Anisakis Simplex Larvae Research Articles

Anisakiasis outbreak by Anisakis simplex larvae associated to Peruvian food in Spain

Anisakiasis outbreak by Anisakis simplex larvae associated to Peruvian food in Spain

Infection and physico-chemical characteristics of Anisakis among marine fish caught in Zhoushan Fishery

To study the rates of infection and physicochemical characteristics of the third stage Anisakis simplex larvae among marine fish caught in Zhoushan Fishery. Fish were dissected to detect Anisakis larvae and identified morphologically. The survival tolerance of the third stage Anisakis simplex larvae in various medium, anthelmintic drug, temperature were studied in laboratory. The total infection rate of Anisakis simplex larvae in fish was 49.10%. High rates of Anisakis infection were observed in hairtails, Pneumatophorus japonicus, Miichthys milky, Argyrosomus argentatus and Muraenesox cinereus (infection rates > 90 percent). The infection intensity of Anisakis per fish varied from 1 to 114. The mean intensity of Anisakis larvae was 15.20 per fish. 3314 Anisakis were detected in 218 marine fish. The survival tolerance of the third stage Anisakis simplex larvae in various Medium, anthelmintic drug, temperature were observed in laboratory condition. The third stage Anisakis simplex larvae showed a strong endurance to stock condiment. The anisakicidal effects of the high purity wine were more effective than that of the low purity wine. The anisakicidal effects of 6.25 g/L mebendazole composite were more effective than that of 18.75 g/L and also more effective than those of other drugs. The third stage Anisakis simplex larvae could survive with length up to 9 h and 12 h in condition of -20°C, -10°C and very sensitive to high temperature treatment. However, they could barely survive in more than 11 s and 1 s under the temperature of 50°C and 60°C. The percentage of infection was fairly high for Anisakis larvae of marine fish caught in Zhoushan Fishery. The third stage Anisakis simplex larvae was shown to have a fairly good tolerance to the external environments. The marine fish were frozen under -20°C beyond 24 h before they were sold on market and cooked with high temperature seemed to be helpful for preventing and controlling effectively the infection of Anisakis.

Anisakis simplex third stage larvae in Norwegian spring spawning herring (Clupea harengus L.), with emphasis on larval distribution in the flesh

The third stage larvae of the parasitic nematode Anisakis simplex commonly occur in most commercially important fish species of the North Atlantic, including Norwegian spring spawning herring (Clupea harengus L.). The presence of nematode larvae in the flesh of fish may significantly lower the aesthetical quality of the product, or even pose a consumer health risk, especially with regard to the possible allergenic nature of the larvae or molecular traces thereof. In this study, the occurrence and spatial distribution of A. simplex larvae in comparable size groups of Norwegian spring spawning herring caught in the north-eastern Norwegian Sea in October 2004 and in the outer basin of Vestfjorden, northern Norway, in November 2007, was investigated. Emphasis was put on manually- and industrially produced, i.e. automatically trimmed and skinned fillets of herring. The overall larval prevalence was 98-100% in the herring of all size groups and the abundance increased with increasing body weight in both sampling years. On an average 3.5% of the larvae were found in the belly flaps, i.e. the ventral portion of the body musculature covering the visceral cavity on both sides, while 0.5% occurred in the dorsal part of the fillets. The larval prevalence varied from 42 to 70% and 8 to 10% in the manually- and industrially produced fillets, respectively. Thus, any product that is based on industrially produced fillets of Norwegian spring spawning herring may still carry nematode larvae when put on the market. However, compared to the manually produced ones, especially those untrimmed, the probability of A. simplex larvae to be present in industrially produced fillets appears to be approximately 5-8 times lower.

Narrow band imaging enhancement could improve gastric anisakis detection

Gastrointestinal anisakiasis is a parasitic disease acquired by humans after ingestion of raw fish infected with third stage larvae of the nematode Anisakis simplex. Even if considered a rare disease in Western countries, it is underestimated in many Italian regions with large fishing-based activities and widespread consumption of raw sea food.

Anisakis survival in refrigerated fish products under CO 2 modified-atmosphere

With the aim to assess the survival of Anisakis infection in fish stored under CO 2 modified-atmosphere, third-stage larvae (L3) of Anisakis simplex were inoculated in samples of skinless fish musculature and then packaged in three different CO 2 modified-atmospheres commonly used to preserved fresh fish products. The microenvironment provided by CO 2 modified-atmosphere packaging (MAP) does not impair the well-being and somatic antigenic properties of Anisakis larvae in infected fresh fish. This result indicates that MAP does not protect against anisakiasis risk. Therefore proactive regular inspections in commercial fresh fish should be done by MAP operators in fishery industries to ensure that healthy products (i.e., parasite-free fish products) reach the consumer, thus accomplishing with the co-responsibility criterion established in the EU food hygiene legislation.

Third-Stage Larvae of Anisakis simplex (Rudolphi, 1809) in the Red Sea Fishes, Yemen Coast

There is much less information on the occurrence of parasitic nematodes in the Red Sea fish, Yemeni Coast, therefore, the aim of this study was to assess the anisakid nematode distribution pattern in the fish collected from fish market (Al-Mehwat) in the Hodeidah City, during the period between January 2006 - March 2007.

Effect of crude extract of anisakis simplex larvae on activation of human eosinophils

Effect of crude extract of anisakis simplex larvae on activation of human eosinophils

Inactivation of Anisakis simplex larvae in raw fish using high hydrostatic pressure treatments

The nematode larvae of the Anisakis genus are one of the main health hazards for consumers of raw fish or similar, such as “carpaccio”, and cold smoked or marinated products. This study evaluated the efficacy of high hydrostatic pressure treatments on Anisakis larvae in mackerel ( Scomber scombrus) from the North Sea. From the treatment parameters studied, a combination of 300 MPa for 5 min resulted as being capable of inactivating 100% of the larvae present in the tissues of the fish treated. Biomolecular examination confirmed their main belonging to the species Anisakis simplex sensu stricto. The use of this technology is for the treatment of other fatty fish such as sardines and anchovies prior to marinating.

Anisakis Simplex Antigens in Fresh and Frozen-thawed Muscle of Anchovies in Vinegar

Marinated fish treatment using low pH to enlarge the storage life of fish as in anchovies in vinegar, does not kill Anisakis simplex larvae infesting fish muscle. To kill the larvae it is compulsory in many countries to freeze fish intended to be marinated raw, which prevents the consumer to be infested with the live larvae. However, it is not known if A. simplex antigens are released to the media after freezing and vinegar processing, which may cause allergic reaction to A. simplex sensitized consumers. Anchovy fillets were artificially infested with A. simplex L3, treated with a vinegar solution and chilled stored for 10 days. Infested frozen-thawed fillets were treated and stored in the same conditions. Viability of the larvae, SEM, immunoblotting and immunohistochemistry were performed on the treated fillets before and after pepsin treatment. Viability of the larvae was detected only in the chilled fillets; however, A. simplex antigens were detected in the chilled and in the frozen-thawed fillets even after pepsin treatment. This suggests that the consumption of anchovies in vinegar may be a potential hazard when ingested by sensitized consumers, even if freezing kills the larvae.

Allergenic Properties and Cuticle Microstructure of Anisakis simplex L3 after Freezing and Pepsin Digestion

This article examines the viability of and the alterations to the larval cuticle and the pattern of the antigens released when live or frozen Anisakis simplex larvae were treated with acid and pepsin. The results showed that freezing did not greatly alter the larva body. If ruptures were observed, the antigen release to the incubation media was not enhanced, and most of the antigenic content was retained inside the bodies of the larvae. The immunoblotting assay demonstrated that most of the antigens released, including the allergen Ani s 4, were resistant to pepsin. Freezing killed the larvae, but their survival was not compromised by acid treatment or pepsin digestion when kept chilled. All these findings support recommendations about freezing fish for consumption raw or undercooked to prevent human infection by A. simplex larvae. However, our data show that the antigenicity of the larvae is preserved after freezing and may explain why some sensitized patients develop symptoms after ingestion of infested frozen fish.

The parasite fauna of Arctogadus glacialis (Peters) (Gadidae) from western and eastern Greenland

In all 155 specimens of the high Arctic codfish Arctogadus glacialis examined for metazoan parasites, 55 specimens were from southern and northern Baffin Bay, western Greenland, and 100 specimens from north-eastern Greenland and Scoresby Sound. A total of 20 parasite taxa were recorded. A new myxozoan Gadimyxa arctica was found in southern Baffin Bay and Scoresby Sound. The gadid myxozoan Zschokkella hildae, the digeneans Gonocerca phycidis and Lecithaster gibbosus, the gill copepod Haemobaphes cyclopterina and third-stage larvae of the nematodes Anisakis simplex and Hysterothylacium aduncum were found in Scoresby Sound only. The digenean Hemiurus levinseni and third-stage larvae of the nematode Contracaecum sp. were found at all four stations. The nematodes Ascarophis spp. were found at three stations. The parasite fauna of A. glacialis from Scoresby Sound was very similar to that of 50 specimens of the closely related Boreogadus saida from the same area.

Ani s 1, the major allergen of Anisakis simplex: Purification by affinity chromatography and functional expression in Escherichia coli

Third stage larvae of the nematode Anisakis simplex often infect marine fish and invertebrates. When the larvae are ingested orally via seafood, they can cause IgE-mediated allergic reactions as well as anisakiasis. Of the known A. simplex allergens, Ani s 1 (Kunitz/bovine pancreatic trypsin inhibitor family protein) has been demonstrated to be a major allergen, being expected to be a useful tool for diagnosis of A. simplex allergy. For a diagnostic purpose, sufficient amounts of either natural Ani s 1 (nAni s 1) or recombinant Ani s 1 (rAni s 1) with an IgE-binding capacity should be stably supplied whenever needed. In this study, therefore, we first developed a simple and rapid purification method for Ani s 1 that is based on affinity chromatography using anti-Ani s 1 antibodies as ligands. The method was shown to produce nAni s 1 with a higher yield than the previously reported methods. Then, an attempt was made to express rAni s 1 in Escherichia coli as a His-tagged protein. rAni s 1 obtained as an inclusion body was solubilized in a solvent containing denaturing and reducing reagents and purified by nickel-chelate chromatography. Refolding of rAni s 1 was accomplished by dialysis in the presence of arginine, followed by that in the absence of arginine. Fluorescence ELISA and inhibition ELISA data revealed that rAni s 1 is IgE reactive enough to be used as a diagnostic tool.

The impact of carbofuran on acetylcholinesterase activity in Anisakis simplex larvae from Baltic herring

The aim of this study was to investigate the impact of carbofuran, a carbamate pesticide on the enzymatic activity of acetylcholinesterase (AChE) in the larvae of the herring nematode parasite Anisakis simplex. A. simplex larvae collected from herring were exposed to carbofuran in vivo at concentrations of 50, 100, 500 and 1000 μg/l, for 24, 48 and 72 h, at a temperature of 4 °C. Generalized Linear Models (GLM) were applied to analyze the relationship between AChE activity and carbofuran concentration, the time of exposure and the biological parameters of the host. The results indicate that A. simplex larvae have a high threshold of sensitivity to carbofuran. The average enzymatic activity was higher in parasites obtained from male hosts, when compared with female hosts. These data suggest that host sex-dependent biological processes may also influence AChE enzymatic activity in parasites.

Application of the PCR-sequence-specific primers for the discrimination among larval Anisakis simplex complex

The fish-borne zoonotic nematode, Anisakis simplex, is not a single specie but a complex composed of three sibling species, A. simplex sensu stricto, Anisakis pegreffii, and A. simplex C. Discrimination among these sibling species have been performed by polymerase chain reaction (PCR)-restriction fragment length polymorphism or sequencing analysis of the internal transcribed spacer (ITS) region of ribosomal DNA (rDNA). In the present study, PCR-sequence-specific primers were applied for the discrimination of these parasites. Based on the sequence differences among A. simplex complex at the ITS region of rDNA, forward primer ASF1 that is expected to be specific to A. pegreffii was newly developed. The specific fragment was amplified in only A. pegreffii by PCR with ASF1, but not quite in A. simplex s. str., Anisakis physeteris, Pseudoterranova decipiens, and Contracaecum osculatum. This result suggests that PCR using the forward primer ASF1 might be applicable for the discrimination of A. simplex complex.

TREHALOSE CATABOLISM ENZYMES IN L3 AND L4 LARVAE OF ANISAKIS SIMPLEX

The presence of trehalase and trehalose phosphorylase in L3 and L4 larvae of Anisakis simplex was demonstrated. The activity of trehalase and trehalose phosphorylase in L3 larvae was 6 and 10 times higher, respectively, than in L4 larvae. This suggests that trehalose metabolism is more important for L3 than LA larvae. Trehalases of L3 and L4 differ in their characteristics. The enzyme of L3 was present mainly in the lysosomes and cytosol, whereas in L4 the highest enzyme activity was measured in the lysosomal fraction. Trehalase activity was increased by 29% in L3 and 55% in L4 with the addition of Mg2+ (0.1 mmol). Tris inhibited trehalase in L3 larvae by 42% and in L4 by 25%. The enzymes differed in their reaction to EDTA, CaCl2, ZnCl2, and CH2ICOOH (all 0.1 mmol). High activity of trehalase from L3 larvae was measured within the pH range of 5.0 to 6.5, with an optimum pH of 6.1. The trehalase was a thermally tolerant enzyme from 25 C to 60 C. The enzyme lost half of its activity after preincubation without substrate above 75 C. The paper also discusses the similarities and differences in characteristics of trehalase from A. simplex larvae and presents the comparison to enzymes from other nematodes.

Parasite communities of eels Anguilla anguilla in freshwater and marine habitats in Iceland in comparison with other parasite communities of eels in Europe

Ninety-five eels from one marine and three freshwater localities in Iceland were examined for parasites. Twenty species were found, 12 from marine habitat, 12 from freshwater and 4 species were found in both habitats. These are: Eimeria anguillae, Chilodonella hexasticha, Trichodina fultoni, T. jadranica, Myxidium giardi, Myxobolus kotlani, two Zschokkella spp., Derogenes varicus, Deropristis inflata, Diplostonmum sp., Plagioporus angulatus, Podocotyle atomon, Anisakis simplex (larva), Eustrongylides sp. (larva), Hysterothylacium aduncum (larva), Raphidascaris acus (larval and adult stages), Bothriocephalus claviceps, Proteocephalus macrocephalus, and a pseudophyllidean larva. Thirteen of these species are new parasite records from Icelandic waters. The component community of marine eels was characterized by low diversity and a high dominance of a single species. Overall, seven species of helminths were observed, up to five different species occurring in an individual fish. The component community of the freshwater eels was species-poor with low diversity and relatively high dominance of single species. A between-sites difference in the freshwater eels was considerable; only Diplositonun sp. was found at more then one sampling site. Similar to previous studies, there is a total replacement of freshwater macroparasite species by marine ones in saline waters. But unlike research abroad in which species richness decreases with higher salinity, the marine eels in Iceland have considerably higher richness than the freshwater ones. The parasite communities of freshwater eels in Iceland are, in general species-poorer, less diverse and having higher Berger Parker (BP) dominance than other eel communities in Europe. Marine eels have on the other hand comparable species richness, are less diverse and with a high BP dominance.

Anisakis simplex: Analysis of expressed sequence tags (ESTs) of third-stage larva

This study analyzed the expressed sequence tags (ESTs) of the third-stage larvae of Anisakis simplex, in an attempt to gain further insight into its genomic expression patterns. An A. simplex cDNA library was constructed using the Uni-ZAP ™ XR expression vector. A total of 493 clones (insert DNA >400 bp) were sequenced out of 580 clones selected randomly from a cDNA library of the A. simplex third-stage larva. After BLAST search analyses, 154 (31.2%) ESTs were found to have very low similarity, or no match at all to any of the proteins and gene sequences in the published databases. Most matched clones (98 clones, 20.0%) were determined to be highly homologous with the genes or proteins of Caenorhabditis elegans. Ten (2.0%) ESTs matched the genes isolated from humans, and 21 (4.3%) ESTs matched with the previously reported A. simplex genes or proteins. Eighty-nine clones (18.0%) matched a total of 14 genera and 17 species of human parasites. These 339 ESTs identified could be grouped into 13 categories: allergens or antigens (4.1%), growth- and cell division-related proteins (3.2%), heat shock proteins or molecular chaperones (1.8%), membrane proteins (5.6%), metabolism-associated proteins (24.2%), mitochondrial proteins (9.4%), nuclear proteins (2.4%), proteases and protease inhibitors (3.5%), signal transduction proteins (2.4%), structural proteins (7.4%), transcription and translation machinery-associated proteins (20.1%), transporters and receptor proteins (3.8%), and other protein types (12.1%). The genetic information of Anisakis determined in this study might prove to be quite helpful in elucidating the pathogenetic mechanisms of anisakidosis, and might be useful in the development of therapeutic reagents specific to anisakidosis.

Données nouvelles sur l’anisakidose

Acute anisakiasis is generally due to the third-stage larvae of Anisakis simplex, and occasionally to other anisakidae. Human infection occurs through consumption of raw seafish, and especially herring, hake, black plaice and cod. Patients sensitized by prior consumption of parasitized fish develop, within a few hours, violent abdominal pain and an allergic reaction. Anisakis-induced urticaria is seen in about one in five cases. Preventive measures have reduced the number of cases. In France for example, the number of cases fell four-fold between 1977-1991 and 1992-2005. In 1990 Kasuya [1] reported chronic anisakiasis related to consumption of cooked parasitized fish. Seafish-induced urticaria might be an allergic response to Anisakis larval antigens rather than to the fish itself. Indeed, 11 patients with mackerel-related urticaria all had a positive reaction to Anisakis simplex larval antigen, while none reacted to mackerel antigen. A low-molecular-weight thermostable A. simplex allergen causes chronic urticaria, angioedema and even anaphylactoid reactions. Victims have a genetic predisposition (HLA class II alleles) that is uncommon in France and Germany but frequent in Japan. A number of cases have been observed in Spain, where fish is particularly popular. Immunoblotting shows cross-reactions between antigens of A. simplex and Toxocara canis, nematodes belonging to the same superfamily. At present, the only way to avoid contracting anisakiasis is not to eat raw or even cooked parasitized seafish.

Differences in the Allergic Response Induced by Live or Dead Anisakis Simplex Larvae in C3H/HeJ Mice

Differences in the Allergic Response Induced by Live or Dead Anisakis Simplex Larvae in C3H/HeJ Mice

New data on morphometry, feeding, and parasitic fauna of Atlantic spiny lumpsucker Eumicrotremus spinosus (Cyclopteridae) from the Barents Sea

Data on morphometric analysis, feeding, and parasitic fauna of the Atlantic spiny lumpsucker Eumicrotremus spinosus from the Northwestern Barents Sea are given. The amount of food in the whole digestive tract of fish in the evening (18.00–02.00) is high; the weight of food bolus averaged 1/9 of the weight of the fish without guts; the average index of fullness of the stomach was 1018‱. The small hyperiids Themisto abyssorum constituted the basis of food; Th. libellula, gammarides of the family Lysianassidae, and Gammarus wilkitzkii were consumed to a lesser degree. The pink shrimp Pandalus borealis and euphausiid Thysanoessa inermis are noted singly; the polychaetes of genus Nereis also serve as occasional food. Parasitic fauna of the Atlantic spiny lumpsucker is represented by the larvae of Anisakis simplex that are located on the liver parenchyma and pyloric appendages. The parasitic copepod Lernaeocera branchialis was found on the gills of one of the females.