VIBRIO OUTBREAKS IN SHELLFISH

Vibrio outbreaks in shellfish. New Zealand Seafood Safety researchers have been working to identify knowledge gaps needed to understand what factors trigger vibrio outbreaks.

In the past two years there have been reported Vibrio parahaemolyticus illnesses associated with consumption of raw or partially cooked mussels harvested from the Coromandel in the early winter season. These outbreaks were the first to occur in New Zealand for many decades and have put the shellfish industry, Ministry for Primary Industries (MPI) and scientists on alert.

Plant & Food Research, who are part of the New Zealand Seafood Safety platform led by Cawthron Institute, have established methods for Vibrio parahaemolyticus detection, strain determination, identification of seasonal risk periods and pathogenicity markers. However, knowledge gaps remain as there is a lack of understanding regarding what factors trigger the presence of pathogenic strains within shellfish growing areas.

To help safeguard New Zealand’s shellfish industry, members of the New Zealand Seafood Safety platform along with industry representatives, MPI, and international experts gathered at a workshop held by Cawthron in December 2020. They discussed the recent Vibrio parahaemolyticus illness outbreaks and identified research gaps and science needs. While Vibrio does not pose an immediate threat to most industry operators, there is potential for the threat to increase in the future as climate change drives a rise in sea temperature.

The workshop helped participants to gain a greater understanding of the Vibrio bacteria in the marine environment. Presentations from scientists based in the UK and Canada provided an international context and experiences from their respective regions. The group explored research options to better understand what drives Vibrio pathogenicity and to help with future outbreak responses. The group will now scope the required research and determine how this will be supported. What is clear is that it will require collaboration and partnership between Seafood Safety Platform scientists, shellfish industry representatives and MPI.

The workshop participants said they would like to thank Dr Andy Powell from Cefas in the UK and Dr Enrico Buenaventura from Health Canada for their involvement in the workshop and online presentations.

Source: Cawthron Institute