Influence of confluent marine currents in an ecotonal region of the South-West Atlantic on the distribution of larval anisakids (Nematoda: Anisakidae).

BACKGROUND: In the marine environment, transitional zones between major water masses harbour high biodiversity, mostly due to their productivity and by containing representatives of species characteristic of adjacent communities. With the aim of assessing the value of larval Anisakis as zoogeographical indicators in a transitional zone between subtropical and sub-Antarctic marine currents, larvae obtained from Zenopsis conchifer were genetically identified. Larvae from Pagrus pagrus and Merluccius hubbsi from two adjacent zoogeographical provinces were also sequenced. RESULTS: Four species were genetically identified in the whole sample, including Anisakis typica, A. pegreffii, A. berlandi and a probably new species related to A. paggiae. Anisakis typica and A. pegreffii were identified as indicators of tropical/subtropical and sub-Antarctic waters, respectively, and their presence evidenced the transitional conditions of the region. Multivariate analyses on prevalence and mean abundance of Anisakis spp. of 18 samples represented by 9 fish species caught south of 35°S determined that host trophic level and locality of capture were the main drivers of the distribution of parasites across zoogeographical units in the South-West Atlantic. CONCLUSIONS: Most samples followed a clear zoogeographical pattern, but the sample of Z. conchifer, composed mostly of A. typica, was an exception. This finding suggests that population parameters of A. typica and A. pegreffii could differ enough to be considered as a surrogates of the identity of larvae parasitizing a given host population and, therefore, a step forward the validation of the use of larval Anisakis as biological indicators for studies on host zoogeography.

Anisakidae and Raphidascarididae larvae parasitizing Selene setapinnis (Mitchill, 1815) in the State of Rio de Janeiro, Brazil.

Between February and August, 2012, thirty specimens of Atlantic moonfish, Selene setapinnis, were purchased in local markets in Niterói, State of Rio de Janeiro, Brazil, with the aim of analyzing the presence of anisakid nematodes, establishing their rates of parasitism and infection sites, due to importance in the sanitary inspection. A total of sixty nematode larvae, belonging to at least two species were found: nine larvae of Terranova sp., Anisakidae, with prevalence (P) of 13.3%, mean intensity (MI) of 2.25, mean abundance (MA) of 0.30 and range of infection intensity (RI) from 1 to 6; and 51 larvae of Hysterothylacium fortalezae, Raphidascarididae, with P = 26.7%, MI = 6.40, MA = 1.70, and RI = 1-17. The infection sites for Terranova sp. were the mesentery and liver serosa; and for H. fortalezae, the infection sites were the mesentery, abdominal cavity and liver serosa. New morphological data from scanning electron microscopy, on the external structures of H. fortalezae (mainly at the posterior end), are presented. This is the first report of H. fortalezae parasitizing S. setapinnis.

Anisakidae and Raphidascarididae larvae parasitizing Selene setapinnis (Mitchill, 1815) in the State of Rio de Janeiro, Brazil / Larvas Anisakidae e Raphidascarididae parasitos de Selene setapinnis (Mitchill, 1815) no Estado do Rio de Janeiro, Brasil

Between February and August, 2012, thirty specimens of Atlantic moonfish, Selene setapinnis, were purchased in local markets in Niterói, State of Rio de Janeiro, Brazil, with the aim of analyzing the presence of anisakid nematodes, establishing their rates of parasitism and infection sites, due to importance in the sanitary inspection. A total of sixty nematode larvae, belonging to at least two species were found: nine larvae of Terranova sp., Anisakidae, with prevalence (P) of 13.3%, mean intensity (MI) of 2.25, mean abundance (MA) of 0.30 and range of infection intensity (RI) from 1 to 6; and 51 larvae of Hysterothylaciumfortalezae, Raphidascarididae, with P = 26.7%, MI = 6.40, MA = 1.70, and RI = 1-17. The infection sites for Terranova sp. were the mesentery and liver serosa; and for H. fortalezae, the infection sites were the mesentery, abdominal cavity and liver serosa. New morphological data from scanning electron microscopy, on the external structures of H. fortalezae (mainly at the posterior end), are presented. This is the first report of H. fortalezae parasitizing S. setapinnis.(AU)

De Fevereiro a Agosto de 2012, trinta espécimes de peixe galo, Selene setapinnis, foram adquiridos de mercados locais em Niterói, Estado do Rio de Janeiro, Brasil, com o objetivo de analisá-los quanto à presença de nematoides anisaquídeos, estabelecendo seus índices parasitários e sítios de infecção, devido a sua importância na inspeção sanitária. Do total de sessenta larvas de nematoides, pelo menos duas espécies foram encontradas: nove larvas de Terranova sp., Anisakidae, com prevalência (P) de 13,3%, intensidade média (IM) de 2,25, abundância média (AM) de 0,30, e amplitude de variação da intensidade de infecção (AI) de 1 a 6; e 51 larvas de Hysterothylaciumfortalezae, Raphidascarididae, com P = 26,7%, IM = 6,40, AM = 1,70, e AI = 1 a 17. Os sítios de infecção para Terranova sp. foram o mesentério e a serosa do fígado; e para H. fortalezae, os sítios de infecção foram o mesentério, cavidade abdominal e serosa do fígado. Novos dados morfológicos das estruturas externas, principalmente da extremidade posterior de H. fortalezae, são evidenciados por microscopia eletrônica de varredura. Este é o primeiro relato de H. fortalezae parasitando S. setapinnis.(AU)

Anisakidae and Raphidascarididae larvae parasitizing Selene setapinnis (Mitchill, 1815) in the State of Rio de Janeiro, Brazil / Larvas Anisakidae e Raphidascarididae parasitos de Selene setapinnis (Mitchill, 1815) no Estado do Rio de Janeiro, Brasil

Between February and August, 2012, thirty specimens of Atlantic moonfish, Selene setapinnis, were purchased in local markets in Niterói, State of Rio de Janeiro, Brazil, with the aim of analyzing the presence of anisakid nematodes, establishing their rates of parasitism and infection sites, due to importance in the sanitary inspection. A total of sixty nematode larvae, belonging to at least two species were found: nine larvae of Terranova sp., Anisakidae, with prevalence (P) of 13.3%, mean intensity (MI) of 2.25, mean abundance (MA) of 0.30 and range of infection intensity (RI) from 1 to 6; and 51 larvae of Hysterothylacium fortalezae, Raphidascarididae, with P = 26.7%, MI = 6.40, MA = 1.70, and RI = 1-17. The infection sites for Terranova sp. were the mesentery and liver serosa; and for H. fortalezae, the infection sites were the mesentery, abdominal cavity and liver serosa. New morphological data from scanning electron microscopy, on the external structures of H. fortalezae (mainly at the posterior end), are presented. This is the first report of H. fortalezae parasitizing S. setapinnis.

De Fevereiro a Agosto de 2012, trinta espécimes de peixe galo, Selene setapinnis, foram adquiridos de mercados locais em Niterói, Estado do Rio de Janeiro, Brasil, com o objetivo de analisá-los quanto à presença de nematoides anisaquídeos, estabelecendo seus índices parasitários e sítios de infecção, devido a sua importância na inspeção sanitária. Do total de sessenta larvas de nematoides, pelo menos duas espécies foram encontradas: nove larvas de Terranova sp., Anisakidae, com prevalência (P) de 13,3%, intensidade média (IM) de 2,25, abundância média (AM) de 0,30, e amplitude de variação da intensidade de infecção (AI) de 1 a 6; e 51 larvas de Hysterothylacium fortalezae, Raphidascarididae, com P = 26,7%, IM = 6,40, AM = 1,70, e AI = 1 a 17. Os sítios de infecção para Terranova sp. foram o mesentério e a serosa do fígado; e para H. fortalezae, os sítios de infecção foram o mesentério, cavidade abdominal e serosa do fígado. Novos dados morfológicos das estruturas externas, principalmente da extremidade posterior de H. fortalezae, são evidenciados por microscopia eletrônica de varredura. Este é o primeiro relato de H. fortalezae parasitando S. setapinnis.

Experimental anisakid infections in mice.

Anisakidosis is a human parasitic disease caused by infections with members of the Anisakidae family. Accidental infection after fish intake affects the gastrointestinal tract as a consequence of mechanical damage caused by migrating larvae. Infections can also trigger allergies, hives, severe asthma or anaphylaxis with angioedema. Although mouse models of intraperitoneal antigenic stimulation exist, enabling immunological studies, few models using gastric introduction of live larvae are available for the study of immunological and gastrointestinal damage in mice. This study was designed to characterize serum reactivity against Anisakis spp. and Contracaecum spp. in Balb/c mice following orogastric inoculation and to assess gastrointestinal damage. These anisakid species were classified at the Universidade Federal Fluminense (UFF) School of Veterinary Medicine and materials for live larval inoculation were developed at the UFF Immunobiology laboratory. Live larvae were inoculated following injection with a NaCl solution. Blood samples were collected and sera screened for immunoglobulin (Ig)E and IgG anti-larva responses to both nematodes, specific for somatic and excretory/secretory antigens, by enzyme-linked immunosorbent assay (ELISA). The means of the optical densities were analysed using analysis of variance (ANOVA) with Tukey's post-hoc test and the general linear model. This analysis identified the presence of anti-IgG seroreactivity to both somatic and excretory/secretory Anisakis antigens in inoculated animals compared with controls (P< 0.001), and no gastric or intestinal damage was observed. These experiments demonstrated that introduction of live Contracaecum spp. into the gastrointestinal tract did not elicit serum sensitization in animals.

A technique for the intra-gastric administration of live larvae of Anisakis simplex in mice.

To understand the mechanisms of infection and to attempt to simulate human infection by the Anisakidae family, many in vivo experimental approaches have been developed. The aim was to develop and present a technique for the induction of an oral infection through the use of an intra-gastric gavage of live Anisakis simplex in mice. A commercial pediatric gastric tube (No. 4) was cut longitudinally to produce a 3-cm slit at the distal end where the larva was placed to then be administered to the stomach of the mouse. There were no abnormal clinical complications before, during or after the procedure. In conclusion oral infection through the direct delivery of larvae in the stomach is simple and effective.

Ocorrência de Contracaecum pelagicum Johnston & Mawson, 1942 (Nematoda, Anisakidae), em pinguim-de-magalhães (Spheniscus magellanicus Forster, 1781) (Aves, Spheniscidae) no litoral do Espírito Santo / Occurrence of Contracaecum pelagicum Johnston & Mawson, 1942 (Nematoda, Anisakidae) in Magellanic penguin (Spheniscus magellanicus Forster, 1781) (Aves, Spheniscidae) at Espírito Santo coast

The occurrence of gastrointestinal nematodes affecting a Magellanic penguin, which was submitted to necropsy after being found dead at the coast of Vitória, Espírito Santo State, Brazil, was reported. A great number of juveniles nematodes and 48 adults (24 males and 24 females) were found in the stomach of the penguin. The parasite was diagnosed as Contracaecum pelagicum in agreement with the number and the distribution of the precloacal and postcloacal papillae of the male specimens. Other characteristics as distribution of the labial papillae, intestinal caecum and ventricular appendix ratio, spicules length, and total body length ratio were also in accordance to the well-known variation for the species, confirming the diagnosis. This work is the first report of the parasitism by C. pelagicum in Magellanic penguin found in the Southeast of Brazil.(AU)

[Anisakidosis a marine parasitic zoonosis: unknown or emerging in Peru?]. / Anisakidosis: una zoonosis parasitaria marina desconocida o emergente en el Perú?

The purpose of this review is to show the experimental studies carried out on the biological cycle, culture, pathogenicity of the anisakidae nematode larvae and to disseminate the information regarding current epidemy and the probable emergence of anisakidosis in Peru, and in addition, to propose measures of prevention and control, as well as the perspective and need for investigation. The studies of experimental pathogenicity in cats, dos, and hamsters are incomplete. Eight cases of acute human anisakidosis have been reported (5 confirmed and 3 unconfirmed). It is probable that it emerges during the "El Niño" Weather Phenomenon; however, during normal conditions it is probably due to the increase of raw fish consumption and other factors. In the coast of Peru, five and four fishes of direct human consumption are parasited by the Anisakis simplex and Anisakis physeteris larva, respectively, and two fishes are parasited by the Pseudoterranova decipiens. The main host for the Anisakis simplex is the dolphin (Delphinus delphia), but the Contracaecum osculatum is hosted by the sea lion: Otaria byronia and Arctocephalus australis, P. decipiens parasita a O. byronia. Eviscerating the fish would be most adequate prevention method to lessen the risk of human infection. There is evidence that anisakidosis is an underestimated zoonosis in Peru, and that it is probably and emerging disease. Therefore, its presence is to be suspected in patients with the prototype clinical syndrome.

[Ecological aspects between Contracaecum sp. (Nematoda, Anisakidae) and the host Serrasalmus spilopleura Kner, 1860 (Pisces, Characidae) in natural populations of northeastern Argentina]. / Aspectos ecológicos de la relación parasitaria entre larvas de Contracaecum sp. (Nematoda, Anisakidae) y Serrasalmus spilopleura Kner, 1860 (Pisces, Characidae) en poblaciones naturales del nordeste argentino.

From February 1987 to February 1989, the populational biology of Contraceacum sp. (larvae) in its paratenic host, the fish Serrasalmus spilopleura Kner, 1860, was studied in two ponds in a subtropical permanent habitat northeastern of Argentina. Fishes from Ramada Paso pond presented 80% of prevalence and 1 to 132 larvae per fish while fishes from Aeroclub pond presented 63% of prevalence and 1 to 184 larvae per fish. Fishes collected from Aeroclub pond have shown a high prevalence of infection during the first period of study (1987), diminishing the following year. In fishes from Ramada Paso pond the prevalence varied not significatively during the two years. Prevalence and mean intensity of infection increase with body length and weight of the hosts. Sex of hosts is not an influential factor in parasitic level. The lenitic "closed" environmental (Ramada Paso pond) evidenced the greatest larvae mean intensity and prevalence. Although, the lenitic "open" environmental (Aeroclub pond) showed the greatest parasitic number of individuals in an infrapopulation. The spatial dispersion in both ponds were aggregated and fit well a negative binomial model. Nevertheless, the Aeroclub pond presented the greatest overdispersion.

Human case of gastric infection by a fourth larval stage of Pseudoterranova decipiens (Nematoda, Anisakidae).

Only three cases of human infection by anisakid nematodes have been reported in Chile since 1976. In the present case, an anisakid worm, identified as a fourth-stage Pseudoterranova decipiens larva, was removed with a gastroendoscopic biopsy clipper from the stomach of a 45 year-old man from southern Chile. The patient, who presented acute epigastric pain and a continuous sensation of having an empty stomach, reported having eaten smoked fish. The worm was fixed in 70% ethanol and cleaned in lactophenol for morphological study. The morphometric characteristics of the worm are described and drawn. Anisakid larvae in fish flesh can be killed by freezing or cooking.

Hysterothylacium pseudotumbili n.sp. (Nematoda: Anisakidae) from the marine fishes of Visakhapatnam, Bay of Bengal

Hysterothylacium pseudotumbili n.sp. del estómago y cavidad visceral de peces marinos, Chorineus tol Cuvier, Saurida undosquamis (Richardson), Lutianus russelli (Bleecker), Rastrilliger, kanagurta (Cuvier) y Saurida pseudotumbili Dutt y Vidyasagar colectados en Visakhapatnam (Bahía de Bengala) es descrito y representado en detalle. Un examen minucioso nos ha permitido establecer una nueva especie de Hysterothylacium para ubicar a dicho gusano. Muestra notables diferencias con otras especies conocidas de Hysterothylacium en relación a medidas del cuerpo, distribución de las papilas labiales, ubicación del anillo nervioso y poro excretorio, largo ciego intestinal, posición de la vulva, número y distribución de las papilas caudales y tamaño de las espículas. La nueva especie es designada como Hysterothylacium pseudotumbili. Saurida pseudotumbili es el nuevi huésped que se registra. Este es el primer reporte del género de este huésped. La costa de Visakhapatnam es la nueva localidad registrada