Compilation of 29 years of postmortem examinations identifies major shifts in equine parasite prevalence from 2000 onwards.

Horses are infected by a wide range of parasite species that form complex communities. Parasite control imposes significant constraints on parasite communities whose monitoring remains, however, difficult to track through time. Postmortem examination is a reliable method to quantify parasite communities. Here, we compiled 1,673 necropsy reports accumulated over 29 years, in the reference necropsy centre from Normandy (France). The burden of non-strongylid species was quantified and the presence of strongylid species was noted. Details of horse deworming history and the cause of death were registered. Building on these data, we investigated the temporal trend in non-strongylid epidemiology and we determined the contribution of parasites to the deaths of horses throughout the study period. Data analyses revealed the seasonal variations of non-strongylid parasite abundance and reduced worm burden in race horses. Beyond these observations, we found a shift in the species responsible for fatal parasitic infection from the year 2000 onward, whereby fatal cyathostominosis and Parascaris spp. infection have replaced cases of death caused by Strongylus vulgaris and tapeworms. A concomitant break in the temporal trend of parasite species prevalence was also found within a 10 year window (1998-2007) that has seen the rise of Parascaris spp. and the decline of both Gasterophilus spp. and tapeworms. A few cases of parasite persistence following deworming were identified, which all occurred after 2000. Altogether, these findings provide insights into major shifts in non-strongylid parasite prevalence and abundance over the last 29 years. They also underscore the critical importance of Parascaris spp. in young equids.

Local immune depression in Baltic cod (Gadus morhua) liver infected with Contracaecum osculatum.

Third-stage larvae of the anisakid nematode Contracaecum osculatum infecting cod (Gadus morhua) liver elicit a host immune response involving both innate and adaptive factors, but the reactions differ between liver and spleen. Inflammatory reactions occur in both liver and spleen, but a series of immune effector genes are downregulated in liver infected with nematodes whereas these genes in spleen from the same fish are upregulated. A series of novel primer and probe sets targeting cod immune responses were developed and applied in a real-time quantitative polymerase chain reaction set-up to measure the expression of immune-relevant genes in liver and spleen of infected and uninfected cod. In infected liver, 12 of 23 genes were regulated. Genes encoding cytokines associated with inflammatory reactions (IL-1ß, IL-6, IL-8) were significantly upregulated, whereas genes encoding effector molecules, assisting the elimination of pathogens, C-reactive protein (CRP)-PII, hepcidin, lysozyme G1, lysozyme G2, C3 and IgDm, were significantly downregulated. The number of downregulated genes increased with the parasite burden. In spleen, 14 of 23 immune genes showed significant regulation and nine of these were upregulated, including genes encoding CRPI, CRPII, C3, hepcidin and transferrin. The general gene expression level was higher in spleen compared to liver, and although inflammation was induced in nematode-infected liver, the effector molecule genes were depressed, which suggests a worm-induced immune suppression locally in the liver.

Primeiro relato de Hysterothylacium deardorffoverstreetorum (Raphidascarididae) em bijupirá de criação, Rachycentron canadum (Linnaeus 1766), no Brasil / First report of Hysterothylacium deardorffoverstreetorum (Raphidascarididae) in cobia (Rachycentron canadum (Linnaeus 1766) farming in Brazil

O objetivo do presente estudo foi registrar a ocorrência de larva de nematoide da família Raphidascarididae, Hysterothylacium deardorffoverstreetorum, em bijupirá Rachycentron canadum (Linnaeus, 1766), criado e alimentado com ração e "trashfish" em fazendas marinhas localizadas no Rio de Janeiro, Brasil, alertando para possíveis riscos zoonóticos ao se usar esse tipo de alimentação para criação de peixes. Foram necropsiados 15 animais. Os parasitas encontrados foram coletados, fixados e, posteriormente, conservados em álcool a 70°GL, clarificados e identificados. Em todos os animais necropsiados, apenas um espécime estava parasitado com uma larva de Hysterothylacium deardorffoverstreetorum na serosa do fígado do peixe e conclui-se que a presença desse parasita em bijupirá de criação alimentado por "trashfish pode estar associada à alimentação, indicando, assim, um potencial risco zoonótico.(AU)

The aim of this study was to record the occurrence of nematode larvae of the Raphidascarididae family, Hysterothylacium deardorffoverstreetorum in cobia Rachycentron canadum (Linnaeus, 1766) grown and fed with trashfish in marine farms located in Rio de Janeiro, Brazil, warning regarding possible zoonotic risk using this type of food for fish. Fifteen animals were necropsied. Parasites found were collected, fixed and later preserved in alcohol 70°GL, clarified and identified. In all animals necropsied, only one specimen was infested with a Hysterothylacium deardorffoverstreetorum larvae in the serosa of fish liver. It is concluded that the presence of the parasite in cobia culture fed with trashfish may be associated with a potential zoonotic risk.(AU)

Good outcome with early empiric treatment of neural larva migrans due to Baylisascaris procyonis.

We report a remarkably good outcome in a 14-month-old boy with early clinical diagnosis and aggressive empirical treatment of neural larva migrans caused by the raccoon roundworm Baylisascaris procyonis. He presented with fever, meningismus, lethargy, irritability and asymmetric spastic extremity weakness. Early findings of marked blood and cerebrospinal fluid eosinophilia and of diffuse white matter signal abnormality in the brain and spinal cord on MRI suggested a parasitic encephalomyelitis. Rapid presumptive treatment with albendazole and high-dose steroids halted progression of clinical signs. The diagnosis was confirmed by 2 sequential enzyme-linked immunosorbent assay studies positive for B procyonis serum immunoglobulin G and by Western blot. Field examination with soil sampling yielded infective Baylisascaris eggs. Repeat MRI 3 months later showed atrophy and diffuse, chronic white matter abnormalities, discordant with the marked clinical improvement in this interval. At 10 months, residual neurologic deficits included subtle paraparesis and moderate language delay. This case is the first in which spinal involvement in human Baylisascaris infection was clinically suspected and confirmed by neuroimaging. Importantly, early diagnosis and aggressive treatment of Baylisascaris meningo-encephalitis and myelitis with albendazole and high-dose steroids likely contributed to the good outcome in this patient, in contrast with previous reports.

The trouble with sealworms (Pseudoterranova decipiens species complex, Nematoda): a review.

Sealworms or codworms, larvae of ascaridoid nematodes belonging to the Pseudoterranova decipiens species complex, infect the flesh of numerous species of marine and euryhaline fish, and have proven a chronic and costly cosmetic problem for seafood processors. Moreover, the parasite may cause abdominal discomfort in humans when consumed in raw, undercooked or lightly marinated fish. In this review, the phylogeny, life cycle and distributions of sealworms are discussed along with biotic and abiotic factors which may influence distributions of these parasites in their intermediate and final hosts. Also considered here are efforts to control the problem through commercial fishing practices, fish processing technology, and the reduction of infection parameters in marine fish populations by biological means. Ironically, concern over sealworm problem has subsided in some fisheries in recent years, not as a result of falling infection parameters in fish stocks or innovations in processing technology, but as a consequence of declines in abundance and size of groundfish.