Prawn Farm Disease Response Policy Drafting a plan to improve disease management together - Progress and issues for improvement

Why we need a Policy Aim: Industry and Government agreement on what is required Improved co-operation Allows appropriate preparations for all involved Better, faster decision-making, consider all input Training Resource prioritisation, eg diagnostics, field staff

Penaeus Monodon Mortality Syndrome March 2015 Cardwell. Similar to AHPND but: different bacteria (Vibrio harveyi, not v. parahaemolyticus). Still free-living Toxin genes do not appear to be in a plasmid 6-8 weeks post stocking (AHPND normally within 4 weeks) NT broodstock, but this does not appear to be the source 70-100% mortality Since then subsequent detections mostly in older prawns (eg 15 weeks) but not widespread Normal Pale & abnormal

Penaeus Monodon Mortality Syndrome Jan 2016 Bundaberg 3 farms 35 - 100 days old Another different bacteria (Vibrio sp) Toxin genes appear to be in a plasmid Separate origin to Cardwell

Penaeus Monodon Mortality Syndrome PMMS pathology is new to BQ pathologists, which means: emerging; or introduced; or was present but not reported / discovered International notification as hepatopancreatitis.

Elements of disease response Notification / contact lab – free advice from experts On-farm biosecurity plan to minimise risk of spread Sampling and diagnosis Define extent Destroy the pathogen Emergency harvest/destruction, disposal, disinfection Testing to demonstrate freedom

Decision points What is the objective? 3 Choices Eradication Containment control and zoning Management and mitigation Need to decide with whatever evidence is available

Decision points Stock isolation, destruction and disinfection How much evidence do we need? Is it feasible on a large scale? What triggers whole-farm isolation/ eradication? Net harvest vs drain harvest Are we better to get them out ASAP? Risk of spread via predators vs spread in water Risk depends on situation – eg settlement pond, netting, size of prawns

How should we approach this disease? Key evidence so far: Treat as new / emerging disease – no evidence of incursion Not AHPND- but almost. Name does not change our response Causal effect still not established - precautionary approach Origin is unknown Environmental source is likely - eradication very unlikely Probably not widespread at this stage Significant potential to damage industry

How should we approach this disease? Proposed aim: Containment, control and zoning Positive diagnosis = immediate tracing and risk assessment Emergency (net) harvest or destruction of all suspect ponds Cease discharge from suspect and high risk ponds Movement controls activated BQ will support and ensure compliance

How should we approach this disease? Rapidly define spread of pathogen Test 30 prawns (assuming 10% prevalence) for toxin genes only from each ‘high risk’ pond If evidence of significant spread- whole farm is treated as infected Proof of freedom before movement of live or fresh prawns

To make this more effective… Government has identified a need for training Biosecurity officers / BQ vets/ Fisheries will cover aquaculture response Queensland Biosecurity Capability Review Joint industry-government taskforce? Eg disinfection protocol Other expertise/ resources? EADRA will help spread the financial risk and strengthen industry involvement

Thanks and good luck this season! Tim.Lucas@daf.qld.gov.au Phone: 0491 226 436 Lab: 32766062 bslclo@daf.qld.gov.au