Ciguatera fish poisoning: A first epidemic in Germany highlights an increasing risk for European countries

Abstract

a b s t r a c tToxin-producing microalgae are thriving worldwide due to coral reef destruction and global warming with major consequences on ecosystems, international trade and human health. Microalgae belonging to the family of flagellate protists, in particular dinoflagellates, secrete a variety of high-molecular-weight polyether toxins that accumulate through the marine food chain to cause disease in humans by acting as sodium channel activator toxins; ciguatera is the most frequent seafood-borne illness worldwide with 50,000 to 500,000 global incidences per annum and is usually limited to endemic areas located between 35 northern and 35 southern latitude. The rising global incidence frequency renders it a major human health problem, because no curative treatment is available yet and reliable detection assays are lacking. During the last decade ciguatera has increasingly become endemic in previously unaffected areas for two reasons: first global warming has contributed to the emergence of dinoflagellate species in subtropical and even temperate regions that previously had been constrained to tropical areas and second: in Europe globalization of fishing industry and tourism has led to a progressive increase in the number of ciguatera cases and a lack of awareness among medical personnel contributes to under-reporting. We review, through a recent ciguatera outbreak in Germany, the risk for ciguatera poisoning in Europe and highlight characteristic symptoms, current knowledge about disease pathomechanisms and treatment options.

Ciguatera, an Emerging Human Poisoning in Europe

“…These poisoning outbreaks described reinforce the idea of the geographical spread of ciguatera endemic areas worldwide [17]. CFP outbreaks that occurs outside of endemic areasare often linked to consumption of imported toxic fish or in travelers returning from endemic CFP areas [6,17] as recently there have been reports of ciguatera poisoning in New York, Germany [11] and France [19].…”

“…CTXs inhibit Na + channel inactivation and shift their voltage dependence towards more negative potentials. Additionally they act as voltage-gated K + channel inhibitors [11]. This slows down re-polarization and keeps channels in an open, depolarized state that can ultimately lead to cell death.…”

Harmful Algal Blooms in Benthic Systems: Recent Progress and Future Research

“…Although CFP is endemic to tropical and subtropical areas, increased fish trade and tourism has resulted in "imported" cases of CFP in Europe, Canada, and the United States (e.g., Centers for Disease Control and Prevention, 2013;Mattei et al, 2014). Furthermore, CFP has also been reported in previously unaffected areas such as the coast of West Africa, Madeira, and the Canary Islands (Bienfang et al, 2008;Boada et al, 2010).…”

Ciguatoxin and Ciguatera

“…Interestingly, ciguatoxin does not elicit histamine release in skin and in humans; itch was described as a symptom preceding pain at very low concentrations, suggesting that ciguatoxin-induced pruritus is of neurogenic origin (Vetter et al 2012). Accordingly, the distribution of pruritus often occurs in a stockingglove pattern affecting predominantly the hands and feet (Mattei et al 2014b;Zimmermann et al 2015). Neuronal symptoms of central origin, including cerebellar dysfunction, as well as general weakness or fatigue also occur.…”

“…Neuronal symptoms of central origin, including cerebellar dysfunction, as well as general weakness or fatigue also occur. Notably, a drop in body temperature, accompanied by chills or sweating, is commonly observed in ciguatera patients (Mattei et al 2014b) and has been experimentally reproduced in rodents Morey et al 2008;Peng et al 1995). Peripheral neurological symptoms typically develop over several days and can persist for weeks and often months and occasionally for years.…”