Anisakis simplex: the high prevalence in Madrid (Spain) and its relation with fish consumption

Diagnostic approach to small-bowel wall thickening: Beyond Crohn's disease and cancer

Although small-bowel wall thickening is a common manifestation of Crohn's disease and tumors, many other entities can give rise to similar imaging findings. The small bowel is difficult to access by endoscopy, so radiologic imaging tests play an essential role in the diagnosis of conditions involving the small bowel. The main objectives of this paper are to explain the definition of small-bowel wall thickening, analyze the patterns of involvement seen in multidetector computed tomography (MDCT) with intravenous contrast administration, and provide an image-based review of the different causes of small-bowel wall thickening. The differential diagnosis must include many entities because wall thickening can result from immune-mediated, infectious, or vascular causes, as well as from toxicity and other lesser-known entities. As the imaging appearance of many of these conditions overlap, clinical and laboratory findings are necessary to support the imaging diagnosis.

Metagenomics Analysis Reveals an Extraordinary Inner Bacterial Diversity in Anisakids (Nematoda: Anisakidae) L3 Larvae

L3 larvae of anisakid nematodes are an important problem for the fisheries industry and pose a potential risk for human health by acting as infectious agents causing allergies and as potential vectors of pathogens and microrganisms. In spite of the close bacteria-nematode relationship very little is known of the anisakids microbiota. Fresh fish could be contaminated by bacteria vectored in the cuticle or in the intestine of anisakids when the L3 larvae migrate through the muscles. As a consequence, the bacterial inoculum will be spread, with potential effects on the quality of the fish, and possible clinical effects cannot be discarded. A total of 2,689,113 16S rRNA gene sequences from a total of 113 L3 individuals obtained from fish captured along the FAO 27 fishing area were studied. Bacteria were taxonomically characterized through 1803 representative operational taxonomic units (OTUs) sequences. Fourteen phyla, 31 classes, 52 orders, 129 families and 187 genera were unambiguously identified. We have found as part of microbiome an average of 123 OTUs per L3 individual. Diversity indices (Shannon and Simpson) indicate an extraordinary diversity of bacteria at an OTU level. There are clusters of anisakids individuals (samples) defined by the associated bacteria which, however, are not significantly related to fish hosts or anisakid taxa. This suggests that association or relationship among bacteria in anisakids, exists without the influence of fishes or nematodes. The lack of relationships with hosts of anisakids taxa has to be expressed by the association among bacterial OTUs or other taxonomical levels which range from OTUs to the phylum level. There are significant biological structural associations of microbiota in anisakid nematodes which manifest in clusters of bacteria ranging from phylum to genus level, which could also be an indicator of fish contamination or the geographic zone of fish capture. Actinobacteria, Aquificae, Firmicutes, and Proteobacteria are the phyla whose abundance value discriminate for defining such structures.

Effectiveness of Gutting Blue Whiting (Micromesistius poutassou, Risso, 1827), in Spanish Supermarkets as an Anisakidosis Safety Measure

Anisakidosis is a parasitic zoonotic disease which can cause gastroallergic reactions in humans. In 2010, the European Food Safety Agency estimated that approximately 20,000 cases of anisakiasis had been reported across the world, with Spain having the highest number of infections in Europe. The blue whiting (Micromesistius poutassou, Risso, 1827) is one of the most widely fished species worldwide and represents around 25% of the white fish eaten in Spain. The Spanish Food Safety Authority requires obligatory evisceration of certain fish species before commercialization, but not for blue whiting. Nevertheless, some supermarkets carry this out themselves to prevent human infections and negative customer reactions deriving from the presence of ascaridoid larvae. To assess the effectiveness of eviscerations at supermarkets, a total of 320 blue whiting specimens were examined. The risk of larval migration from the visceral cavity to the musculature in gutted and ungutted fish was also assessed. Our results showed a total prevalence (25%) of ascaridoids in fish gutted at the supermarket, and a direct relationship was found between the presence of larvae in the muscle and time until evisceration. In ungutted fish, the standard length and weight were higher for infected than for non-infected fish. Also, massive infections had a higher prevalence in these larger specimens, in which the viability of larvae was also high. Larval viability was not found to be affected by a 24-h refrigeration period. Anisakis was the most prevalent genus identified in the fish examined. The results indicate that gutting at the supermarket is not an effective method for the total removal of ascaridoid larvae and that additional safety measures are advisable.

Diagnostic approach to small-bowel wall thickening: beyond Crohn's disease and cancer

Although small-bowel wall thickening is a common manifestation of Crohn's disease and tumors, many other entities can give rise to similar imaging findings. The small bowel is difficult to access by endoscopy, so radiologic imaging tests play an essential role in the diagnosis of conditions involving the small bowel. The main objectives of this paper are to explain the definition of small-bowel wall thickening, analyze the patterns of involvement seen in multidetector computed tomography (MDCT) with intravenous contrast administration, and provide an image-based review of the different causes of small-bowel wall thickening. The differential diagnosis must include many entities because wall thickening can result from immune-mediated, infectious, or vascular causes, as well as from toxicity and other lesser-known entities. As the imaging appearance of many of these conditions overlap, clinical and laboratory findings are necessary to support the imaging diagnosis.

World-wide prevalence of Anisakis larvae in fish and its relationship to human allergic anisakiasis: a systematic review

The infective stage of Anisakidae nematodes responsible for allergic reactions in humans is found in a variety of edible fish and cephalopods. The identification of geographical regions that are high risk for infected seafood may help prevent allergic reactions in humans. Despite an abundance of published literature which has identified anisakid larvae in an array of edible seafood as well as scattered reports of human allergic anisakiasis, the relationship between the two has not been fully explored. Therefore, a systematic spatio-temporal study was conducted to determine the prevalence of Anisakis spp. in fish from January 2000 to August 2020 firstly to explore the relationship between fish infection and cases of allergic anisakiasis and secondly to use fish infection data to map potential allergic anisakiasis 'hot spots'. A systematic literature search for original English text articles was conducted through search engines, Web of Science, Scopus, PubMed, Science Direct and Google Scholar. Out of 3228 articles which describe anisakid infection in fish, 264 were used for data extraction. Of 904 articles describing allergic anisakiasis, 37 were used for data extraction. A qualitative summary of the extracted data was performed using equal interval method (ArcMap software) in order to compare the global distribution of Anisakis-infected fish. Of the 152-identified fish hosts, five families were most commonly infected with Anisakis spp. These included Lophiidae (86.9%), Trichiuridae (77.05%), Zeidae (70.9%), Merlucciidae (67.8%) and Gadidae (56.8%). The hot spot areas for allergic anisakiasis were North and northeast of Atlantic Ocean, southwest of USA, west of Mexico, south of Chile, east of Argentina, Norway, UK and west of Iceland (confidence 99%). The highest rate of allergic anisakiasis was in Portugal and Norway with the prevalence rate of 18.45-22.50%. Allergologists should consider allergic anisakiasis as a public health issue particularly in high-risk countries where high prevalences in fish have been demonstrated.

Analysis of Ani s 7 and Ani s 1 allergens as biomarkers of sensitization and allergy severity in human anisakiasis

The high frequency of infection by Anisakis simplex (A. simplex) has led to an increase in IgE sensitization, turning allergy to this parasite a relevant contemporary health problem. Improving the lack of conventional diagnosis test specificity is crucial to better understand these clinical scenarios. Specific IgE (sIgE) to A. simplex extract by ImmunoCAP (Anisakis-sIgE) was determined in sera from 403 blood donors (BD) from Cantabria (North of Spain) of which 51 subjects resulted sensitized. Among these latter, 47 were asymptomatic (sABD). The values of total IgE, prick-test, Anisakis-sIgE, and sIgE to Ani s 1 (anti-rAni s 1) and Ani s 7 (anti-rAni s 7) were compared between 46 sABD and 49 A. simplex allergic patients. The IgE seroprevalence by ImmunoCAP among BD was 12.65%. Allergic patients and sABD showed significant differences in all serum biomarkers evaluated. The area under the curve was assessed for Anisakis-sIgE (0.892), sIgE-rAni s 1 (0.672) and sIgE-rAni s 7 (0.668). After a severe reaction, significantly higher levels of Anisakis-sIgE and sIgE anti-rAni s 1 were detected. Determinations of sIgE by ImmunoCAP, Ani s 1 and Ani s 7 presented different sensitization patterns between allergic and asymptomatic individuals. The Ani s 1 allergen arises as a possible biomarker to detect patients at risk of suffering severe allergic reactions.

Urticaria and silent parasitism by Ascaridoidea: Component-resolved diagnosis reinforces the significance of this association

Urticaria remains a major problem in terms of aetiology, investigation, and management, and although parasitic diseases are considered potential causes, the absence of a consistent link between parasitic infections and skin allergy symptoms leads to the need for a deeper study of parameters that support this association. The objectives of this study were to analyse a possible relationship between parasitism by Ascarididae (Toxocara canis and Anisakis simplex) and the clinical expression of urticaria and to identify possible parasitic molecular markers for improving the diagnosis of unknown urticaria aetiology. The prevalence of Toxocara and Anisakis infestations was evaluated by measuring the levels of specific IgG (sIgG) and IgE (sIgE) antibodies against crude extracts and isolated components from whole larvae of Anisakis simplex (Ani s 1, Ani s 3 and Ani s 7) and Toxocara canis (TES-120, TES-70, TES-32 and TES-26) using immunologic and molecular diagnostic methods. A cross-sectional study was performed in a group of 400 individuals. The study group consisted of 95 patients diagnosed with urticaria (55 with chronic urticaria and 40 with acute urticaria). A control group consisted of 305 subjects without urticaria (182 diagnosed with respiratory allergy and 123 without allergy). Statistically significant differences were demonstrated in the seroprevalence of specific IgG and IgE antibodies between the urticaria patients and the healthy general population when isolated ascarid antigens were evaluated. The prevalence of IgG antibodies against Ani s 1, IgE antibodies against TES-120 and IgE antibodies against TES-70 were significantly different between the control individuals (healthy general population) and patients with urticaria. Moreover, the urticaria patient group demonstrated a higher seroprevalence of antibodies (sIgE and sIgG) against Anisakis simplex larva whole extract than the control group but just with statistically diferences when sIgE was evaluated. The presence of IgE and/or IgG antibodies against Ani s 3 (tropomyosin) can help to discriminate between patients with and without urticaria. Both ascarids seem to be associated with urticaria, although in our region, Anisakis seems to have greater involvement than Toxocara in this relationship. Molecular diagnostics can be used to associate urticaria with parasite infestations. Tropomyosin and Ani s 1 were the most relevant markers to demonstrate the association between urticaria and the most relevant Ascarididae parasites in our region.

Anisakis Sensitization in the Croatian fish processing workers: Behavioral instead of occupational risk factors?

We undertook the first study systematically evaluating the risk of Anisakis-sensitization in Croatian fish-processing workers and potential genetic susceptibility to anisakiasis. Anti-Anisakis IgE seroprevalence and risk factors for 600 employees of Croatian fish processing facilities and 466 blood donor controls, were assessed by indirect ELISA targeted with: recombinant Ani s 1 and Ani s 7 allergens, an Anisakis crude extract, the commercial ImmunoCAP kit, and questionnaires. Genetic susceptibility to anisakiasis was evaluated by genotypisation of human leukocytes alleles (HLA). Anti-Anisakis seropositive and a fraction of negative subjects were also assessed by ELISA and Western Blot (WB) for IgG seroprevalence to Trichinella spp. Overall, the observed anti-Anisakis seroprevalence inferred by indirect ELISA was significantly higher in fish processing workers (1.8%, 95% CI 0.9–3.3%) compared to the controls (0%, 0–0.8%). Seven out of 11 Ani s 1 and Ani s 7-positives and none of selected 65 negative sera, tested positive on whole-Anisakis extract (ImmunoCAP), whereas Anisakis crude extract ELISA detected 3.9% (2.4–6.0%) seropositives in fish processing workers, three (14%) of which showed IgE reactivity to milk proteins. The highest risk associated with Anisakis-sensitization among workers was fishing in the free time, rather than any of attributes related to the occupational exposure. Although no association was observed between anti-Anisakis seropositivity and wearing gloves or protective goggles, the majority of workers (92%) wore protective gloves, minimizing the risk for Anisakis sensitization via skin contact. Six HLA alleles within DRB1 gene were significantly associated with seropositivity under dominant, allelic or recessive models. All sera confirmed negative for anti-Trichinella spp. IgG. The study exhaustively covered almost all marine fish processing workers in Croatia, reflecting real-time Anisakis sensitization status within the industry, already under the influence of wide array of allergens.

Anisakiasis is a human disease caused by ingestion of live Anisakis spp. larvae by raw seafood. Fish processing and aquaculture workers (approximately 60 million people world-wide) are at occupational risk of becoming sensitized to Anisakis. This is the first study systematically evaluating the risk of Anisakis-sensitization in Croatian fish-processing workers and potential genetic susceptibility to anisakiasis in the analysed population. Observed seroprevalence was significantly higher in fish processing workers (1.8%) compared to the controls (0%). Surprisingly, the highest risk associated with Anisakis-sensitization among workers was fishing in their free time, rather than any of attributes related to the occupational exposure. While no association was observed between anti-Anisakis seropositivity and wearing gloves or protective goggles, the majority of workers (92%) wore protective gloves, minimizing the risk for Anisakis sensitization via skin contact. Additionally, seroprevalence to another important food-borne helminth, Trichinella spp. assessed in all Anisakis-positive subjects showed to be negative. Almost all marine fish processing workers in Croatia were part of this research, reflecting real-time Anisakis-sensitization status within the industry. This sets a baseline for the future tracking of sensitization in the sector already under the influence of wide array of allergens.

Epidemiological Scenario of Anisakidosis in Spain Based on Associated Hospitalizations: The Tip of the Iceberg

BACKGROUND

The risk of infection with Anisakis has been recognized for some time, but it is now emerging due to major awareness, better diagnostic techniques, and increasing preference for raw or lightly cooked food. Spain has the second-highest reported incidence after Japan, though the real anisakidosis burden is unknown because of the scarcity of epidemiological data. This study provides a 19-year review of anisakidosis-related hospitalizations describing epidemiological trends and patient characteristics.

METHODS

We performed a retrospective descriptive study using the Spanish Hospitalization Minimum Data Set from 1997 to 2015. Hospitalization rates were calculated and spatial distribution of cases and their temporal behavior were assessed. Clinical characteristics were described, including related codiagnoses and procedures.

RESULTS

A total of 2471 hospital discharges were identified. A continuous increasing trend was observed, with several peaks. Most affected communities were located in the northwest inland part of the country. Almost 54% of hospitalized patients were male, with a mean age of 51.3 years. Median length of stay was 5 days, and the hospitalization median cost around €2900. Fatal outcome occurred in 0.5%. Most frequent codiagnoses were digestive diseases, mainly intestinal obstruction. Urticaria, anaphylactic reaction, and angioneurotic edema were only recorded in 2.2%, 2.4%, and 1.2%, respectively.

CONCLUSIONS

Knowing that hospitalization is unusual in anisakidosis, we offer calculations of the real disease burden. Improving disease surveillance in parallel to disease control will be useful both in gaining extended disease knowledge and reducing morbidity and related costs.

Anisakis sensitization in different population groups and public health impact: A systematic review

Anisakis simplex spp. sensitization rates have increased worldwide, with a significant impact on health-care systems. To date, no clear-cut diagnostic criteria and laboratory algorithm have been established, so anisakiasis still represents an under-reported health problem whose clinical manifestations, when present, mimic the much more common allergic and digestive disorders. Aim of the study was to systematically review the available literature on the prevalence of sensitization against Anisakis in the general population and in specific population groups, taking into account the impact of the different available diagnostic techniques on the epidemiological data. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, relevant papers reporting Anisakis sensitization epidemiological data were found covering a period ranging from 1996 to February 2017. Overall, 41 studies comprising 31,701 participants from eleven countries were included in the qualitative synthesis. General asymptomatic population resulted sensitized to Anisakis in 0.4 to 27.4% of cases detected by means of indirect ELISA or ImmunoCAP specific IgE detection, and between 6.6% and 19.6% of the samples by Skin prick test (SPT). Occupationally exposed workers (fishermen, fishmongers and workers of fish-processing industries) documented specific IgE between 11.7% and 50% of cases, whereas SPT positivity ranged between 8% and 46.4%. Symptomatic allergic patients to any kind of allergen were found to be positive to Anisakis specific IgE detection between 0.0% (in children with mastocytosis) to 81.3% (among adults with shellfish allergy). Results highlighted that hypersensitivity prevalence estimates varied widely according to geographical area, characteristics of the population studied, diagnostic criteria and laboratory assays. Further studies are needed to overcome the documented misdiagnosis by improving the diagnostic approach and, consequently, providing more affordable estimates in order to address public health interventions on populations at high risk of exposure to Anisakis and to tailor health services related to specific groups.

Functional insights into the infective larval stage of Anisakis simplex s.s., Anisakis pegreffii and their hybrids based on gene expression patterns

BACKGROUND

Anisakis simplex sensu stricto and Anisakis pegreffii are sibling species of nematodes parasitic on marine mammals. Zoonotic human infection with third stage infective larvae causes anisakiasis, a debilitating and potentially fatal disease. These 2 species show evidence of hybridisation in geographical areas where they are sympatric. How the species and their hybrids differ is still poorly understood.

RESULTS

Third stage larvae of Anisakis simplex s.s., Anisakis pegreffii and hybrids were sampled from Merluccius merluccius (Teleosti) hosts captured in waters of the FAO 27 geographical area. Specimens of each species and hybrids were distinguished with a diagnostic genetic marker (ITS). RNA was extracted from pools of 10 individuals of each taxon. Transcriptomes were generated using Illumina RNA-Seq, and assembled de novo. A joint assembly (here called merged transcriptome) of all 3 samples was also generated. The inferred transcript sets were functionally annotated and compared globally and also on subsets of secreted proteins and putative allergen families. While intermediary metabolism appeared to be typical for nematodes in the 3 evaluated taxa, their transcriptomes present strong levels of differential expression and enrichment, mainly of transcripts related to metabolic pathways and gene ontologies associated to energy metabolism and other pathways, with significant presence of excreted/secreted proteins, most of them allergens. The allergome of the 2 species and their hybrids has also been thoroughly studied; at least 74 different allergen families were identified in the transcriptomes.

CONCLUSIONS

A. simplex s.s., A. pegreffi and their hybrids differ in gene expression patterns in the L3 stage. Strong parent-of-origin effects were observed: A. pegreffi alleles dominate in the expression patterns of hybrids albeit the latter, and A. pegreffii also display significant differences indicating that hybrids are intermediate biological entities among their parental species, and thus of outstanding interest in the study of speciation in nematodes. Analyses of differential expression based on genes coding for secreted proteins suggests that co-infections presents different repertoires of released protein to the host environment. Both species and their hybrids, share more allergen genes than previously thought and are likely to induce overlapping disease responses.

Anti-Anisakis sp. antibodies in serum of patients with sepsis and their relationship with γδ T cells and disease severity

Immunosuppression in sepsis reduces both αβ and γδ T cell subsets. Anisakis sp. is a parasitic nematode with a high prevalence in Spain. Previous contact with the parasite is related to a decrease in γδ T cells. Anti-Anisakis antibodies were measured and related to αβ and γδ T cells in 114 septic patients versus 97 healthy controls. Significant differences were seen with respect to the groups with severe sepsis and septic shock where lower anti-Anisakis levels were observed. A similar decrease appeared in the case of specific IgM with significant differences between the groups of control/uncomplicated sepsis versus severe sepsis and septic shock. These differences were also apparent in the case of specific IgA. The lowest IgE levels were detected in the septic shock group. Anti-Anisakis IgG levels significantly increased in septic shock groups compared with the controls. We observed positive correlations among anti-Anisakis IgA levels and all γδ T cell subsets. There were negative correlations among IgA levels and APACHE and SOFA indices. Greater contact with the parasite (IgG) was directly related with septic shock, inflammation and markers of sepsis severity. A lack of protection in the mucosa (IgA and γδ T cells) was associated with the disease severity.

Geographic and host size variations as indicators of Anisakis pegreffii infection in European pilchard (Sardina pilchardus) from the Mediterranean Sea: Food safety implications

European pilchards are traditionally eaten marinated or salted in the Mediterranean countries often without thermal processing or gutting due to small size. Since ingestion of live third stage Anisakis larvae represents a causing agent in the onset of anisakiasis, the aim of our study was to assess prevalence and intensity of Anisakis infection in European pilchards originating from different Mediterranean regions in a three-year sampling period (2013-2015). A total of 1564 specimens of European pilchard collected from two geographically distinct sampling regions (western Mediterranean and Adriatic Sea) were examined using the UV-Press method, which utilises the fluorescence of frozen anisakids in flattened and subsequently frozen fillets and viscera. A subsample of 67 isolated larvae was identified as A. pegreffii by diagnostic allozyme markers and sequence analyses of the mtDNA cox2 locus. The overall prevalence in pilchards was 12.2% (range 0-44.9% for different sampling points) and mean intensity 1.8. More importantly, we have observed an overall larval prevalence of 1.5% in fillets. The highest prevalence (44.9%) was recorded in pilchards caught in western parts of the Mediterranean. As fish host size was a significant predictor of parasite abundance, it should be highlighted that these pilchards were also the largest (mean total length 173.2mm); on average >2cm larger than the rest of the samples. Other isolated nematode species included Hysterothylacium sp. in viscera, showing almost a double of A. pegreffii prevalence, 20.1%. In summary, our study demonstrates that the presence of A. pegreffii in European pilchards from the Mediterranean Sea is highly influenced by both geographic and host size variation. This implies that, before future risk management measures are developed, these variables should be assessed in order to minimize public health concerns.

Excretory/secretory products of anisakid nematodes: biological and pathological roles

Parasites from the family Anisakidae are widely distributed in marine fish populations worldwide and mainly nematodes of the three genera Anisakis, Pseudoterranova and Contracaecum have attracted attention due to their pathogenicity in humans. Their life cycles include invertebrates and fish as intermediate or transport hosts and mammals or birds as final hosts. Human consumption of raw or underprocessed seafood containing third stage larvae of anisakid parasites may elicit a gastrointestinal disease (anisakidosis) and allergic responses. Excretory and secretory (ES) compounds produced by the parasites are assumed to be key players in clinical manifestation of the disease in humans, but the molecules are likely to play a general biological role in invertebrates and lower vertebrates as well. ES products have several functions during infection, e.g. penetration of host tissues and evasion of host immune responses, but are at the same time known to elicit immune responses (including antibody production) both in fish and mammals. ES proteins from anisakid nematodes, in particular Anisakis simplex, are currently applied for diagnostic purposes but recent evidence suggests that they also may have a therapeutic potential in immune-related diseases.

Determination of Anti-Anisakis Simplex Antibodies and Relationship with αβ and γδ Lymphocyte Subpopulations in Patients with Crohn's Disease

BACKGROUND

The etiology of Crohn's disease (CD) is still unknown although new theories are based on defects in innate immunity. We have previously shown a decrease in γδ T cells in CD patients. Previous studies have shown a high prevalence of anti-A. simplex immunoglobulins in CD patients. The diminution of γδ T cells in the peripheral blood and intestinal mucosa of CD patients may create a state of immunosuppression that would facilitate A. simplex infection.

AIMS

To study the antibody responses to Anisakis antigens in Crohn's disease patients and its relationship with αβ and γδ T cell subsets.

METHODS

We recruited 81 CD patients and 81 healthy controls. αβ and γδ T cell subsets and anti-A. simplex antibodies were measured.

RESULTS

Levels of anti-A. simplex IgG and IgM were significantly increased in CD patients. Almost 20% of CD patients were positive for IgG and IgM anti-A. simplex versus only 3.7 and 2.5%, respectively, in normal subjects. However, lower specific IgA levels were observed in the group of CD patients versus healthy subjects. We found an association between CD3 + CD8 + γδ subset and IgM anti-A. simplex levels. In ileal cases and stricturing behavior of CD, we observed the highest levels of specific antibodies with the exception of anti-A. simplex IgA.

CONCLUSIONS

The relationship of specific antibodies with a γδ T cell deficiency makes these cell candidates to play a role in the immune response against Anisakis. In addition, anti-Anisakis antibodies could be considered as markers of risk of progression in CD.

Assessing the risk of an emerging zoonosis of worldwide concern: anisakiasis

Anisakiasis is an emerging zoonosis caused by the fish parasitic nematode Anisakis. Spain appears to have the highest reported incidence in Europe and marinated anchovies are recognised as the main food vehicle. Using data on fishery landings, fish infection rates and consumption habits of the Spanish population from questionnaires, we developed a quantitative risk assessment (QRA) model for the anchovy value chain. Spaniards were estimated to consume on average 0.66 Anisakis per untreated (non-frozen) raw or marinated anchovy meal. A dose-response relationship was generated and the probability of anisakiasis was calculated to be 9.56 × 10-5 per meal, and the number of annual anisakiasis cases requiring medical attention was predicted between 7,700 and 8,320. Monte Carlo simulations estimated post-mortem migration of Anisakis from viscera to flesh increases the disease burden by >1000% whilst an education campaign to freeze anchovy before consumption may reduce cases by 80%. However, most of the questionnaire respondents who ate untreated meals knew how to prevent Anisakis infection. The QRA suggests that previously reported figures of 500 anisakiasis per year in Europe is a considerable underestimate. The QRA tool can be used by policy makers and informs industry, health professionals and consumers about this underdiagnosed zoonosis.

Anti-Anisakis sp. antibodies in serum of healthy subjects. Relationship with αβ and γδ T cells

Anisakiosis is nowadays one of the nematodoses more prevalent in Spain, with rates that oscillate between 0.43% in Galicia (N.W. Spain), and 15.7% and 22.1% in inland and southern regions, respectively. Likewise, it has been proved that Anisakis larvae have developed mechanisms to modulate the dichotomy of the host immune response for their own benefit. The experimental hypothesis of the present study was that Anisakis sp. larval products can be mediators of immune suppression and induce changes on the populations of αβ+ and γδ+ T cells. In the present study we determined the levels of anti-Anisakis antibodies in the serum of healthy people, and their relationship with the B and T cell subsets. Levels of anti-Anisakis antibodies (Ig's, IgG, IgM, IgA and IgE) were measured by ELISA, while B and T cell subsets were studied by flow cytometry. Cells were labelled with monoclonal antibodies against CD45, CD4, CD8, CD56, CD3, CD19, TCRαβ and TCRγδ. All the specific isotypes studied were negatively correlated with NKT cell rates with the exception of IgG. A previous contact with Anisakis was related to a decrease in CD56+αβ+ and all γδ+ T cell subsets. The CD3+γδ+ population was lower in the group of subjects that showed IgA anti-Anisakis. We observed an inverse correlation among αβ-γδ NKT cells and anti-Anisakis sp. antibodies. CD3+CD56+ cells showed a significant decrease in the group of anti-Anisakis positive subjects. This fact was especially significant with CD3+CD56+γδ+ cells in the case of the anti-Anisakis IgA positive group.

Prevalence and Mean Intensity of Anisakidae Parasite in Seafood Caught in the Mediterranean Sea Focusing on Fish Species at Risk of Being Raw-consumed. A Meta Analysis and Systematic Review

OBJECTIVE

To assess the prevalence and mean intensity of anisakids in seafood caught in the Mediterranean Sea, focusing on fish species at risk of being raw-consumed.

DESIGN

Systematic review and meta-analysis of studies published from 1960-2012.

STUDY SELECTION

Main criteria for the inclusion of studies were as follows: Findings of anisakid larvae, in both muscles and viscera; fish species for human consumption caught in the Mediterranean Sea; prevalence and mean intensity data for each species; and sample size equal to or more than 40 fishes.

RESULTS

Twelve studies were identified. Among these, four studies considered the following three fish species that are often consumed raw or preserved lightly, or not cooked thoroughly: anchovy, pilchard, and Atlantic mackerel.

DATA SYNTHESIS

All pooled analyses were based on the random-effect model. Anisakids prevalence in fish muscle was 0.64% (P < 0.0001), in viscera it was 1.34% (P < 0.0001), and overall prevalence was 0.95% (P < 0.0001). Mean intensity in muscle was 2.31 (P = 0.0083), in viscera it was 1.55 (P = 0.0174), and overall it was 1.81 (P < 0.0005). Heterogeneity indices (I(2)) were significantly high with the exception of viscera mean intensity.

CONCLUSIONS

Anchovy, pilchard, and Atlantic mackerel have a low prevalence and mean intensity of anisakidae larvae in both viscera and muscles. Mean Intensity was also low.

A case report of Anisakis pegreffii (Nematoda, Anisakidae) identified from archival paraffin sections of a Croatian patient

BACKGROUND

This is the first report of anisakiasis in a Croatian patient, evidenced from an archival paraffin-embedded and hematoxylin-eosin stained tissue section. Anisakiasis has been only suspected in the country based on previously detected anti-Anisakis IgE seroprevalence in the healthy coastal population, as well as an acute case where pathohistological and serological findings suggested the diseases, but the migrating larva has not been retrieved.

CASE PRESENTATION

Seventy years-old female, operated in 1998 for pulmonary carcinoma, was admitted to the General hospital Šibenik, Croatia in 2003, because of gastric pain and nausea that lasted for couple of days. She was showing good general condition, full mobility and lucidity, subfebrile status. Abdominal palpation inferred acute pain in paraumbilical and ileocecal region. Exploratory right pararectal laparotomy revealed a hardened, 5 cm-long structure, located intraluminally in the sigmoid colon, not perforating colon serosa. The process has been dissected and sent for patohistological diagnosis. Results showed a 2 mm-long whitish nematode spiralised in muscular layer of colon mucosa surrounded by granulomatous inflammation.

CONCLUSION

After genomic DNA isolation of the nematode from the histological section, and amplification at the mitochondrial cytochrome oxidase 2 locus, etiological agent has been identified as Anisakis pegreffii. Used methodology suggests that screening of archival suspicious sections is feasible in order to study epidemiology of this zoonotic disease poorly recognised in Croatia.

Helminthosis and eosinophilia in Spain (1990-2015)

The finding of blood eosinophilia in a patient is a relatively frequent reason to refer him/her to a Clinical Department of Infectious Diseases. The doctor usually intends to rule out a parasitic disease in the autochthonous population, travelers or immigrants. It is uncommon for an eosinophilia to be produced by protozoa infection, whereas helminth parasites are more frequently associated with an increase of eosinophil counts in the infected patient. Eosinophilia can be the only abnormal finding, or it could be part of more complex clinical manifestations suffered by the patient. Furthermore, many, but not all, helminth infections are associated with eosinophilia, and the eosinophil level (low, high) differs according to parasite stages, helminth species, and worm co-infections. The purpose of the present article is to carry out a systematic review of cases and case series on helminth infections and eosinophilia reported in Spain from 1990 to 2015, making a distinction between autochthonous and imported (immigrants and travelers) cases, and studying their relationship with immunodepression situations.

Diamine oxidase levels in different chronic urticaria phenotypes

BACKGROUND

Diamine oxidase (DAO) is a polyamine-degrading enzyme also implicated in histamine metabolism. Chronic urticaria (CU) has a wide spectrum of clinical presentations and causes. Anisakis sensitisation associated chronic urticaria (CU+) has been characterised as a phenotype with different clinical and immunological characteristics and possibly associated with previous acute parasitism. We aimed to analyse serum DAO levels in different CU phenotypes. We further analysed the possible association of DAO with fish eating habits.

METHODS

We studied 35 CU+ patients and 39 non-sensitised CU patients (CU-) as well as 19 controls. We analysed fish-eating frequency as well as fish intake associated exacerbation of CU (FIAE) or gastro-intestinal complaints (GI). DAO levels were further analysed with respect to lymphoproliferative responses, cytokine and specific IgE production.

RESULTS

DAO levels were not different between CU and controls, but were significantly higher in CU+ than in CU-. CU+ patients with FIAE had lower DAO levels, but no differences were detected in patients with GI. DAO levels correlated positively with oily and canned fish consumption in CU-. In CU+, DAO levels correlated positively with specific Anisakis IgE, percentages of proliferation in Anisakis stimulated peripheral blood lymphocytes, serum IL-2 and IL-6, but correlated negatively with mitogen stimulated TGF-β in supernatants.

CONCLUSIONS

DAO levels in CU depend on fish-eating habits and in CU+ on the amount of specific IgE production. In the CU+ phenotype, lower levels of DAO predispose to urticaria exacerbation after fish intake, probably due to a relative insufficient enteric availability of this enzyme.

Prevalence of bacteria and absence of anisakid parasites in raw and prepared fish and seafood dishes in Spanish restaurants

This study evaluated the presence of bacteria and anisakid parasites in 45 samples of raw anchovies in vinegar, a dish widely eaten in Spain, and in 227 samples of cooked fish and cephalopods served in Spanish food service establishments. Our analysis showed that, according to European and Spanish regulation, 14 to 30% of the prepared fish and cephalopod dishes exceeded the maximum allowable level for mesophilic aerobic counts, and 10 to 40% of these samples exceeded the allowable levels for Enterobacteriaceae. None of the studied samples showed evidence of anisakid parasites, Escherichia coli, Staphylococcus aureus, Salmonella, or Listeria monocytogenes. These results indicate that application of hazard analysis and critical control points, food safety training courses, and routine inspections in compliance with current European and Spanish legislation help protect consumer health.

Fishing area and fish size as risk factors of Anisakis infection in sardines (Sardina pilchardus) from Iberian waters, southwestern Europe

The sardine (Sardina pilchardus) is a fish commonly consumed and appreciated in many countries, although they are more likely to be eaten fresh in western Mediterranean countries such as Spain, Portugal, France or Italy. A molecular epidemiological survey of sardines from 5 fishing areas of the Spanish Mediterranean (Málaga, southern Spain) and Atlantic coasts (southern: Cádiz and Isla Cristina; northern: A Coruña and Ondarroa) was carried out to determine the presence of Anisakis spp. larvae. The highest prevalence of these larvae was observed in fish from A Coruña (28.3%), followed by Ondarroa (5%) and Cádiz (2.5%). No Anisakis larvae were found in fish from Málaga and Isla Cristina. Three Anisakis genotypes were identified: Anisakis simplex sensu stricto, Anisakis pegreffii and a hybrid genotype between these two species. A. pegreffii was the most prevalent species in A Coruña (71% of larvae). Only three Anisakis larvae (9% collected larvae) were located in the musculature of sardines: two were identified as A. pegreffii while the other was a hybrid genotype. Sardine infection was associated with fishing area and fish length/weight (length and weight were strongly correlated; Pearson's correlation 0.82; p<0.001). Risk factor multivariate analysis showed that the risk of infection increases 1.6 times for every additional cm in the length of the sardines from the same fishing area. Comparison of fish of equal length showed that in sardines from A Coruña the risk of parasitization is 11.5 times higher than in those from other fishing areas. Although the risk of infection by Anisakis through consumption of sardines is generally low due to the low epidemiological parameter values (prevalence 10%, mean intensity 1.7 (range 1-5) and mean abundance 0.17), as larger fish are more heavily parasitized, there is an increased risk of infection by Anisakis through consumption of large sardines which are raw or have undergone insufficient treatment (undercooked, smoked, marinated, salted, pickled, freezing,…).

An extended study of seroprevalence of anti-Anisakis simplex IgE antibodies in Norwegian blood donors

During the last decade, cases of the fish parasite Anisakis simplex infection and allergy in human have increased in countries with high fish consumption. Our aim was to perform an extended seroprevalence study of anti-IgE antibodies against this parasite in Norway, one of the high fish-consuming countries. At the Department of Immunology and Transfusion Medicine and the Laboratory of Clinical Biochemistry, Haukeland University Hospital, Bergen, Norway, two main groups of anonymized serum samples were collected; the first (n = 993) from recently recruited blood donors (designated 'BDO') and the second (n = 414) from patient with total IgE levels ≥1000 kU/l (designated 'IGE+'). The sera were analysed by the ImmunoCAP(®) method for total IgE and IgE antibodies against A. simplex, house dust mite (HDM), shrimp, cod, crab, brine shrimp and shrimp tropomyosin. The A. simplex positive sera were further tested by an enzyme-linked immunosorbent assay (ELISA) method, which uses 2 recombinant (r) major allergens, rAni s 1 and rAni s 7 as target antigens. SDS-PAGE and Western immunoblotting analyses were also performed. Whereas the prevalences by ImmunoCAP(®) were 0.4% and 16.2% in the BDO and IGE+ groups, respectively, analyses with recombinant allergens showed only 0.0% and 0.2%. Cross-reactivity and immunoblotting analyses suggested that most of the ImmunoCAP(®) positive sera were probably false-positive due to cross-sensitization to shrimp and HDM. However, positivity due to other A. simplex antigens should also be considered. Compared with other high fish-consuming countries, we observed a very low seroprevalence of anti-Anisakis IgE antibodies in a Norwegian population.

Clinical characteristics of gastroallergic anisakiasis and diagnostic implications of immunologic tests

Purpose

Recent studies have used the term "gastroallergic anisakiasis" to describe incidental gastrointestinal infection with Anisakis spp. larvae, proposed as a causative agent of food hypersensitivity. However, it is unknown whether this condition represents an independent disease entity distinguishable from acute gastric anisakiasis. To better understand the role of the allergic response in Anisakis infections we examined the clinical and immunological implications of Anisakis-specific IgE.

Methods

A prospective study was performed in a geographic region where the consumption of raw seafood is common. Case subjects who had been clinically diagnosed with gastroallergic anisakiasis were selected, along with controls who frequently ate raw seafood but had never experienced gastroallergic anisakiasis-like symptoms. Clinical and immunological features were compared based on atopic status, sensitization rates to Anisakis, and serum titer of Anisakis-specific IgE.

Results

Seventeen case subjects and 135 controls were included in this study. The case subjects had experienced gastrointestinal symptoms after raw seafood ingestion, along with additional mucocutaneous, respiratory, or multisystemic symptoms. Case subjects were significantly sensitized to Anisakis excretory-secretory product and crude extract compared with controls (76.5% vs 19.3%, P<0.001, and 88.2% vs 30.3%, P<0.001, respectively). Anisakis-specific serum IgE titers were also significantly higher in case subjects than in controls. Both the results of skin prick tests and elevated Anisakis-specific IgE titers (>17.5 kU/L) were found to be reliable indicators for the diagnosis of gastroallergic anisakiasis.

Conclusions

Among patients presenting acute gastric anisakiasis-like symptoms, a diagnosis of gastroallergic anisakiasis may be strongly supported by a high Anisakis-specific IgE titer.

Anti-Anisakis IgE seroprevalence in the healthy Croatian coastal population and associated risk factors

BACKGROUND

The main objective of the study was to determine the degree of sensitization to Anisakis spp. antigens in healthy coastal population of Dalmatia given the high thermally unprocessed fish intake rate present in this area, suggested as a significant risk factor for anisakiasis. We performed a monocenter, cross-sectional pilot study stratified by geographic area of residence, conducted at the County secondary healthcare provider Medicine-biochemical Laboratory in Split (Croatia), from November 2010 till December 2011, on 500 unpaid volunteer subjects undergoing routine blood analysis and belonging to the south coast of the Adriatic Sea.

METHODOLOGY/PRINCIPAL FINDINGS

We studied the IgE seroprevalence to Anisakis spp. Ani s l and Ani s 7 allergens by indirect ELISA in healthy subjects, which were selected at random in the region of Dalmatia (Southern Croatia), among islands, coastal urban and inland rural populations. In order to detect possible cross-reactivity to other human helminthes, serum samples were tested also for the presence of IgG antibodies to Ascaris lumbricoides and Toxocara canis. The overall and coastal Anisakis seroprevalences for the sampled population were 2% and 2.5%, respectively. The logistic univariate regression analysis confirmed that regarding anti-Anisakis IgE seroprevalence, raw fish intake, daily fish intake, homemade origin of fish dish and occupational contact (professional, artisanal or hobby contact with fishery or fish industry) were risk factors associated to Anisakis spp. sensitization, but neither of the variables was exclusive for a particular seropositive population. Also, a significant difference was observed between seropositive and seronegative subjects that had stated allergy or symptoms associated with allergy (atopic dermatitis, asthma or rhinitis) in their previous history.

CONCLUSIONS/SIGNIFICANCE

Being the first in Croatia, our study underlines the necessity of incorporating Anisakis spp. allergens in routine hypersensitivity testing of coastal population.

Ecology and genetic structure of zoonotic Anisakis spp. from adriatic commercial fish species

Consumption of raw or thermally inadequately treated fishery products represents a public health risk, with the possibility of propagation of live Anisakis larvae, the causative agent of the zoonotic disease anisakidosis, or anisakiasis. We investigated the population dynamics of Anisakis spp. in commercially important fish-anchovies (Anisakis), sardines (Sardina pilchardus), European hake (Merluccius merluccius), whiting (Merlangius merlangus), chub mackerel (Scomber japonicus), and Atlantic bluefin tuna (Thunnus thynnus)-captured in the main Adriatic Sea fishing ground. We observed a significant difference in the numbers of parasite larvae (1 to 32) in individual hosts and between species, with most fish showing high or very high Anisakis population indices. Phylogenetic analysis confirmed that commercial fish in the Adriatic Sea are parasitized by Anisakis pegreffii (95.95%) and Anisakis simplex sensu stricto (4.05%). The genetic structure of A. pegreffii in demersal, pelagic, and top predator hosts was unstructured, and the highest frequency of haplotype sharing (n = 10) was between demersal and pelagic fish.

Immunogenic activity of the fish tapeworm Pterobothrium heteracanthum (Trypanorhyncha: Pterobothriidae) in BALB/c mice

The aim of this study was to verify the immunogenicity of Pterobothrium heteracanthum (Cestoda: Trypanorhyncha) crude protein extract (PH-CPE) in BALB/c mice. The parasites were obtained from Micropogonias furnieri (Osteichthyes: Sciaenidae). Groups of six mice were each immunized with 10, 50 or 100 μg of PH-CPE, on days 0 and 35. Both specific IgG and IgE responses were developed after immunization. The immunoblot assay revealed that specific IgG recognizes PH-CPE proteins with two molecular weight ranges, 60-75 and 30-40 kDa, and that IgE recognizes larger proteins over 120 kDa. This appears to be the first report on the immunogenicity of metacestodes within the Pterobothriidae and that PH-CPE is a potential inducer of a specific IgE response.

Different fish-eating habits and cytokine production in chronic urticaria with and without sensitization against the fish-parasite Anisakis simplex

BACKGROUND

Anisakis simplex sensitization has been associated with acute, but also with chronic urticaria. The objective of this study is to characterize chronic urticaria with (CU+) and without sensitization (CU-) against the ubiquitous fish parasite A. simplex in a transversal and longitudinal evaluation.

METHODS

16 CU+ and 22 CU- patients were included and assessed for Urticaria activity score (UAS), fish-eating habits by standardized questionnaire and cytokine production (assessed by flow cytometric bead-based array) of peripheral blood mononuclear cells after stimulation with A. simplex extract or Concanavalin A (Con A). Patients were randomly put on a fish-free diet for three months and UAS, as well as cytokine production were again assessed. A difference of ≥1 in UAS was defined as improvement.

RESULTS

There was no difference in UAS in both groups. Anisakis induced IL-2, IL-4 and IFN-γ production was higher in CU+. Con A induced IL-6 and IL-10 production was higher in CU+. CU+ was associated with higher total fish intake, whereas CU- was associated with oily fish intake. The correlation of UAS was positive with oily fish, but negative with total fish intake. There was a better UAS-based prognosis in CU+ without diet. Improvement was associated with higher Con A induced IL-10/IFN-γ as well as IL-10/IL-6 ratios. Further, previous higher oily fish intake was associated with improvement.

CONCLUSIONS

Our data confirm the different clinical and immunological phenotype of CU+. Our results show a complex relationship between fish-eating habits, cytokine production and prognosis, which could have important consequences in dietary advice in patients with CU. When encountering A. simplex sensitization, patients should not be automatically put on a diet without fish in order to reduce contact with A. simplex products.

Histology as a valid and reliable tool to differentiate fresh from frozen-thawed fish

Selling fish products as fresh when they have actually been frozen and thawed is a common fraudulent practice in seafood retailing. Unlike fish products frozen to protect them against degenerative changes during transportation and to extend the product's storage life, fish intended for raw consumption in European countries must be previously frozen at -20° C for at least 24 h to kill parasites. The aim of this study was to use histological analysis to distinguish between fresh and frozen-thawed fish and to evaluate this method for use as a routine screening technique in compliance with the requirements of European Commission Regulation No. 882/2004 on official food and feed controls. Method performance (i.e., accuracy and precision) was evaluated on tissue samples from three common Mediterranean fish species; the evaluation was subsequently extended to include samples from 35 fish species in a second experiment to test for method robustness. Method accuracy was tested by comparing histological results against a "gold standard" obtained from the analysis of frozen and unfrozen fish samples prepared for the study. Method precision was evaluated according to interrater agreement (i.e., three laboratories with expertise in histopathology in the first experiment and three expert analysts in the second experiment) by estimating Cohen's kappa (and corresponding 95 % confidence intervals) for each pair of laboratories and experts and the combined Cohen's kappa for all three experts and laboratories. The observed interrater agreement among the three laboratories and the three experts indicated high levels of method accuracy and precision (high sensitivity and specificity) and method reproducibility. Our results suggest that histology is a rapid, simple, and highly accurate method for distinguishing between fresh and frozen-thawed fish, regardless of the fish species analyzed.

The effect of anti-Anisakis simplexantibody levels on C3 and C4 complement components in human sera

Previously, anin vitroeffect was observed on the complement system not only of the excretory-secretory products but also of somatic antigens from L3Anisakis simplexlarvae. In the present work the effect of anti-A. simplexspecific antibodies on C3 and C4 levels in human sera was investigated. Up to 309 samples of sera were tested to determine levels of C3 and C4 and anti-A. simplexantibodies, including immunoglobulins IgG, IgM, IgA and IgE. Significant differences were observed between levels of C3 and C4 and all immunoglobulins except for IgE. In the case of immunoglobulins, the probability that an anti-A. simplexpositive subject has a C3 deficiency was 3.8 times higher than a subject without specific antibodies. In conclusion, an association between elevated levels of anti-A. simplexantibodies and C3 and C4 deficiency was demonstrated.

IgE sensitization to the fish parasite Anisakis simplex in a Norwegian population: a pilot study

The reports on fish parasite Anisakis simplex allergy have increased in countries with high fish consumption in the last decade. In Norway, a high consumption country, the prevalence of immunoglobulin E (IgE) sensitization to A. simplex was still unknown. Thus, our objective was to investigate the sensitization prevalence in this country. At the Haukeland University Hospital, Bergen, Norway, two main groups of surplus serum samples were collected: one from newly recruited blood donors (BDO) and the other from the Allergy laboratory (ALL) after analysing IgE and IgE antibodies. The latter was divided into three series: one containing unsorted sera and two sorted by either Phadiatop(®) ≥0.35 kU(A)/l or total IgE ≥1000 kU/l. The sera were analysed for total IgE and IgE antibodies against A. simplex, shrimp, house dust mite (HDM), cod and cross-reactive carbohydrates (CCDs). The prevalence of IgE sensitization to A. simplex was 2.0%, 2.2% and 6.6% in BDO, the unsorted and Phadiatop(®) positive serum groups, respectively. A considerable degree of cross-sensitization to shrimp and HDM is further suggested. Unspecific binding because of high total IgE or by binding to CCDs seemed to play a minor role. The prevalence of IgE sensitization to A. simplex appears to be lower in a Norwegian population than in other high fish-consuming countries, but might still be overestimated owing to cross-sensitization.

Ani s 1 and Ani s 7 recombinant allergens are able to differentiate distinct Anisakis simplex-associated allergic clinical disorders

Diagnosis in gastro-allergic anisakiasis (GAA) is straightforward, when clinical history is combined with further allergological evaluation of specific IgE by means of skin prick test and serum specific IgE. In Anisakis simplex sensitisation associated chronic urticaria (CU+), clinical evaluation of possible previous parasitism is difficult, and positive serum specific IgE could be due to cross-reactivity or other unknown factors. In this study, we evaluated the association between IgE seropositivity to the recombinant allergens Ani s 1 and Ani s 7 and several A. simplex-associated allergic disorders. Twenty-eight patients with GAA and 40 patients with CU+ were studied and their IgE responses were compared with a control group composed of patients with chronic urticaria not sensitized to A. simplex (CU-) according to the skin prick test, as well as a group of 15 healthy subjects not referring urticaria or currently A. simplex associated symptoms. 82.1% of GAA patients and 42.5% of CU+ patients were positive for Ani s 1 (P < 0.001), while the Ani s 7 allergen was recognized by 92.9 and 92.5% of sera from patients with GAA and CU+, respectively. The combined positivity obtained for both allergens reached 100% in GAA, and 95% in CU+. IgE determinations to Ani s 1 and Ani s 7 allergens are useful to diagnose the Anisakis infections and to differentiate among several A. simplex-associated allergic disorders. The IgE responses to Ani s 1 are mainly associated with GAA, while this molecule cannot be considered a major allergen in CU+ patients.

Prevalence of sensitization to Anisakis simplex among professionally exposed populations in Sicily

Anisakis simplex (AS) is a cause of allergic sensitization and potential occupational risk is suggested in fishermen and workers assigned to fish processing and sale. A cross-sectional study was conducted in order to assess possible health effects of occupational exposure to AS in workers recruited from western Sicily fisheries sector. Social, demographic, and occupation-related data were collected. Serum total immunoglobulin E (IgE) and specific IgE levels to AS (threshold >0.35 kU/L) were determined by an fluoroimmunoassay technique. Ninety-four subjects with potential occupational exposure (fishmongers, fishermen, fish industry employees) were recruited. Specific AS IgEs were detected in 20.2% of the study population. AS IgE seroprevalence was elevated 6.7-fold (p = .03) among fishermen/sailors compared with fish industry workers. The study suggested the importance to adopt specific prevention strategies against exposure to AS in the occupational setting.

Anisakis hypersensitivity in Italy: prevalence and clinical features: a multicenter study

BACKGROUND

Anisakis simplex (As), a parasite in fish, is able to sensitize humans via the alimentary tract. The prevalence of hypersensitivity and allergy to As outside the Iberian peninsula has not been investigated so far. We investigated Anisakis hypersensitivity in different areas of Italy.

METHODS

Consecutive subjects seen at 34 Italian allergy centers from October to December 2010 were investigated both by specific interview and by skin prick test (SPT) with As extract.

RESULTS

A total of 10 570 subjects were screened, of which 474 (4.5%) scored positive on Anisakis SPT and 66 of these (14% of those sensitized; 0.6% of the studied population) had a history of As allergy. Marinated anchovies were the most frequent cause of allergic reactions. Thirty-four (52%) patients were mono-sensitized to Anisakis. Sensitization rate showed marked geographic differences (range: 0.4-12.7%), being highest along the Adriatic and Tyrrhenian coasts, where homemade marinated anchovies are an age-old tradition. In inland centers in northern Italy, the prevalence was directly related to the number of inhabitants. The analysis of the impact of immigration on the prevalence of Anisakis hypersensitivity showed that about 60% of sensitized subjects in Milano and Torino came from southern Italy or from non-European countries.

CONCLUSIONS

Anisakis hypersensitivity and allergy are mainly a matter of dietary habits. Areas where marinated anchovies are popular can be considered as 'endemic' for this type of food allergy, whereas immigration and, possibly, new or imported trendy food styles, such as eating raw fish carpaccios or sushi, are a major causative factor in big cities of inland zones.

Synergism between prior Anisakis simplex infections and intake of NSAIDs, on the risk of upper digestive bleeding: a case-control study

Background

The aim of this study was to investigate the relationship between prior Anisakis infections and upper gastrointestinal bleeding (UGIB), and its interaction with non-steroidal anti-inflammatory drug (NSAID) intake.

Methods/Principal Findings

We conducted a hospital-based case-control study covering 215 UGIB cases and 650 controls. Odds ratios (ORs) with their confidence intervals (95% CIs) were calculated, as well as the ratio of the combined effects to the sum of the separate effects of Anisakis allergic sensitization and NSAIDs intake. Prior Anisakis infections were revealed by the presence of anti-Anisakis IgE antibodies specific to the recombinant Ani s 1 and Ani s 7 allergens used as the targets in indirect ELISA. Prior Anisakis infections (OR 1.74 [95% CI: 1.10 to 2.75]) and the intake of NSAIDs (OR 6.63 [95% CI: 4.21 to 10.43]) increased the risk of bleeding. Simultaneous NSAIDs intake and Anisakis allergic sensitization increased the risk of UGIB 14-fold (OR = 14.46 [95% CI: 6.08 to 34.40]). This interaction was additive, with a synergistic index of 3.01 (95% CI: 1.18–7.71).

Conclusions

Prior Anisakis infection is an independent risk factor for UGIB, and the joint effect with NSAIDs is 3 times higher than the sum of their individual effects.

Anisakiasis is a worldwide re-emerging disease produced by the consumption of raw, lightly cooked, smoked or marinated fish containing live Anisakis larvae. In acute anisakiasis, mucosal lesions generated by the larvae may provoke upper gastrointestinal bleeding (UGIB). However, the effect of past unnoticed Anisakis infections as a risk factor for UGIB, and a possible synergism with other risk factors such as NSAIDs intake, have never been investigated. In this case-control study we observed that: i) prior Anisakis infections and NSAIDs intake are two independent risk factors for UGIB, and ii) that both risk factors act synergistically to the extent that their joint effect is 3 times higher than the sum of their individual effects. We concluded that, in countries where Anisakis infections are frequent, it would be wise to determine parasite-specific IgE antibodies and to conduct a closer follow-up of patients who consume raw or lightly cooked fish and who are prescribed NSAIDs for long periods.

Seroprevalence of antibodies against Anisakis simplex larvae among health-examined residents in three hospitals of southern parts of Korea

The present study was performed to estimate the seroprevalence of larval Anisakis simplex infection among the residents health-examined in 3 hospitals in southern parts of Korea. A total of 498 serum samples (1 serum per person) were collected in 3 hospitals in Busan Metropolitan city, Masan city, and Geoje city in Gyeongsangnam-do (Province) and were examined by IgE-ELISA and IgE-western blotting with larval A. simplex crude extract and excretory-secretory products (ESP). The prevalence of antibody positivity was 5.0% and 6.6% with ELISA against crude extracts and ESP, respectively. It was also revealed that infection occurred throughout all age groups and higher in females than in males. A specific protein band of 130 kDa was detected from 10 patients with western blot analysis against crude extract and ESP among those who showed positive results by ELISA. Our study showed for the first time the seroprevalence of anisakiasis in Korea. The allergen of 130 kDa can be a candidate for serologic diagnosis of anisakiasis.

MISS-Prot: web server for self/non-self discrimination of protein residue networks in parasites; theory and experiments in Fasciola peptides and Anisakis allergens

Infections caused by human parasites (HPs) affect the poorest 500 million people worldwide but chemotherapy has become expensive, toxic, and/or less effective due to drug resistance. On the other hand, many 3D structures in Protein Data Bank (PDB) remain without function annotation. We need theoretical models to quickly predict biologically relevant Parasite Self Proteins (PSP), which are expressed differentially in a given parasite and are dissimilar to proteins expressed in other parasites and have a high probability to become new vaccines (unique sequence) or drug targets (unique 3D structure). We present herein a model for PSPs in eight different HPs (Ascaris, Entamoeba, Fasciola, Giardia, Leishmania, Plasmodium, Trypanosoma, and Toxoplasma) with 90% accuracy for 15 341 training and validation cases. The model combines protein residue networks, Markov Chain Models (MCM) and Artificial Neural Networks (ANN). The input parameters are the spectral moments of the Markov transition matrix for electrostatic interactions associated with the protein residue complex network calculated with the MARCH-INSIDE software. We implemented this model in a new web-server called MISS-Prot (MARCH-INSIDE Scores for Self-Proteins). MISS-Prot was programmed using PHP/HTML/Python and MARCH-INSIDE routines and is freely available at: . This server is easy to use by non-experts in Bioinformatics who can carry out automatic online upload and prediction with 3D structures deposited at PDB (mode 1). We can also study outcomes of Peptide Mass Fingerprinting (PMFs) and MS/MS for query proteins with unknown 3D structures (mode 2). We illustrated the use of MISS-Prot in experimental and/or theoretical studies of peptides from Fasciola hepatica cathepsin proteases or present on 10 Anisakis simplex allergens (Ani s 1 to Ani s 10). In doing so, we combined electrophoresis (1DE), MALDI-TOF Mass Spectroscopy, and MASCOT to seek sequences, Molecular Mechanics + Molecular Dynamics (MM/MD) to generate 3D structures and MISS-Prot to predict PSP scores. MISS-Prot also allows the prediction of PSP proteins in 16 additional species including parasite hosts, fungi pathogens, disease transmission vectors, and biotechnologically relevant organisms.

The hidden sense of symptoms: urticaria can be beneficial

Evolutionary Medicine can be useful when analysing the origin of disease and symptoms. Acute urticaria or anaphylaxis is bothersome and potentially life-threatening. We analyse this symptom-complex in the context of Gastro-allergic Anisakiasis (GAA), where the human is an incidental host for the cosmopolitan fish-nematode Anisakis simplex (A. simplex). The immunological response against this nematode resembles that against other helminths, but overt expression of allergic symptoms is by far more frequent in GAA. This could be due to the missing co-evolutionary relationship between host and parasite. Features of acute gastric parasitism with and without overt allergic type 1 hypersensitivity symptoms are compared with the abdominal complications in intestinal Anisakiasis, where clinically visible IgE mediated symptoms are missing. In GAA, parasite induced chronic abdominal complications are missing. We postulate that urticaria in GAA can be considered the price for rapidly expelling the live larva of A. simplex in those subjects whose evolutionary history made them more resistant to other helminth parasites. Further, urticaria is explained as a possibly exaggerated immunopathological feature in this special type of acute parasitism, where sensitized mast-cells are not only present in the skin, but also in the gastro-intestinal mucosa. This evolutionary analysis of clinical observations is the first known report that addresses the possible beneficial feature of hypersensitivity type 1 response with overt allergic urticaria-anaphylaxis in GAA and confers an evolutionary based sense to the acute IgE-mediated reaction.