Department of Health

Health warning on blue-green algae

Health advisory

Status:
Active
Advisory number:
220527
Date issued:
26 May 2022
Issued by:
Angie Bone, Deputy Chief Health Officer (Environment)
Issued to:
Consumers and health professionals

Key messages

  • A harmful blue-green algal bloom is occurring in the Gippsland Lakes and along the Ninety Mile Beach, near Lakes Entrance.
  • Some species of blue-green algae produce toxins which are harmful to human health.
  • Direct contact with the toxins can cause local irritation to the skin, eyes, ears, nose and mouth.
  • Do not swim in algal blooms or come into contact with affected water.
  • Accidentally swallowing algae-affected water or consuming seafood containing toxins can lead to illness.
  • High levels of toxins have been detected in seafood caught within the Gippsland Lakes, and more recently in prawns caught off the coast of Lakes Entrance.
  • Do not consume potentially affected seafood.

What is the issue?

A harmful blue-green algae (cyanobacteria) bloom has been occurring in the Gippsland Lakes since February 2022. The bloom has now spread into the ocean along the Ninety Mile Beach with movement being influenced by the weather and tidal system. This species of algae cannot survive in the ocean and is actively breaking down due to the saltwater. This bloom has gone on longer than expected and it is unknown how long the bloom will be in the area.

Toxins produced by harmful algal blooms can impact human and animal health. The species of algae causing the bloom is Nodularia spumigena, which produces the toxin nodularin. The toxin concentrates in shellfish, and the internal organs of fish. Any affected seafood should not be consumed. Toxin levels can remain elevated in seafood for several weeks to months after an algal bloom has disintegrated.

High levels of toxin have been detected in seafood caught within the Gippsland Lakes, and more recently in prawns caught off the coast of Lakes Entrance.

Health impacts of harmful algae

Direct skin contact with harmful algae can cause skin and eye irritation.

Inhalation of fine spray or droplets of algae-affected water during recreational activities such as water-skiing can cause mild respiratory effects and symptoms similar to hay fever.

Accidental swallowing of algae-affected water or consuming seafood containing toxin can lead to gastroenteritis with vomiting, diarrhoea and abdominal pain. Ingestion of high levels of toxins can affect the liver and cause serious illness.

If you are concerned for your health, consult your GP immediately.

Pets and livestock can also be affected by harmful algae. Animal deaths have occurred. If you think that your animals are unwell, consult your vet.

Who is at risk?

Anyone who is exposed directly to blue-green algae through:

  • direct contact with exposed parts of the body, including sensitive areas such as the ears, eyes, mouth, nose and throat
  • accidental swallowing of affected water (e.g. during swimming)
  • breathing in water droplets and aerosols (e.g. during water skiing); and
  • consuming affected seafood.

Anyone who consumes shellfish or crustaceans caught inside the Gippsland Lakes is at risk of illness. Advice and warnings have been in place at the Gippsland Lakes since February 2022. There is some risk that prawns, crabs, bugs and pilchards caught from outside Lakes Entrance since 1 April 2022 contain nodularin toxin in excess of health guideline values.

The Department of Health is not aware of any cases of human illness from consumption of seafood affected by the current Gippsland Lakes algal bloom.

Recommendations

The following advice may be updated based on monitoring underway by relevant government departments. For the most up to date information go to the Vic Emergency website.

For the public

Advice for contact with water

Humans and animals including pets should avoid contact with water at all parts of Lake King, Lake Victoria and where algae are visible along Ninety Mile Beach from McLoughlins Beach to Marlo. Avoid contact with any area of water that appears discoloured, murky or has evidence of scum. Follow advice on any harmful algae information signs present and avoid contact with the water until authorities advise there is no longer a risk.

If you have contact with affected water, immediately leave the water. Remove any traces of algae by thoroughly washing and rinsing your skin and hair, and by putting contaminated clothes and wetsuits in clean water. Wash and dry all clothing and equipment. Use of wetsuits for water sports may increase the risk of rashes, because algal material in the water trapped inside the wetsuit will be in contact with the skin for long periods.

If you feel ill after contact, seek medical advice and contact your GP immediately.

Advice for consumption of seafood

Advice for recreational fishing is in place for all of the Gippsland Lakes and the Ninety Mile Beach from McLoughlin’s Beach to Marlo. Do not consume crustaceans (including prawns, crabs, bugs), shellfish or pilchards harvested from this area.

Fish caught from this area should be washed thoroughly and gutted and gilled prior to cooking or freezing. Do not eat whole fish harvested from algae-affected waters. If you see fish that are dead, dying or swimming erratically, do not touch or eat them.

In addition, advice has been issued to not consume prawns harvested from McLoughlin’s Beach, southwest of Lakes Entrance, to the Victoria - New South Wales border.

If you have eaten seafood harvested from the southeast coast of Victoria and are well, you do not need to do anything. If you have purchased prawns, crabs, bugs or pilchards harvested since 1 April this year from the southeast coast of Victoria and still have some left, you should dispose of them. If you are unsure where your seafood was harvested, contact the place of purchase.

Freezing or cooking the seafood does not destroy the toxins.

If you are experiencing symptoms after consuming potentially affected seafood, seek medical advice from your GP immediately.

For health professionals

Clinicians should be aware of compatible clinical presentation in people who have recently consumed prawns, crabs, bugs or pilchards caught within the Gippsland Lakes since the bloom commenced or outside Lakes Entrance since 1 April 2022.

Clinicians should continue to notify two or more related cases of suspected food or water-borne illness (including from toxin affected seafood) to the Department of Health by calling 1300 651 160 (24/7).

Reviewed 27 May 2022

Health.vic

Contact details

Food safety unit Department of Health

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