding was that the bacteria have developed resistance to antibiotics not used in the poultry industry but important for treating serious infections in humans.

Scientists are calling for further investigation and the discovery is about to be published in the New Zealand Institute of Medical Laboratory Science's journal.

Millar's chicken experiment began as part of an International Baccalaurette Diploma during her Year 13 last year.

She bought six fresh chickens - free-range, barn-raised and organic - from a Christchurch supermarket. She took samples from each bird and grew bug colonies, which she used to test different antibiotics.

Apramycin is an antibiotic used sparingly by the New Zealand poultry industry to treat infections.

The bacteria of two chickens tested resistant to apramycin. They also proved resistant to another two antibiotics from the same family - gentamicin and tobramycin - used for serious human infections.

Gentamicin is not used by the poultry industry; tobramycin is restricted to human use only.

"The main finding is that we can create resistance to medically important antibiotics by using antibiotics that are presumably safe in agriculture," Millar said.

Resistant bacteria such as those found in the chicken could live in the human intestinal tract and easily transfer their resistances to other bugs, she said. This process produced superbugs in humans that were hard to treat, resulting in prolonged illness and a greater risk of death.

Millar's mentor, John Aitken, a medical laboratory scientist from Southern Community Laboratories, was surprised that the range of resistance showed up in such a small sample.

"What Jane has done is taken a very small snapshot and it has shown a surprising observation," he said. "But it's a time-specific snapshot and it's not a good look."

Poultry Industry Association executive director Michael Brooks said the use of antibiotics in chickens was heavily regulated.

"The industry works closely with the New Zealand Food Safety Authority (NZFSA) to ensure the safety of all poultry products," he said.

Brooks commended Millar on her work and said the association had provided her with data on the industry.

Millar believes the use of apramycin should be halted until a larger study is done on its consequences.

"You need to do a big investigation and find out how much apramycin is being used now and what kind of resistances are coming out," she said.

- © Fairfax NZ News