Foodborne listeriosis is caused by the bacteria Listeria monocytogenes. Although the number of human cases in New Zealand is small (approximately 20-40 notified cases per year), clinical outcomes are serious and severe, including mortality in the very young (including foetuses) and the elderly. The effect on food businesses can also be severe. For example, a New Zealand outbreak linking ready-to-eat meats with four cases including two deaths in 2012, resulted in the producer being prosecuted and fined approximately $200,000.
The New Zealand Food Safety Science and Research Centre (NZFSSRC(external link)) is a collaboration of seven partners; three Crown Research Institutes, including ESR and three universities and a private research organisation. The Centre has a research programme focused on food safety risk management of Listeria. Within this programme, ESR currently leads a project that is collating and analysing whole genome sequence data from a range of Listeria isolates from food, water, livestock, the environment, as well as clinical isolates from human cases of listeriosis. Collation of this large dataset allows us to look more closely into the Listeria population structure within New Zealand and put it into an international context. This enables us to gain insight into the evolution of this pathogen in New Zealand and identify the appearance of new strains and assess their ability to cause human disease (virulence).
The genomic data has been incorporated into a database with a user-friendly dashboard that NZFSSRC members including industry can access. The dashboard enables a user to compare Listeria isolates of interest.
The Listeria genomes can also be mined further to identify new targets for Listeria control in order to prevent persistence in food processing environments. This programme will not only provide information to the New Zealand food industry but will also help to protect New Zealand’s public health.
Read the article by NZFSSRC [PDF, 9.6 MB] about the Listeria programme.