Heavy poisoning by fish fillets

Poison alarm: Fish poisoning Ciguatera increasingly common in Europe

01/30/2015

The tropical fish poisoning Ciguatera occurs more and more in Europe. Most travelers are affected by the so-called endemic areas of the Pacific and the Caribbean. This particularly severe form of fish poisoning is triggered by ciguatoxins, toxic products of unicellular flagellates. In the human body, they can cause serious neurological problems, while not posing a risk to fish.

Heavy poisoning by ciguatoxins in tropical fish
The worldwide increase in cases of Ciguatera is attributed by experts to the ongoing destruction of the reefs and the rise in sea temperature. Because the disease-causing Ciguatoxine come from so-called dinoflagellates, which live in coral reefs on algae and seaweed. They serve the fish of the reef as food. Due to the slow but steady increase in sea temperature, the propagation of algae is promoted, informs the non-profit European Food Information Center EUFIC. As a result, more food is available. The poisonous ciguatoxins reach out within the food chain as follows: flagellates - algae - herbivore fish - predatory fish. The strongest hunters are affected, with barracuda, mackerel, snapper and grouper having the highest concentrations of toxins.

While the ciguatoxins are safe for the fish, they can cause serious poisoning in humans. „They already cause doses of 0.1 micrograms per kilogram of disease and often serious neurological problems. The contaminated fish are not recognizable by taste, texture or smell. In addition, ciguatoxins can not be inactivated - either by heating or freezing or by stomach acid. In frozen fish, they are virtually unlimited shelf life, "quotes the online edition of „The world“ Prof. Dr. Katharina Zimmermann from the University Hospital Erlangen. The anesthesiologist investigates the mechanism of hypersensitivity to ciguatoxin intoxication.

While Ciguatera used to only be in the tropics, experts now talk about a global threat. At least ten Ciguatera epidemics have been registered in the Canary Islands since 2008. The yellow tail mackerel (Yellowtail amberjack) was the most affected. In 2013, at least ten people fell ill with the dangerous fish poisoning. Since contaminated fish do not differ externally from other fish, it is very difficult to sort out affected fish. As a result, fish, some of which are even very heavily contaminated with toxins, are being marketed time and time again.

Dangerous fish poisoning can be associated with severe neurological problems
As part of her research, Zimmermann interviewed eleven affected persons about the severity and frequency of their symptoms of intoxication. „The initial symptoms were similar to those affected, "says the scientist. „About 45 minutes after fish consumption, the majority developed a burning sensation in the oral mucosa. After four to twelve hours diarrhea, nausea and vomiting followed. Characteristic is a drop in body temperature, which manifests itself as a general feeling of cold and was detected by all patients. This is often paired with freezing, which survives the acute intoxication phase. "

In addition, there is a strong itching, which made itself felt in almost all those affected and six to eight weeks after the fish consumption was still present. In individual cases, he even appeared after a year in the form of seizures. „Many of the patients complained of a long-term general feeling of weakness, accompanied by low resilience and easy fatigue, "reports Zimmermann. „This feeling of weakness persisted in isolated cases even over several months. Almost all those affected stated that they were freezing over at least one, on average over 3.5 weeks, ".

Other symptoms that can also occur over a long period of time include shaking, sweating, pain and a strong urge to urinate. Especially noticeable in Ciguatera is "the changed feeling of cold and warmth". Patients feel "cold water or cold air as hot".

Therapy of Ciguatera can only alleviate symptoms
Ciguatera is one of the diseases for which there is no causal therapy. Doctors can only alleviate the symptoms. In addition, infusions with the sugar alcohol mannitol may promote the excretion of the poison, provided that the treatment is given no later than two to three days after the consumption of the fish. Since the contaminated fish are externally indistinguishable from unencumbered, the Federal Institute for Risk Assessment (BfR) advises travelers in the affected regions to abandon the consumption of tropical fish.

In Germany, between 2000 and 2013, a total of 61 cases of ciguatera were registered at the poison information centers. Most tourists were affected who had eaten the contaminated fish during their trip. In this country, a major epidemic first occurred in November 2012. At that time, 20 people, mostly from northern Germany, suffered from the typical symptoms of fish poisoning. They had consumed imported fish fillets.

Warning of contaminated fish
The Federal Office of Consumer Protection and Food Safety is currently warning on its Internet portal „ www.lebensmittelwarnung.de“ before eating fish fillets of the brand PTC Snapper. The affected products were on sale in early December 2014 and have a sell-by date of 11.10. 2015 (Lot No. PTKVAC1301). The Indonesian fish may contain algae toxins that cause ciguatera. (Ag)

Picture: w.r.wagner