Brian Jones

On 17 February 2017 I advised the Hon. Barnaby Joyce, Minister for Agriculture and Water Resources, of my intention to review: • circumstances leading to the 6 January 2017 suspension of uncooked prawn imports into Australia, and • biosecurity considerations relevant to future trade in uncooked prawns. The suspension followed initial investigations into the source of an outbreak of the previously exotic white spot disease (WSD) in prawn farms and wild crustacean populations near the Logan River, in south-east Queensland. WSD is caused by white spot syndrome virus (WSSV) infection of crustaceans. It is not of concern to human health. However, it is one of the most severe diseases of farmed prawns, especially the valuable black tiger prawn Penaeus monodon farmed in Australia. WSD can kill up to 100 per cent of prawns in a pond within two to five days of the first signs of disease. Since its emergence in China in 1992, WSSV has become endemic in all countries with prawn aquaculture industries, except New Caledonia and Australia, costing at least US$1 billion a year. On 21 March 2017 the Senate, through its Rural and Regional Affairs and Transport References Committee, finalised terms of reference of an inquiry into ‘Biosecurity risks associated with the importation of seafood and seafood products (including uncooked prawns and uncooked prawn meat) into Australia’. The committee held public hearings and published its final report on 31 October 2017. On 6 July 2017 the suspension of uncooked prawn imports lapsed. By this time, the Director of Biosecurity had put in place alternative import conditions for selected prawn products from specified countries. Implementation was underway when this report was being prepared. Public submissions to both my review and the Senate inquiry have been published. The information summarised in my report is drawn from these documents and from the findings of my field work and internal inquiries at the Department of Agriculture and Water Resources.

Perkinsus is the widespread cause of disease and lost production in mollusc fisheries world - wide. Found mostly in temperate waters, two species are listed internationally as notifiable by the OIE and also appear on Australia's National List of Reportable Diseases of Aquatic Animals. Although Perkinsus marinus is exotic to Australia, Perkinsus olseni is enzootic and well - known as the cause of serious infections in various wild abalone populations in south - eastern Australia. The rapid identification and reliable differentiation of species is a major issue in the diagnosis and management of Perkinsosis in Australia. Traditional methods of Perkinsus diagnosis, such as histology and Ray’s thioglycollate culture, are straightforward and practical, however they lack sensitivity and fail to differentiate specific species. The molecular methods currently recommended by the OIE are based on conventional 1 - step PCR which is generally more labour intensive, slower and less sensitive than real - time PCR. The primary aim of this project was to develop and validate a species - specific real - time PCR (qPCR) assay for Perkinsus olseni

This project used DNA-based technology to study the effects of environmental stress on pearl oysters. During the oyster farming process, oysters are subjected to a range of changes in their environment, such as fluctuating temperature and salinity. These changes are exacerbated by farming practices, during which oysters are exposed to additional stresses, such as routine antifouling and nucleation. All of these factors have the potential to stress oysters, potentially affecting their growth, susceptibility to disease and other important characteristics that decrease productivity. At its most basic level, stress causes changes in the activity of genes in oysters, switching some on and turning others off. It is these changes in gene activity that alter characteristics such as growth rate and susceptibility to disease…

The virus that causes Abalone Viral Ganglioneuritis (AVG) is considered to be exotic to Western Australia (WA). The known distribution includes Victoria, Tasmania and Taiwan. There are a number of known strains of the virus; Tasmanian strains do not (to date) cause mortalities in wild abalone (but do so in farms and processing facilities). Victorian and Taiwanese strains cause high mortalities in wild abalone. Despite active surveillance, the virus has not been found in NSW, South Australia or Western Australia but there is a low likelihood that WA specific strains may exist undetected. The risk posed by AVG virus occurring in juveniles sourced from hatcheries in WA and translocated to the open ocean in southern Western Australia either for stock enhancement (reseeding) or for marine grow-out (sea-ranching) purposes has been assessed using standard risk assessment methodology with the outputs having been independently reviewed. While the likelihoods of the AVG virus occurring in the hatchery range from “negligible to “low” should no additional management measures be applied, the consequences of detection (including biological, economic and environmental) are generally “High” and in two cases the resultant risks were “unacceptable” with just the current legal management requirements. Given that the initial risks associated with oceanic deployment of abalone were assessed as Moderate to High, additional formal management intervention is required to reduce these to acceptable levels. The primary concern is that the virus could become established in a hatchery facility and then be more likely to infect wild stock through the release of hatchery released juveniles into the oceanic waters. The likelihood of this outcome occurring has been assessed as very low if the suggested hatchery management measures that could be applied to mitigate the risk to an acceptable level are adopted. Protocols are in place to ensure that any emergence of AVG in a hatchery would be detected. If the virus was ever detected in the hatchery the water supply should be immediately shut down. This can be done using existing legislation (FRMA r177(2) so there is no legislative impediment to limiting effects of a disease outbreak in a hatchery). The placement of grow out structures and juvenile releases could also be planned in a manner to both minimise the likelihood of transmission to wild stocks and limit the spread of any infection.

Biosecurity Australia commissioned a program of testing of goldfish, cichlids, gouramis and livebearers in quarantine. These species were identified as high risk in the 1999 Import Risk Analysis on Live Ornamental Finfish. In the program reported on here, these species were targeted for diagnostic testing when more than 25% of fish in a quarantine tank died during the quarantine period. Diagnostic testing usually involved post mortem, histology and bacteriology with provision for further confirmatory diagnosis as required. Participating diagnostic laboratories in Queensland, New South Wales, South Australia and Victoria were provided with details of basic disease testing procedures and requirements to ensure a consistent approach across all states. Procedures were agreed with AQIS and established nationally to supply targeted fish to the testing laboratories. One hundred cases were investigated from the five states. Victoria ha d the most submissions (43), followed by Queensland with 29 and Western Australia with 15. A bacterial cause was diagnosed in 26 cases and in 13 of these cases the bacterium was Aeromonas hydrophila or Aeromonas sp. 41 diagnoses of protistan and metazoan parasites were made and of these the greatest number were Monogenea (14 cases). There were eight reports of fungal involvement including seven cases of epizootic ulcerative syndrome (EUS). Viral aetiologies were listed in seven submissions. These included four cases of iridovirus in cichlids and one of haematopoietic necrosis virus in goldfish (GFHNV). Stress was reported as a contributing factor in at least 11 submissions. The large number of diagnoses of EUS, all in gouramis, and the four cases of iridovirus in cichlids is of concern. Surprisingly iridovirus was not diagnosed in gouramis during the survey despite most previous diagnoses of this virus in ornamental fish in Australia being in gouramis