Identifying campylobacter: from poultry to petrie dish and back again.

September 2007
Veterinary public health research at Massey has expanded to new dimensions of diagnostic capability with its relocation to the new Hopkirk Research Institute.

Professor Nigel Frenchs multi-disciplinary team is studying the genes that campylobacter carries to try and develop new ways of tracking the pathogens. This project to identify and predict the occurrence of food poisoning threats in New Zealand and devise strategies to minimise their effect, is one of the largest underway in the Hopkirk. Funded mainly by the New Zealand Food Safety Authority, the collaborative research could ultimately lead to the development of novel ways of controlling campylobacter.

The team of scientists was one of the first from Massey's Institute of Veterinary Animal and Biomedical Science (IVABS) and AgResearch to move into the new centre. Dr French says that even though they have only been there a short time, working in the state-of-the-art facility combined with the ability to collaborate with other researchers, has already made a huge difference to their research on pathogens transmitted from animals to humans- particularly campylobacter.

Dr French says the advanced laboratories in the new institute allow his team to further their research, taking it into the rapidly growing field of molecular epidemiology, which focuses on identifying the source of infections.

In these first collaborative projects, we will look at these pathogens at the genome level, identifying markers that may explain why some strains are responsible for causing disease in humans, whereas others are less important as human pathogens, he says.

Working with two AgResearch colleagues, Dr Grant Hotter (Infectious Diseases Molecular Biology team) and Dr Bryce Buddle (Infectious Diseases Immunology team), Prof. French says his team are already investigating more sophisticated methods of typing the pathogens so they can be better sourced and tracked, as well as building better understanding of immunity and host responses to the pathogens.

A comprehensive library of New Zealand-specific strains of campylobacter jejuni (built up by Nigel over several years), will mean a greater comparative study is possible which will be critical in reducing human exposure to the pathogen and developing new therapies and vaccines.

Campylobacter levels soaring

Campylobacter is one of several infectious diseases transmitted between animals and humans that significantly threaten the health of New Zealanders. Levels are increasing annually - 2006 was the worst year on record.

Fresh chickens cop most of the blame for campylobacter infections, and in fact they are estimated to be the source of at least 50% of infections as the pathogens are carried very effectively in their guts. As well as their lab work which includes sampling meat bought from retail outlets, Prof. Frenchs team have been working with the poultry industry researching ways to reduce the contamination of food from poultry plants including the reduction of contamination in slaughterhouses.

Chicken not the only culprit

Current evidence suggests that more cases of campylobacter are coming from ruminant sources than was initially thought, and it is likely that these infections are picked up from both food (e.g. red meat) and the environment. Prof Frenchs team is also carrying out research on red meat sources of the pathogens and conducting environmental water testing of Manawatu swimming holes for pathogens potentially coming from run-off into waterways. Later in the year, Dr Frenchs team will be working with a Cross Departmental Research Programme (including the Ministry for the Environment, NZFSA, NIWA and ESR) investigating environmental factors.