Aeromonas salmonicida subsp. salmonicida

This disease is a trout fisher's nightmare. It can kill a trout or salmon in a matter of days.

About furunculosis

This bacterial disease causes boil-like lesions and bleeding in salmon and trout.

Why this is a problem for New Zealand

If furunculosis came to New Zealand, all our salmon and trout species would be vulnerable to this disease. It can kill an infected fish in 2 to 5 days. Outbreaks happen when water temperatures are above 10°C.

The bacteria can survive for several months outside its fish host in both marine and freshwater. This makes the bacteria extremely difficult to eradicate and can result in new infections.

How it could get here

Live, freshly caught fish is the most likely way for this disease to reach our shores. However, we have very strict controls in place for importing fish to New Zealand.

If you catch a trout or salmon that has large boils or looks unhealthy

  • photograph it
  • place it in a plastic bag and refrigerate
  • call 0800 80 99 66

Note, diagnosing fish diseases requires laboratory testing. Signs of fish diseases are difficult to tell apart.

Note: This information is a summary of this disease's potential impacts on New Zealand.

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