Ciguatera poisoning, or as we know it, fish poisoning, occurs all over the world in animals and people. We can’t cure it in animals, all we can do is make them comfortable, writes Dr Michael Baer, Te Are Manu Vet Clinic medical director.
The dog had wobbly
legs making lots of noise. He was excited but aware of what was happening and
trying to respond. But his head and limbs had more in common with one of those
inflatable advertising things that they put in front of car yards; you know the
ones, they flap everywhere. He was making little yip type noises constantly.
And his tongue was flapping around like a flag in a gale. We heard him coming in the drive, even over
the noise of the diesel motor. And we
were pretty sure we knew what was wrong with him.
Ciguatera
poisoning, or as we know it, fish poisoning, occurs all over the world. In
animals and people. In people the story goes back at least to European
explorers in the Caribbean, Indian and Pacific in the 1500s who provided the
earliest written records. It is fair to suspect there were cases before this
which were not written down. It is a bit later before reports in dogs and cats
appear on the scene. Aste cells, and muscle cells.
Fish poisoning is
a bit of a misnomer, the fish don’t make the poison. Rather it is made by
single celled alga, which in turn lives on dead and damaged coral. Herbivorous fish (like parrot) eat the algae,
then are eaten by carnivorous fish (like moray eels or trevally). The more
algae the fish eat, the more toxic they become. Because the toxic fish do not
taste any different, we eat them and feed them to our animals. And we and our
animals get poisoned.
Outbreaks happen
often, limited to certain areas or more widespread, where coral damage is
significant. Crown-of-thorns starfish, coral damage from waves and storms and
coral bleaching increase the food available to the algae, and so the amount of
toxin around. So we see more cases.
Why the wobbly
legs and all the noise? Why the floppy tongue? The poison affects nerves,
muscles and taste buds. People suffer diarrhoea and vomiting, followed by
tingling hands and feet, and numbness around their mouths. Some have
hallucinations or heart problems.
Dogs and cats have
a range of similar problems, but thing we see most are dogs that are very
wobbly or can’t move. With floppy tongues that won’t stay in their mouths. And
that make a lot of noise, yipping and groaning. Sometimes they have really
stiff front legs and really floppy back legs. They often crawl about, paddling
with funny movements of their legs, never quite managing to get their bodies
off the ground. Whether they hallucinate we don’t know.
We can’t cure it;
all we can do is make them comfortable. So, we stop the vomiting, the
diarrhoea. We treat them with painkillers if they are stiff and sore. We give them sedatives if they are anxious or
noisy. We explain to owners how to care for them, how to provide food and water
at room temperature and make sure they are on soft bedding.
And they get
better. Usually after about 10 days, but sometimes longer. People sometimes have
long lasting problems, similar to chronic fatigue syndrome. We don’t know about
dogs and cats.
So, please don’t
eat reef fish. Or feed it to your dogs and cats. And don’t let them eat
anything they find on the beach.