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Blue Green Algae Awareness

Have you heard of Blue Green Algae? In this blog, we’re going to explore one of the nastiest “natural” toxins your pet is ever likely to come into contact with. What it is, what it does, and what we can do to help…

So, what do you know about Blue-Green Algae? Are you prepared…?

What are Blue Green Algae?

Well, if you answered that they were algae that are bluish green in colour… you’re half right, but only half. They’re actually a family of bacteria called Cyanobacteria (because, of course, of their characteristic colour). They like to grow in still water that’s rich with nutrients, so are most commonly found in ponds and smaller lakes, although larger waterways may occasionally be affected as well. Most of the time, the numbers in a given waterway are low enough that poisoning is very unlikely; however, occasionally the conditions are “just right” for an Algal Bloom to occur.

What can trigger these Algal Blooms, and how can we recognise them?

Typically, a prolonged spell of warm, sunny weather, as the sunlight and warmth allow the bacteria to multiply, and at the same time, the water levels tend to fall making them more concentrated. The individual free-floating bacteria are invisible to the naked eye; however, they often cluster together in clumps, flakes or clusters which we can see. These aggregations, or clusters, are typically blue-green or greenish in colour, although occasionally they may be brown.

More commonly, however, a serious algal bloom is visible as blue-greenish or brown scum on the surface, or perhaps as a foamy material around the edges of the pond.

What makes them dangerous?

There are many, many different species of Cyanobacteria. Some of them are harmless; and of the others, most are very, very variable in how much toxin they produce - or indeed if they are producing any at all. As a result, it is impossible to know just by looking whether an algal bloom is of a harmless strain, or a lethal one. We therefore recommend treating them all as dangerous, and allowing the Environmental Agency to do the complex laboratory research needed to determine which is which!

The dangerous ones produce two types of toxin, which have 2 different types of effects. Some produce neurotoxins, that affect the brain and nervous system leading to paralysis and potentially death from suffocation; others produce hepatotoxins, that damage the liver. Sadly, there are also blooms that produce both at the same time. Dogs who swim or drink from stagnant ponds are at the highest risk, as they are not only more likely to be exposed, but they are also more susceptible to the toxins than some other animals. That said, cat poisonings from Blue Green Algae exposure have been recorded, as have poisonings in farm animals and birds, as well as people (especially children). The toxins are really nasty, so be cautious!

What are the symptoms of poisoning?

To some extent, of course, it depends on the type of toxin.

Neurotoxin exposure may lead to symptoms in as little as a few minutes, typically muscle tremors and disorientation. This may, if enough has been absorbed, progress to muscle weakness, collapse, difficulty breathing, coma and ultimately death. Occasionally, other neurological signs like convulsions or seizures may occur, depending on exactly which of the neurotoxins the bloom is making.

Hepatotoxin poisoning is more slowly acting, taking 1 to 4 hours before symptoms appear. In these cases, the initial signs tend to be vomiting and watery diarrhoea, that may become bloody. As liver failure progresses, jaundice, abnormal behaviour, unusual bleeding, seizures and collapse may occur, and in many cases, death follows in a few days.

Can it be treated?

There is no specific antidote to most of the toxins; however, our first response will usually be to induce vomiting or pump the stomach to get rid of any more toxin before it’s been absorbed). Using activated charcoal may also slow down absorption from the gut. Once that’s done, we’d want to admit the dog for intensive care nursing - intravenous fluids (a drip), oxygen and medications to flush the kidneys and support the liver, and control any symptoms. Unfortunately, the prognosis for a dog already in liver failure when they get to us isn’t very good; however, those who do survive usually make a good recovery.

If you think your dog may have been exposed to Blue Green Algae - call us IMMEDIATELY!

If you see signs that you think might be of an Algal bloom, you should notify the Environment Agency so that they can test the water.