Blue Green Algae Poisoning in Dogs

Overview
- Blue green algae is a bacteria, most commonly found in stagnant water, such as ponds, streams and lakes.
- Blue green algae can be very dangerous because it produces invisible, toxins that can cause organ damage and sometimes even death.
- Blue green algae can be very tricky to spot, so it’s important to know what to look out for before letting your dog near any water that might contain it.
- Blue green algae grows best in warm weather, so poisonings are most common between late spring and autumn.
- Contact your vet ASAP if you think your dog has been exposed to blue green algae.
Why is blue green algae dangerous?
Blue green algae (or ‘cyanobacteria’), is a type of bacteria, most commonly found in stagnant water. It’s called ‘algae’ because it often forms a green scum on the surface of water. Not all types of blue green algae are dangerous, but some produce toxins that spread throughout the water and if swallowed, can cause organ damage and potentially death. Your dog is at risk of blue green algae poisoning if they swim in, or drink contaminated water. Blue green algae can be difficult to spot, and its toxins can’t be seen by the naked eye, so it’s very important to know what to look out for before allowing your dog to swim.
Symptoms
Symptoms of blue green algae poisoning can take anything from 15 minutes to a few days to develop. Symptoms are often vague and include:
- Vomiting (sometimes with blood)
- Twitching
- Seizures
- Increased thirst
- Drooling
- Diarrhoea
- Breathing difficulties
- Collapse
- Sudden/unexplained death.
Treatment
First aid. If your dog comes into contact with blue green algae, don’t allow them to lick their fur, wash them (if possible) and call your vet ASAP. The more toxins your dog takes in, the worse their poisoning will be.
There is no specific treatment available, so your vet will treat your dog’s symptoms, support their organs and try to prevent the toxins causing any further damage.
Toxin removal. Your vet is likely to make your dog vomit and give them a charcoal meal to remove/absorb any toxins already inside them. It’s likely that they will also wash your dog, to remove any toxins from their fur.
Intensive care. If your dog has developed symptoms of poisoning, they are likely to need intensive care, which may include a fluid drip, medicines, close monitoring and blood tests.
Sadly, even with the best care, some dogs die from blue green algae poisoning.
Consider insuring your dog as soon as you get them, before any signs of illness start. This will ensure you have all the support you need to care for them. When starting an insurance policy, always check the level of cover you are paying for.
How to avoid blue green algae poisoning
- Check the water before allowing your dog to swim, even if it’s somewhere you’ve been before.
- Be very careful around stagnant water such as ponds and flooded fields, especially in the summer and autumn.
- Always carry water for your dog to drink instead of letting them drink from open water.
- When travelling, check local council websites, and look out for warning signs around ponds, lakes or rivers.
- If you think you’ve found blue green algae, report it to the Environment Agency or local council who can test the water and put up signs to keep everyone safe.
Fortunately, blue green algae is uncommon and not all types are toxic. However, it’s impossible to tell which types are/aren’t toxic just by looking, so if you’re unsure, don’t let your dog near the water and take them somewhere else to swim.
FAQ’s
Can people get blue green algae poisoning?
Yes, blue green algae toxins can affect humans too. If you or someone you know has come into contact with blue green algae, contact your doctor or the NHS for advice.
Can other pets get blue green algae poisoning?
Yes, sadly many animals can get blue green algae poisoning included cats, horses and fish. If you’re concerned your pet has blue green algae poisoning, contact your vet ASAP.
Published: July 2020
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Written by vets and vet nurses. This advice is for UK pets only.
Illustrations by Samantha Elmhurst