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Chinain M, Gatti Howell C, Roué M, Ung A, Henry K, Revel T, Cruchet P, Viallon J, Darius HT. Ciguatera poisoning in French Polynesia: A review of the distribution and toxicity of Gambierdiscus spp., and related impacts on food web components and human health. HARMFUL ALGAE 2023; 129:102525. [PMID: 37951623 DOI: 10.1016/j.hal.2023.102525] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 09/26/2023] [Accepted: 10/07/2023] [Indexed: 11/14/2023]
Abstract
Ciguatera Poisoning (CP) is a seafood poisoning highly prevalent in French Polynesia. This illness results from the consumption of seafood contaminated with ciguatoxins (CTXs) produced by Gambierdiscus, a benthic dinoflagellate. Ciguatera significantly degrades the health and economic well-being of local communities largely dependent on reef fisheries for their subsistence. French Polynesia has been the site of rich and active CP research since the 1960's. The environmental, toxicological, and epidemiological data obtained in the frame of large-scale field surveys and a country-wide CP case reporting program conducted over the past three decades in the five island groups of French Polynesia are reviewed. Results show toxin production in Gambierdiscus in the natural environment may vary considerably at a temporal and spatial scale, and that several locales clearly represent Gambierdiscus spp. "biodiversity hotspots". Current data also suggest the "hot" species G. polynesiensis could be the primary source of CTXs in local ciguateric biotopes, pending formal confirmation. The prevalence of ciguatoxic fish and the CTX levels observed in several locales were remarkably high, with herbivores and omnivores often as toxic as carnivores. Results also confirm the strong local influence of Gambierdiscus spp. on the CTX toxin profiles characterized across multiple food web components including in CP-prone marine invertebrates. The statistics, obtained in the frame of a long-term epidemiological surveillance program established in 2007, point towards an apparent decline in the number of CP cases in French Polynesia as a whole; however, incidence rates remain dangerously high in some islands. Several of the challenges and opportunities, most notably those linked to the strong cultural ramifications of CP among local communities, that need to be considered to define effective risk management strategies are addressed.
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Affiliation(s)
- M Chinain
- Institut Louis Malardé (ILM), Laboratory of Marine Biotoxins, UMR 241-EIO (IFREMER, ILM, IRD, UPF), P.O. Box 30, Papeete, Tahiti 98713, French Polynesia.
| | - C Gatti Howell
- Institut Louis Malardé (ILM), Laboratory of Marine Biotoxins, UMR 241-EIO (IFREMER, ILM, IRD, UPF), P.O. Box 30, Papeete, Tahiti 98713, French Polynesia
| | - M Roué
- Institut de Recherche pour le Développement (IRD), UMR 241-EIO (IFREMER, ILM, IRD, UPF), P.O. Box 6570, Faa'a, Tahiti 98702, French Polynesia
| | - A Ung
- Institut Louis Malardé (ILM), Laboratory of Marine Biotoxins, UMR 241-EIO (IFREMER, ILM, IRD, UPF), P.O. Box 30, Papeete, Tahiti 98713, French Polynesia
| | - K Henry
- Institut Louis Malardé (ILM), Laboratory of Marine Biotoxins, UMR 241-EIO (IFREMER, ILM, IRD, UPF), P.O. Box 30, Papeete, Tahiti 98713, French Polynesia
| | - T Revel
- Institut Louis Malardé (ILM), Laboratory of Marine Biotoxins, UMR 241-EIO (IFREMER, ILM, IRD, UPF), P.O. Box 30, Papeete, Tahiti 98713, French Polynesia
| | - P Cruchet
- Institut Louis Malardé (ILM), Laboratory of Marine Biotoxins, UMR 241-EIO (IFREMER, ILM, IRD, UPF), P.O. Box 30, Papeete, Tahiti 98713, French Polynesia
| | - J Viallon
- Institut Louis Malardé (ILM), Laboratory of Marine Biotoxins, UMR 241-EIO (IFREMER, ILM, IRD, UPF), P.O. Box 30, Papeete, Tahiti 98713, French Polynesia
| | - H T Darius
- Institut Louis Malardé (ILM), Laboratory of Marine Biotoxins, UMR 241-EIO (IFREMER, ILM, IRD, UPF), P.O. Box 30, Papeete, Tahiti 98713, French Polynesia
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2
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Johnson-Arbor KK. Chronic Ciguatera Poisoning: A Case Report. Wilderness Environ Med 2023; 34:222-224. [PMID: 36870862 DOI: 10.1016/j.wem.2023.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 12/12/2022] [Accepted: 01/05/2023] [Indexed: 03/05/2023]
Abstract
Ciguatera is a common marine, toxin-borne illness caused by the consumption of fish that contain toxins that activate voltage-sensitive sodium channels. The clinical manifestations of ciguatera are typically self-limited, but chronic symptoms may occur in a minority of patients. This report describes a case of ciguatera poisoning with chronic symptoms, including pruritus and paresthesias. A 40-y-old man was diagnosed with ciguatera poisoning after consuming amberjack while vacationing in the US Virgin Islands. His initial symptoms, including diarrhea, cold allodynia, and extremity paresthesias, evolved into chronic, fluctuating paresthesias and pruritus that became worse after the consumption of alcohol, fish, nuts, and chocolate. After a comprehensive neurologic evaluation failed to reveal another cause for his symptoms, he was diagnosed with chronic ciguatera poisoning. His neuropathic symptoms were treated with duloxetine and pregabalin, and he was counseled to avoid foods that triggered his symptoms. Chronic ciguatera is a clinical diagnosis. Signs and symptoms of chronic ciguatera can include fatigue, myalgias, headache, and pruritus. The pathophysiology of chronic ciguatera is incompletely understood but may involve genetic factors or immune dysregulation. Treatment involves supportive care and avoidance of foods and environmental conditions that may exacerbate symptoms.
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Affiliation(s)
- Kelly K Johnson-Arbor
- MedStar Georgetown University Hospital, Washington, DC; National Capital Poison Center, Washington, DC.
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3
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do Prado Leite I, Menegotto A, da Cunha Lana P, Júnior LLM. A new look at the potential role of marine plastic debris as a global vector of toxic benthic algae. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:156262. [PMID: 35643140 DOI: 10.1016/j.scitotenv.2022.156262] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 05/09/2022] [Accepted: 05/23/2022] [Indexed: 06/15/2023]
Abstract
Marine plastic debris provides a significant surface area for potential colonization by planktonic and benthic harmful microalgae and for the adsorption of their toxins. Furthermore, floating plastics may substantially expand the substrate area available for benthic algae in the ocean, intensifying the transfer of potent toxins through pelagic food webs. In this study, we quantify the available surface area of micro- and macroplastics in different oceanic regions and assess the potential role of floating plastics as vectors for the transfer of toxins from three widespread benthic dinoflagellates, Gambierdiscus spp., Ostreopsis cf. ovata and Prorocentrum lima. To avoid bias associated to the occurrence of benthic algae in deep waters, we selected only records from 0 to 100 m depths. We estimate that 26.8 × 1010 cm2 of plastic surface area is potentially available in surface waters of the global ocean, mostly in the size range of large microplastics (1.01-4.75 mm). Based on the distribution of floating plastics and the habitat suitability of the selected microalgal species, the plastic relative colonization risks will be greater in the Mediterranean Sea and in the subtropical and temperate western margins of the oceans, such as the North American and Asian eastern coasts and, to a lesser extent, southern Brazil and Australia. In places where the colonization of O. cf. ovata cells on floating plastic debris has been properly quantified, such as the Mediterranean and southern Brazil, we estimate a colonization potential of up to 2 × 106 cells km-2 of ocean surface during the regular occurrence period and up to 1.7 × 108 cells km-2 during massive blooms of this species. As plastic pollution and harmful benthic algal blooms have both increased substantially over the past decades, we suggest that their interactive effects can become a major and novel threat to marine ecosystems and human health.
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Affiliation(s)
- Isabel do Prado Leite
- Center for Marine Studies, Federal University of Paraná, Av. Beira-mar, s/n, 61, Pontal do Paraná, PR 83255-976, Brazil.
| | - André Menegotto
- Department of Ecology, Federal University of Goiás, Av. Esperança, s/n, Campus Samambaia, Goiânia, GO 74690-900, Brazil
| | - Paulo da Cunha Lana
- Center for Marine Studies, Federal University of Paraná, Av. Beira-mar, s/n, 61, Pontal do Paraná, PR 83255-976, Brazil
| | - Luiz Laureno Mafra Júnior
- Center for Marine Studies, Federal University of Paraná, Av. Beira-mar, s/n, 61, Pontal do Paraná, PR 83255-976, Brazil
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Concentrations of Tetrodotoxin (TTX) and Its Analogue 4,9-Anhydro TTX in Different Tissues of the Silver-Cheeked Pufferfish (Lagocephalus sceleratus, Gmelin, 1789) Caught in the South-Eastern Mediterranean Sea, Lebanon. Toxins (Basel) 2022; 14:toxins14020123. [PMID: 35202150 PMCID: PMC8877804 DOI: 10.3390/toxins14020123] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/20/2021] [Accepted: 12/20/2021] [Indexed: 11/28/2022] Open
Abstract
Pufferfishes are among the best-known marine organisms that accumulate marine biotoxins such as Tetrodotoxin (TTX). In the Mediterranean Sea, the silver-cheeked toadfish Lagocephalus sceleratus is the most reported TTX-bearer, causing many fatal and non-fatal cases. In Lebanon, no previous studies have measured TTX levels although the possibility of TTX-poisoning is high since L. sceleratus is caught in different sizes and can be mistaken with other small fishes. Hence, this study reports TTX and its analogue 4,9-anhydro TTX in L. sceleratus collected from Lebanese waters in the Eastern Mediterranean Sea. The results show that TTX concentrations in fish tissues varied between 0.10 and 252.97 µg/g, while those of 4,9-anhydro TTX oscillated between 0.01 and 43.01 µg/g. Internal organs of L. sceleratus were the most toxic parts of its body, with the highest TTX levels found in gonads (mainly ovaries) and liver, followed by the muscles and skin with concentrations always exceeding the safety level. Toxicity fluctuations of L. sceleratus, its expansion, ecological and economic effects were also elucidated. Based on the present findings, it has been confirmed that L. sceleratus constitutes a health, ecological and economic risks, and therefore its trade in seafood markets should be banned to avoid any potential intoxication.
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Chinain M, Gatti CMI, Darius HT, Quod JP, Tester PA. Ciguatera poisonings: A global review of occurrences and trends. HARMFUL ALGAE 2021; 102:101873. [PMID: 33875186 DOI: 10.1016/j.hal.2020.101873] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 07/17/2020] [Accepted: 07/22/2020] [Indexed: 06/12/2023]
Abstract
Ciguatera Poisoning (CP) is the most prevalent, phycotoxin related seafood poisoning across the globe, affecting between 10,000 and 50,000 people annually. This illness results from the consumption of seafood contaminated with lipid soluble toxins known as ciguatoxins (CTXs) that are produced by benthic dinoflagellates in the genera Gambierdiscus and Fukuyoa. The present work reviews the global occurrence of CP events and outbreaks, based on both scientific and gray literature. Ciguatera prevalence is significantly underestimated due to a lack of recognition of ciguatera symptoms, limited collection of epidemiological data on a global level, and reticence to report ciguatera in CP-endemic regions. Analysis of the time-series data available for a limited number of countries indicates the highest incidence rates are consistently reported from two historical CP-endemic areas i.e., the Pacific and Caribbean regions, a situation due in part to the strong reliance of local communities on marine resources. Ciguatera-related fatalities are rare (<0.1% of reported cases). The vast majority of outbreaks involve carnivorous fish including snappers, groupers, wrasses, and barracudas. Since 2000, an expansion of the geographical range of CP has been observed in several areas like Macaronesia and east and southeast Asia. In some of these locales, random surveys confirmed the presence of CTXs in locally sourced fish, consistent with the concurrent report of novel CP incidents (e.g., Canary Islands, Madeira, Selvagens Islands, New South Wales). One characteristic of outbreaks occurring in Asia is that they often present as large disease clusters due to group consumption of a single contaminated fish. Similar observations are reported from the Indian Ocean in the form of shark poisoning outbreaks which often lead to singular types of CP characterized by a high fatality rate. Other atypical forms of CP linked to the consumption of marine invertebrates also have been documented recently. Owing to the significant health, socioeconomic and socio-cultural impacts of ciguatera, there is an urgent need for increased, standardized, coordinated efforts in ciguatera education, monitoring and research programs. Several regional and international initiatives have emerged recently, that may help improve patients' care, data collection at a global scale, and risk monitoring and management capabilities in countries most vulnerable to CP's toxic threat.
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Affiliation(s)
- M Chinain
- Laboratory of Marine Biotoxins, Institut Louis Malardé - UMR 241 EIO, BP 30, 98713 Papeete, Tahiti, French Polynesia.
| | - C M I Gatti
- Laboratory of Marine Biotoxins, Institut Louis Malardé - UMR 241 EIO, BP 30, 98713 Papeete, Tahiti, French Polynesia
| | - H T Darius
- Laboratory of Marine Biotoxins, Institut Louis Malardé - UMR 241 EIO, BP 30, 98713 Papeete, Tahiti, French Polynesia
| | - J-P Quod
- ARVAM-Pareto, Technopole de la Réunion, 14 rue Henri Cornu, 97490 Sainte-Clotilde, La Réunion, France
| | - P A Tester
- Ocean Tester, LLC, 295 Dills Point Road, Beaufort, NC 28516, USA
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Neves RAF, Pardal MA, Nascimento SM, Silva A, Oliveira PJ, Rodrigues ET. High sensitivity of rat cardiomyoblast H9c2(2-1) cells to Gambierdiscus toxic compounds. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2020; 223:105475. [PMID: 32325308 DOI: 10.1016/j.aquatox.2020.105475] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Revised: 03/18/2020] [Accepted: 03/18/2020] [Indexed: 06/11/2023]
Abstract
Ciguatera fish poisoning is a frequently reported non-bacterial food-borne illness related to the consumption of seafood contaminated with ciguatoxins, and possibly maitotoxins. These toxins are synthesized by marine dinoflagellate species of Gambierdiscus and Fukuyoa genera, and their abundance is a matter of great concern due to their adverse effects to aquatic life and human health. The present study aims to assess the sensitivity of rat cardiomyoblast H9c2(2-1) cells to Gambierdiscus toxic compounds using concentration- and time-dependent sulforhodamine B (SRB) colorimetric assays. Low concentrations of Gambierdiscus extracts (corresponding to 1.3-2.3 cells mL-1) induced a concentration-dependent response. Specificity in time-dependent response of H9c2(2-1) cells was demonstrated for G. excentricus after a 180 min exposure compared to both G. cf. belizeanus and G. silvae species, with EC50s obtained after 720 and 360 min, respectively. The sensitivity of H9c2(2-1) cells to dinoflagellate toxic compounds was also tested with other genera from benthic (Coolia malayensis, Ostreopsis cf. ovata, Prorocentrum hoffmannianum and P. lima) and planktonic (Amphidinium carterae and Lingulodinium polyedrum) habitats. Amphidinium, Coolia and Lingulodinium data did not present any concentration-response relationships, and EC50 values could only be obtained after 720 and 1440 min of exposure to both Prorocentrum species and O. cf. ovata, respectively. This study demonstrated that the H9c2(2-1) SRB assay represents a promising and sensitive tool for the detection of Gambierdiscus toxic compounds present in water samples, particularly of G. excentricus at very low cell abundances.
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Affiliation(s)
- Raquel A F Neves
- Department of Ecology and Marine Resources, Federal University of the State of Rio de Janeiro (UNIRIO), Av Pasteur 458-307, 22290-240, Rio de Janeiro, Brazil; CFE-Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal.
| | - Miguel A Pardal
- CFE-Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal.
| | - Silvia M Nascimento
- Department of Ecology and Marine Resources, Federal University of the State of Rio de Janeiro (UNIRIO), Av Pasteur 458-307, 22290-240, Rio de Janeiro, Brazil.
| | - Alexandra Silva
- Phytoplankton Laboratory, Division of Oceanography and Environment, Portuguese Institute for the Sea and Atmosphere (IPMA), Rua Alfredo Magalhães Ramalho 6, 1495-006, Lisboa, Portugal.
| | - Paulo J Oliveira
- CNC-Centre for Neuroscience and Cell Biology, University of Coimbra Biotech Building, Lot 8A, Biocant Park, 3060-197, Cantanhede, Portugal.
| | - Elsa T Rodrigues
- CFE-Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal.
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Raman R, Coppes S, Hellingman T, Laclé C. Junctional bradycardia caused by ciguatera intoxication. BMJ Case Rep 2019; 12:12/5/e229354. [PMID: 31151977 DOI: 10.1136/bcr-2019-229354] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Ciguatera is a common but underreported tropical disease caused by the consumption of coral reef fish contaminated by ciguatoxins. Gastrointestinal and neurological symptoms predominate, but may be accompanied by cardiovascular features such as hypotension and sinus bradycardia. Here, we report an unusual case of junctional bradycardia caused by ciguatera in the Caribbean; to our knowledge, the first such report from the region. An increase in global sea temperatures is predicted to lead to the spread of ciguatera beyond traditional endemic areas, and the globalisation of trade in coral reef fish has resulted in sporadic cases occurring in developed countries far away from endemic areas. This case serves as a reminder to consider environmental intoxications such as ciguatera within the differential diagnosis of bradycardias.
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Affiliation(s)
- Rajendra Raman
- Accident and Emergency, NHS Fife, Kirkcaldy, UK.,Emergency Department, Dr Horacio E Oduber Hospital, Oranjestad, Aruba
| | - Sarah Coppes
- Emergency Department, Dr Horacio E Oduber Hospital, Oranjestad, Aruba.,Emergency Department, Spaarne Gasthuis, Haarlem, The Netherlands
| | - Tessa Hellingman
- Emergency Department, Dr Horacio E Oduber Hospital, Oranjestad, Aruba.,VU medisch centrum School of Medical Sciences, Amsterdam, The Netherlands
| | - Casper Laclé
- Emergency Department, Dr Horacio E Oduber Hospital, Oranjestad, Aruba
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8
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Litaker RW, Holland WC, Hardison DR, Pisapia F, Hess P, Kibler SR, Tester PA. Ciguatoxicity of Gambierdiscus and Fukuyoa species from the Caribbean and Gulf of Mexico. PLoS One 2017; 12:e0185776. [PMID: 29045489 PMCID: PMC5646788 DOI: 10.1371/journal.pone.0185776] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2017] [Accepted: 09/19/2017] [Indexed: 11/22/2022] Open
Abstract
Dinoflagellate species belonging to the genera Gambierdiscus and Fukuyoa produce ciguatoxins (CTXs), potent neurotoxins that concentrate in fish causing ciguatera fish poisoning (CFP) in humans. While the structures and toxicities of ciguatoxins isolated from fish in the Pacific and Caribbean are known, there are few data on the variation in toxicity between and among species of Gambierdiscus and Fukuyoa. Quantifying the differences in species-specific toxicity is especially important to developing an effective cell-based risk assessment strategy for CFP. This study analyzed the ciguatoxicity of 33 strains representing seven Gambierdiscus and one Fukuyoa species using a cell based Neuro-2a cytotoxicity assay. All strains were isolated from either the Caribbean or Gulf of Mexico. The average toxicity of each species was inversely proportional to growth rate, suggesting an evolutionary trade-off between an investment in growth versus the production of defensive compounds. While there is 2- to 27-fold variation in toxicity within species, there was a 1740-fold difference between the least and most toxic species. Consequently, production of CTX or CTX-like compounds is more dependent on the species present than on the random occurrence of high or low toxicity strains. Seven of the eight species tested (G. belizeanus, G. caribaeus, G. carolinianus, G. carpenteri, Gambierdiscus ribotype 2, G. silvae and F. ruetzleri) exhibited low toxicities, ranging from 0 to 24.5 fg CTX3C equivalents cell-1, relative to G. excentricus, which had a toxicity of 469 fg CTX3C eq. cell-1. Isolates of G. excentricus from other regions have shown similarly high toxicities. If the hypothesis that G. excentricus is the primary source of ciguatoxins in the Atlantic is confirmed, it should be possible to identify areas where CFP risk is greatest by monitoring only G. excentricus abundance using species-specific molecular assays.
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Affiliation(s)
- R. Wayne Litaker
- National Ocean Service, National Centers for Coastal Ocean Science, Center for Coastal Fisheries and Habitat Research, Beaufort, North Carolina, United States of America
- * E-mail:
| | - William C. Holland
- National Ocean Service, National Centers for Coastal Ocean Science, Center for Coastal Fisheries and Habitat Research, Beaufort, North Carolina, United States of America
| | - D. Ransom Hardison
- National Ocean Service, National Centers for Coastal Ocean Science, Center for Coastal Fisheries and Habitat Research, Beaufort, North Carolina, United States of America
| | - Francesco Pisapia
- L'Institut Français de Recherche pour l'Exploitation de la Mer, Laboratoire Phycotoxines, Nantes, France
| | - Philipp Hess
- L'Institut Français de Recherche pour l'Exploitation de la Mer, Laboratoire Phycotoxines, Nantes, France
| | - Steven R. Kibler
- National Ocean Service, National Centers for Coastal Ocean Science, Center for Coastal Fisheries and Habitat Research, Beaufort, North Carolina, United States of America
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An Updated Review of Ciguatera Fish Poisoning: Clinical, Epidemiological, Environmental, and Public Health Management. Mar Drugs 2017; 15:md15030072. [PMID: 28335428 PMCID: PMC5367029 DOI: 10.3390/md15030072] [Citation(s) in RCA: 172] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/13/2017] [Accepted: 02/13/2017] [Indexed: 01/07/2023] Open
Abstract
Ciguatera Fish Poisoning (CFP) is the most frequently reported seafood-toxin illness in the world. It causes substantial human health, social, and economic impacts. The illness produces a complex array of gastrointestinal, neurological and neuropsychological, and cardiovascular symptoms, which may last days, weeks, or months. This paper is a general review of CFP including the human health effects of exposure to ciguatoxins (CTXs), diagnosis, human pathophysiology of CFP, treatment, detection of CTXs in fish, epidemiology of the illness, global dimensions, prevention, future directions, and recommendations for clinicians and patients. It updates and expands upon the previous review of CFP published by Friedman et al. (2008) and addresses new insights and relevant emerging global themes such as climate and environmental change, international market issues, and socioeconomic impacts of CFP. It also provides a proposed universal case definition for CFP designed to account for the variability in symptom presentation across different geographic regions. Information that is important but unchanged since the previous review has been reiterated. This article is intended for a broad audience, including resource and fishery managers, commercial and recreational fishers, public health officials, medical professionals, and other interested parties.
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10
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Inserra MC, Israel MR, Caldwell A, Castro J, Deuis JR, Harrington AM, Keramidas A, Garcia-Caraballo S, Maddern J, Erickson A, Grundy L, Rychkov GY, Zimmermann K, Lewis RJ, Brierley SM, Vetter I. Multiple sodium channel isoforms mediate the pathological effects of Pacific ciguatoxin-1. Sci Rep 2017; 7:42810. [PMID: 28225079 PMCID: PMC5320492 DOI: 10.1038/srep42810] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 01/13/2017] [Indexed: 01/04/2023] Open
Abstract
Human intoxication with the seafood poison ciguatoxin, a dinoflagellate polyether that activates voltage-gated sodium channels (NaV), causes ciguatera, a disease characterised by gastrointestinal and neurological disturbances. We assessed the activity of the most potent congener, Pacific ciguatoxin-1 (P-CTX-1), on NaV1.1–1.9 using imaging and electrophysiological approaches. Although P-CTX-1 is essentially a non-selective NaV toxin and shifted the voltage-dependence of activation to more hyperpolarising potentials at all NaV subtypes, an increase in the inactivation time constant was observed only at NaV1.8, while the slope factor of the conductance-voltage curves was significantly increased for NaV1.7 and peak current was significantly increased for NaV1.6. Accordingly, P-CTX-1-induced visceral and cutaneous pain behaviours were significantly decreased after pharmacological inhibition of NaV1.8 and the tetrodotoxin-sensitive isoforms NaV1.7 and NaV1.6, respectively. The contribution of these isoforms to excitability of peripheral C- and A-fibre sensory neurons, confirmed using murine skin and visceral single-fibre recordings, reflects the expression pattern of NaV isoforms in peripheral sensory neurons and their contribution to membrane depolarisation, action potential initiation and propagation.
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Affiliation(s)
- Marco C Inserra
- Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, 306 Carmody Rd, St Lucia, Queensland 4072, Australia
| | - Mathilde R Israel
- Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, 306 Carmody Rd, St Lucia, Queensland 4072, Australia
| | - Ashlee Caldwell
- Visceral Pain Group, South Australian Health and Medical Research Institute (SAHMRI), School of Medicine, Flinders University, Adelaide, South Australia 5000, Australia.,Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, South Australian Health and Medical Research Institute (SAHMRI), North Terrace, Adelaide, South Australia 5000, Australia
| | - Joel Castro
- Visceral Pain Group, South Australian Health and Medical Research Institute (SAHMRI), School of Medicine, Flinders University, Adelaide, South Australia 5000, Australia.,Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, South Australian Health and Medical Research Institute (SAHMRI), North Terrace, Adelaide, South Australia 5000, Australia
| | - Jennifer R Deuis
- Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, 306 Carmody Rd, St Lucia, Queensland 4072, Australia
| | - Andrea M Harrington
- Visceral Pain Group, South Australian Health and Medical Research Institute (SAHMRI), School of Medicine, Flinders University, Adelaide, South Australia 5000, Australia.,Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, South Australian Health and Medical Research Institute (SAHMRI), North Terrace, Adelaide, South Australia 5000, Australia
| | - Angelo Keramidas
- Queensland Brain Institute, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Sonia Garcia-Caraballo
- Visceral Pain Group, South Australian Health and Medical Research Institute (SAHMRI), School of Medicine, Flinders University, Adelaide, South Australia 5000, Australia.,Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, South Australian Health and Medical Research Institute (SAHMRI), North Terrace, Adelaide, South Australia 5000, Australia
| | - Jessica Maddern
- Visceral Pain Group, South Australian Health and Medical Research Institute (SAHMRI), School of Medicine, Flinders University, Adelaide, South Australia 5000, Australia.,Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, South Australian Health and Medical Research Institute (SAHMRI), North Terrace, Adelaide, South Australia 5000, Australia
| | - Andelain Erickson
- Visceral Pain Group, South Australian Health and Medical Research Institute (SAHMRI), School of Medicine, Flinders University, Adelaide, South Australia 5000, Australia.,Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, South Australian Health and Medical Research Institute (SAHMRI), North Terrace, Adelaide, South Australia 5000, Australia
| | - Luke Grundy
- Visceral Pain Group, South Australian Health and Medical Research Institute (SAHMRI), School of Medicine, Flinders University, Adelaide, South Australia 5000, Australia.,Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, South Australian Health and Medical Research Institute (SAHMRI), North Terrace, Adelaide, South Australia 5000, Australia
| | - Grigori Y Rychkov
- Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, South Australian Health and Medical Research Institute (SAHMRI), North Terrace, Adelaide, South Australia 5000, Australia
| | - Katharina Zimmermann
- Klinik für Anästhesiologie am Universitätsklinikum Erlangen, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Richard J Lewis
- Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, 306 Carmody Rd, St Lucia, Queensland 4072, Australia
| | - Stuart M Brierley
- Visceral Pain Group, South Australian Health and Medical Research Institute (SAHMRI), School of Medicine, Flinders University, Adelaide, South Australia 5000, Australia.,Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, South Australian Health and Medical Research Institute (SAHMRI), North Terrace, Adelaide, South Australia 5000, Australia
| | - Irina Vetter
- Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, 306 Carmody Rd, St Lucia, Queensland 4072, Australia.,School of Pharmacy, The University of Queensland, 20 Cornwall St, Woolloongabba, Queensland 4102, Australia
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11
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Bahna SL. Not every seafood "allergy" is allergy! Ann Allergy Asthma Immunol 2016; 117:458-461. [PMID: 27788870 DOI: 10.1016/j.anai.2016.04.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 04/15/2016] [Accepted: 04/18/2016] [Indexed: 01/27/2023]
Affiliation(s)
- Sami L Bahna
- Allergy & Immunology Section, Louisiana State University Health, Shreveport, Louisiana.
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12
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Acute Exposure to Pacific Ciguatoxin Reduces Electroencephalogram Activity and Disrupts Neurotransmitter Metabolic Pathways in Motor Cortex. Mol Neurobiol 2016; 54:5590-5603. [PMID: 27613284 DOI: 10.1007/s12035-016-0093-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 09/01/2016] [Indexed: 12/14/2022]
Abstract
Ciguatera fish poisoning (CFP) is a common human food poisoning caused by consumption of ciguatoxin (CTX)-contaminated fish affecting over 50,000 people worldwide each year. CTXs are classified depending on their origin from the Pacific (P-CTXs), Indian Ocean (I-CTXs), and Caribbean (C-CTXs). P-CTX-1 is the most toxic CTX known and the major source of CFP causing an array of neurological symptoms. Neurological symptoms in some CFP patients last for several months or years; however, the underlying electrophysiological properties of acute exposure to CTXs remain unknown. Here, we used CTX purified from ciguatera fish sourced in the Pacific Ocean (P-CTX-1). Delta and theta electroencephalography (EEG) activity was reduced remarkably in 2 h and returned to normal in 6 h after a single exposure. However, second exposure to P-CTX-1 induced not only a further reduction in EEG activities but also a 2-week delay in returning to baseline EEG values. Ciguatoxicity was detected in the brain hours after the first and second exposure by mouse neuroblastoma assay. The spontaneous firing rate of single motor cortex neuron was reduced significantly measured by single-unit recording with high spatial resolution. Expression profile study of neurotransmitters using targeted profiling approach based on liquid chromatography-tandem mass spectrometry revealed an imbalance between excitatory and inhibitory neurotransmitters in the motor cortex. Our study provides a possible link between the brain oscillations and neurotransmitter release after acute exposure to P-CTX-1. Identification of EEG signatures and major metabolic pathways affected by P-CTX-1 provides new insight into potential biomarker development and therapeutic interventions.
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13
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Au NPB, Kumar G, Asthana P, Tin C, Mak YL, Chan LL, Lam PKS, Ma CHE. Ciguatoxin reduces regenerative capacity of axotomized peripheral neurons and delays functional recovery in pre-exposed mice after peripheral nerve injury. Sci Rep 2016; 6:26809. [PMID: 27229176 PMCID: PMC4882531 DOI: 10.1038/srep26809] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 05/10/2016] [Indexed: 01/03/2023] Open
Abstract
Ciguatera fish poisoning (CFP) results from consumption of tropical reef fish containing ciguatoxins (CTXs). Pacific (P)-CTX-1 is among the most potent known CTXs and the predominant source of CFP in the endemic region responsible for the majority of neurological symptoms in patients. Chronic and persistent neurological symptoms occur in some CFP patients, which often result in incomplete functional recovery for years. However, the direct effects of exposure to CTXs remain largely unknown. In present study, we exposed mice to CTX purified from ciguatera fish sourced from the Pacific region. P-CTX-1 was detected in peripheral nerves within hours and persisted for two months after exposure. P-CTX-1 inhibited axonal regrowth from axotomized peripheral neurons in culture. P-CTX-1 exposure reduced motor function in mice within the first two weeks of exposure before returning to baseline levels. These pre-exposed animals exhibited delayed sensory and motor functional recovery, and irreversible motor deficits after peripheral nerve injury in which formation of functional synapses was impaired. These findings are consistent with reduced muscle function, as assessed by electromyography recordings. Our study provides strong evidence that the persistence of P-CTX-1 in peripheral nerves reduces the intrinsic growth capacity of peripheral neurons, resulting in delayed functional recovery after injury.
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Affiliation(s)
- Ngan Pan Bennett Au
- Department of Biomedical Sciences, City University of Hong Kong, Tat Chee Avenue, Hong Kong
| | - Gajendra Kumar
- Department of Biomedical Sciences, City University of Hong Kong, Tat Chee Avenue, Hong Kong
| | - Pallavi Asthana
- Department of Biomedical Sciences, City University of Hong Kong, Tat Chee Avenue, Hong Kong
| | - Chung Tin
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Hong Kong.,Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Tat Chee Avenue, Hong Kong
| | - Yim Ling Mak
- State Key Laboratory in Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Hong Kong.,Shenzhen Key Laboratory for the Sustainable Use of Marine Biodiversity, Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Leo Lai Chan
- Department of Biomedical Sciences, City University of Hong Kong, Tat Chee Avenue, Hong Kong.,State Key Laboratory in Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Hong Kong.,Shenzhen Key Laboratory for the Sustainable Use of Marine Biodiversity, Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Paul Kwan Sing Lam
- State Key Laboratory in Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Hong Kong.,Shenzhen Key Laboratory for the Sustainable Use of Marine Biodiversity, Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen, China.,Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong
| | - Chi Him Eddie Ma
- Department of Biomedical Sciences, City University of Hong Kong, Tat Chee Avenue, Hong Kong.,Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Tat Chee Avenue, Hong Kong.,State Key Laboratory in Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Hong Kong
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14
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Chan TYK. Characteristic Features and Contributory Factors in Fatal Ciguatera Fish Poisoning--Implications for Prevention and Public Education. Am J Trop Med Hyg 2016; 94:704-9. [PMID: 26787145 DOI: 10.4269/ajtmh.15-0686] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 12/08/2015] [Indexed: 11/07/2022] Open
Abstract
In this review, the main objective was to describe the characteristic features of fatal ciguatera fish poisoning and identify contributory factors, with a view to promote prevention and public education. Ciguatera-related deaths, although rare, have been reported from the Pacific, Caribbean, and Indian Ocean regions. The clinical features were generally dominated by convulsions and coma, with various focal neurological signs. Several contributory factors could be identified, including consumption of ciguatoxin (CTX)-rich fish parts (viscera and head) in larger amounts, the most ciguatoxic fish species (e.g.,Gymnothorax flavimarginatus) and reef fish collected after storms and individuals' susceptibility. Mass ciguatera fish poisoning with mortalities also occurred when G. flavimarginatus and other ciguatoxic fish species were shared in gatherings and parties. The characteristic features of fatal ciguatera fish poisoning must be recognized early. The public should be repeatedly reminded to avoid eating the most ciguatoxic fish species and the CTX-rich parts of reef fish. To prevent mass poisoning in gatherings and parties, the most ciguatoxic fish species and potentially toxic fish species must be avoided. Particularly after hits by disastrous storms, it is important to monitor the toxicity of reef fish and the incidence rates of ciguatera.
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Affiliation(s)
- Thomas Y K Chan
- Division of Clinical Pharmacology and Drug and Poisons Information Bureau, Department of Medicine and Therapeutics, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, China; Centre for Food and Drug Safety, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
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15
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Chan TYK. Ciguatoxic Potential of Brown-Marbled Grouper in Relation to Fish Size and Geographical Origin. Am J Trop Med Hyg 2015; 93:1117-21. [PMID: 26324735 DOI: 10.4269/ajtmh.15-0434] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 07/18/2015] [Indexed: 11/07/2022] Open
Abstract
To determine the ciguatoxic potential of brown-marbled grouper (Epinephelus fuscoguttatus) in relation to fish size and geographical origin, this review systematically analyzed: 1) reports of large ciguatera outbreaks and outbreaks with description of the fish size; 2) Pacific ciguatoxin (P-CTX) profiles and levels and mouse bioassay results in fish samples from ciguatera incidents; 3) P-CTX profiles and levels and risk of toxicity in relation to fish size and origin; 4) regulatory measures restricting fish trade and fish size preference of the consumers. P-CTX levels in flesh and size dependency of toxicity indicate that the risk of ciguatera after eating E. fuscoguttatus varies with its geographical origin. For a large-sized grouper, it is necessary to establish legal size limits and control measures to protect public health and prevent overfishing. More risk assessment studies are required for E. fuscoguttatus to determine the size threshold above which the risk of ciguatera significantly increases.
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Affiliation(s)
- Thomas Y K Chan
- Division of Clinical Pharmacology and Drug and Poisons Information Bureau, Department of Medicine and Therapeutics, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong, China; Centre for Food and Drug Safety, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
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16
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Zhang L, Lu L, Shu L, Chen J, Zou B, Zhou Q, Gu Y, Zhao J, Lin X. Association between the Hygiene Index Values of Live Fresh Aquatic Products and Food-Borne Diarrhea in the Population of the Ningbo Area in China. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2015; 12:9154-68. [PMID: 26258783 PMCID: PMC4555271 DOI: 10.3390/ijerph120809154] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Accepted: 07/29/2015] [Indexed: 12/03/2022]
Abstract
To investigate the association of the hygiene index values of live fresh aquatic products and food-borne diarrhea in the population of the Ningbo area in China. Volatile basic nitrogen (VBN), histamine (HIS), indole, tetrodotoxin (TTX), and paralytic, neurotoxic, amnesic and diarrhetic shellfish poisons (PSP, NSP, ASP, and DSP, respectively) in the samples of live fresh aquatic products and food-borne diarrhea cases in six studied districts were analyzed. Results indicate that the incidence rate of food-borne diarrhea is related to the hygiene index values. Aside from VBN, the main risk factors related to food-borne diarrhea in edible aquatic products include DSP (in marine fish, shrimp, and other shellfishes), NSP, and ASP (in marine shrimp and crab). Hygiene index values among different species were significantly different. No significant difference in the monitoring index values was found among the six different studied districts. The reported cases of food-borne diarrhea were positively associated with VBN and DSP in aquatic products in Haishu, Jiangbei, Zhenhai, and Beilun, as well as VBN and NSP in aquatic products in Jiangdong and Yinzhou. In conclusion, VBN, DSP, NSP, and ASP are important risk factors for the occurring of food-borne diarrhea in the population of the Ningbo area in China.
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Affiliation(s)
- Lijun Zhang
- Zhejiang Provincial Key Laboratory of Pathological and Physiological Technology, Medical School, Ningbo University, Ningbo 315211, China.
- Jiangdong Centers for Disease Control and Prevention, Ningbo 315040, China.
| | - Lu Lu
- Jiangdong Centers for Disease Control and Prevention, Ningbo 315040, China.
| | - Liye Shu
- Jiangdong Centers for Disease Control and Prevention, Ningbo 315040, China.
| | - Jianjun Chen
- Jiangdong Centers for Disease Control and Prevention, Ningbo 315040, China.
| | - Baobo Zou
- Zhejiang Provincial Key Laboratory of Pathological and Physiological Technology, Medical School, Ningbo University, Ningbo 315211, China.
| | - Qi Zhou
- Zhejiang Provincial Key Laboratory of Pathological and Physiological Technology, Medical School, Ningbo University, Ningbo 315211, China.
| | - Yuanliang Gu
- Zhejiang Provincial Key Laboratory of Pathological and Physiological Technology, Medical School, Ningbo University, Ningbo 315211, China.
| | - Jinshun Zhao
- Zhejiang Provincial Key Laboratory of Pathological and Physiological Technology, Medical School, Ningbo University, Ningbo 315211, China.
| | - Xialu Lin
- Zhejiang Provincial Key Laboratory of Pathological and Physiological Technology, Medical School, Ningbo University, Ningbo 315211, China.
- Key Laboratory of Trace Elements and Endemic Diseases of Ministry of Health, Health Science Center, School of Public Health, Xi'an Jiaotong University, Xi'an 710061, China.
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17
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Ciguatera fish poisoning in East Asia and southeast Asia. Mar Drugs 2015; 13:3466-78. [PMID: 26042615 PMCID: PMC4483640 DOI: 10.3390/md13063466] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 05/20/2015] [Accepted: 05/21/2015] [Indexed: 11/17/2022] Open
Abstract
In the coastal countries of East Asia and Southeast Asia, ciguatera should be common because of the extensive tropical and subtropical coral reefs along the coasts and in the neighboring seas with ciguatoxic fishes. An extensive search of journal databases, the Internet and the government websites was performed to identify all reports of ciguatera from the regions. Based on the official data and large published case series, the incidence of ciguatera was higher in the coastal cities (Hong Kong, Foshan, Zhongshan) of southern China than in Japan (Okinawa Prefecture). In Singapore, ciguatera appeared to be almost unknown. In other countries, only isolated cases or small case series were reported, but under-reporting was assumed to be common. Ciguatera may cause severe acute illness and prolonged neurological symptoms. Ciguatera represents an important public health issue for endemic regions, with significant socio-economic impact. Coordinated strategies to improve risk assessment, risk management and risk communication are required. The systematic collection of accurate data on the incidence and epidemiology of ciguatera should enable better assessment and management of its risk. Much more work needs to be done to define the size threshold for important coral reef fish species from different regions, above which the risk of ciguatera significantly increases.
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18
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Emergence and epidemiology of ciguatera in the coastal cities of southern China. Mar Drugs 2015; 13:1175-84. [PMID: 25738329 PMCID: PMC4377978 DOI: 10.3390/md13031175] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 01/22/2015] [Accepted: 02/11/2015] [Indexed: 11/20/2022] Open
Abstract
In the present review of 23 published case studies, the main objective is to report the emergence and epidemiology of ciguatera in the coastal cities of southern China. There was a sudden surge in ciguatera outbreaks in 2004. Ciguatera mostly occurred in the Guangdong Province. In Shenzhen, the incidence of ciguatera in 2004 was estimated to be over 7.5 per million people. In Foshan and Zhongshan, three large outbreaks each affecting over 100–200 subjects (caused by tiger grouper served at banquets) accounted for the much higher incidence of ciguatera in 2004 (>48.7 and >129.9 per million people). Humphead wrasse and areolated coral grouper were the other important ciguatoxic fish. In some subjects, risk factors for increased likelihood of (severe) ciguatera were present, namely concomitant alcohol consumption and ingestion of large reef fishes and CTX-rich fish parts. To prevent large outbreaks and severe illness, large apex predators from coral reefs should never be served at banquets and the public should realize the increased risk of severe symptoms due to ingestion of CTX-rich fish parts with alcohol. The systematic collection of accurate details, implementation of risk assessment process and continuing education for the public on prevention are of obvious importance.
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