Cyanobacteria, also known as ‘blue-green algae’, can multiply in stagnant or shallow water during the warm months (summer – autumn).

These organisms can release toxins that are dangerous to animals, dogs in particular, when they drink or swim in contaminated water.

How do you recognise them?

  • Floating mats that look like wet wool
  • Unusual water colour: turquoise-green, reddish, yellow-brown

Possible signs of poisoning in your pet:

  • Vomiting
  • Diarrhoea
  • Sudden weakness, convulsions
  • Neurological signs

Our prevention advice:

  • Never let your dog drink from or bathe in suspicious water
  • Avoid areas with floating scum or discoloured water
  • Rinse your pet with clean water after any contact
  • See a vet immediately if in doubt

If you suspect contact or see symptoms:

  • Call the AuFuret Veterinary Practice in Échichens: +41 21 811 55 11
  • Or the medical on-call centre (Centrale des urgences médicales): 0848 133 133

Report serious cases:

  • Directorate General for the Environment (DGE, canton of Vaud): 021 316 43 60 | info.dge@vd.ch
  • Veterinary Affairs Directorate (canton of Vaud): 079 830 17 58

👉 For more information, see the official website of the veterinary office of the canton of Vaud or our news page.