Ciguatera: the hidden toxin

Trout of this size are known Ciguatera carriers, especially when caught on the continental shelf area

By Nathan Billing

After recently becoming another unenviable statistic of someone who has contracted Ciguatera Poisoning, I thought I would do whatever is possible to make other people aware of this toxic poison and the risk that it poses in our area.

My Ciguatera poisoning symptoms showed after eating a 3kg blue spot coral trout from off Townsville. The trout I ate was by-catch from jigging for dog tooth tuna, and was 1 of 12 or so caught between 2 of us in the area between Faraday Shoals and Myrmidon Reefs one day in June, in water from between 60 and 90m deep. I now know of four mates (from separate fish and occasions), plus some of my family who have gotten Ciguatera from trout from this area. I will never eat a blue spot again, let alone from this area. Most of my mates now just chase red emperor/large mouth for the esky on the way out or way home, and all trout get released (in continental shelf waters at least). I know as you read this you’re thinking, stuff that, I’m not letting go a 65cm trout. I also had similar thoughts when a mate got Ciguatera off a trout from that area last year. Consider yourself warned… I had eaten a few trout with no issues, so thought he was unlucky and continued to eat them. I have changed my tune now. Never again!

We had a BBQ with family and friends on a Friday night and there were all sorts of meat, so a few of them ate a bit of trout, but it wasn’t much due to all the other meat available. As I found out later, the next day my brother and his wife had dull aching muscles and were itchy, but seeing as they were cutting down a tree in the back yard, thought nothing of it. Keep in mind here, my sister in law is from WA and had never eaten much fish until the last two or so years, and even so, she doesn’t eat that much. The leftover trout was put in the fridge that night, and come Sunday morning, yours truly is rummaging for some breakfast and spots a bowl full of coral trout. I asked around to see if anyone else wanted any and got told to heat it all up, and then, miraculously, no one wanted any. In the end, my father ate a little bit (maybe 300g) and I ate the remainder (maybe 800g) with some delicious lemon pepper sauce.

What is Ciguatera?
Ciguatera is a toxin that comes from Dinoflagellates, which are an organism that lives on algae and coral in some tropical waters. The toxin bio-accumulates in the food chain as small herbivorous fish inadvertently eat the Dinoflagellates while eating coral and algae. The bigger fish eat small fish, and the more small fish that have been eaten by the fish you eat, the higher the chance you have of consuming the ciguatera toxin. Saltwater fish were thought to not be affected by Ciguatera (as in made sick), however, recent research is indicating that it may kill off some fish that accumulate too much, and that different species have adapted to have higher tolerance than others. It is also interesting to note Ciguatera is lethal to freshwater fish. Common species that can be affected are sharks, barracuda, chinaman fish, cobia, coral cod, coral trout, flowery cod, groper, paddle tail, queenfish, red bass, red emperor, Spanish mackerel, spotted mackerel, sweetlip, trevally, triggerfish and up to 400 other species. Moray eels apparently have the highest concentrations, although I’m doubtful too many North Queenslanders are going to sit down for a feed of moray! According to the latest statistics from Queensland Health, 11 of 12 people who have reported getting Ciguatera poisoning in 2014 got it off Spanish mackerel, and 1 (myself) with coral trout. I am certain there are more but people don’t know to report it.

The Symptoms
Come midday Sunday, I had a pain in the stomach. I had to leave Townsville to drive back to Moranbah for work Monday morning, so thought I’d better get on the road at about 1pm. Before I left, I had a bout of diarrhoea and didn’t feel too well at all, but work is work and I had to be there, so I proceeded to drive. By the time I got to Alligator Creek I was busting for a toilet again like never before. I rolled into the car park, put the hand brake on and almost ran into the toilet. I did the rest of the six hour drive to Moranbah in a similar fashion, and the closer to Moranbah I got, the worse I felt (yes, lots of people who work there can probably relate, but I mean felt sick, not sick of work). During the drive my state had steadily worsened in my head as well. I was having major headaches (it’s a unique headache which seems to be at the base of your skull at the top of your spinal column and feels like someone is lifting your skull off), intermittent dizzy spells, blurry vision, pins and needles and a shocking metallic taste in my mouth. I let my dogs off the ute and put them in the back yard, locked my ute with the weekend’s fishing gear and clothes still in it, fell into bed and semi woke to my alarm Monday morning and texted my boss to say I wasn’t working. I slept the remainder of the day apart from trips to the toilet and the occasional work phone call which I couldn’t remember by the next day (only realised by customer complaints later!). By Monday night, I was starting to itch. No, I mean ITCH. I guarantee you have never ever itched like it. I was writhing in bed, bleeding from scratching my legs, arms, hands and feet. It felt like ants running around under my skin from the tips of my toes, up my legs, in my butt, up my back, under my scalp and every other possible place on my body. I can tell you, I’m not the small metro model of homo sapiens, but I cried from itching and these phantom ants. I’m pretty sure I had turned off my work phone at some point, and I slept from Monday night until Wednesday morning. I rung the doctors Wednesday and booked a midday appointment and on the way there discovered a few more symptoms. My eyes didn’t focus. Normally, as you walk, your eyes adjust for the horizon, but when you have Ciguatera, they no longer do that, so you get a feeling that you’re in zero gravity doing a moon walk. Also, I walked into walls, walked with a list to starboard, and at one point in the drive, went to put my foot on the brake and my foot didn’t move. Scary (yes, for the other driver too, I could see the whites of her eyes!). Also, my eyes were pumping tears flat out and I was developing blisters in my eyelids; my eyes felt like they were burning, and I swear I could see every blood vessel at three times its usual size. Over the next few days, I found I had also developed allergies to a lot of my normal foods. I discovered since while researching the topic that this is common and usually includes nuts, alcohol, seafood and eggs, but I also found out coffee, oats, bacon and lentils. Hot feels cold and cold feels hot and there are more muted symptoms you can’t comprehend until you’ve had it. I was off work for three weeks, almost bedridden, sleeping 24/7 for 2 of those. Despite all this, I was fortunate compared to some people. There is still a 1% fatality rate with Ciguatera and no known cure. Some people in Townsville spent weeks in ICU after eating contaminated Spanish mackerel from a fish shop a few years back. I tried a few things to try to fix it, both pharmacy medicine and charcoal, but didn’t notice an improvement with anything. On one occasion after shark was eaten by villagers in Madagascar 500 people contracted ciguatera, and 100 died.

How to prevent it!
Firstly, there is no reliable test kit. There are some kits that can test it available in the United States, but the concentration of Ciguatera has to be high and it will be hard to ever test with certainty due to the way that it can build up in your body and then just a small amount all of a sudden makes you sick.

The first real step is knowing your species. In week three of my torment, I was on Facebook a bit, and someone was asking “what fish is this?” with a pic of an Indonesian snapper (a lutjanid species) with its throat cut, on a popular buy/sell/swap page. I said on there, and I say again here, if you do not know what the fish is, do not keep it. Greed can get you and your family sick. We live in an area with Ciguatera poisoning being a distinct possibility, and lots of species look similar if you’re not living and breathing fishing. Ciguatera can be fatal, if you go home and feed a red bass to your kids or elderly parents thinking it’s a reef jack, you could kill them (unlikely, though possible). If not, you can make them feel miserable for a month. I don’t know how many times I’ve seen people incorrectly identify species, particularly on Facebook, and yes, some species are very similar, but I urge people to be 100% before they feed fish to their family.

Another point to note is incidences of Ciguatera are more common from fish caught on exposed sides of islands and reefs, probably the reason why we have seen this many trout causing Ciguatera from this area. I would also steer clear of any trout taken from the Flinders reef/coral sea areas if you have a boat that will get there. I now tell friends to avoid trout from the shelf area as a general rule. I personally think the pelagics would move around too much for location to be an accurate guide. I believe the best eating Spanish are school sized between legal and a metre anyway. By all means, have fun on the big ones, but let them go.

Prevention is better than cure. I was crook enough that I vow I will never eat another trout even after my 12 months of no seafood is up. From now on I will eat barra, threadies, creek jacks and maybe inshore fingermark and tusk fish. A simple rule is – if in doubt, throw it out.
People experiencing or having experienced what they believe to be Ciguatera fish poisoning should contact Queensland Health. This data is captured and is utilized when making future legislation e.g., determining no take species.

More information;

A red bass. Another innocent looking fish that could land you in a world of hurt, physically and financially.

 billing red bass 2 web