New insights into the diagnosis of cysticercoses in cattle and sheep at population and herd level

Ruminants are intermediate hosts of several cestodes including Taenia saginata in cattle and T. ovis in sheep. Larval stages of these cestodes manifest as cystic lesions in skeletal and heart muscle. Cysticercosis causes economic losses due to demotion or condemnation of infected carcasses. Because of the known low diagnostic sensitivity of the standard EU meat inspection protocol for the detection of T. saginata cysticerci, we performed an abattoir trial aiming to increase the detection rate. With the EU-approved meat inspection, bovine cysticercosis was diagnosed in 1.8% (20/1088) of the slaughtered animals. Additional incisions into the heart muscle revealed a further 29 cases, indicating a prevalence of at least 4.5%. Recently developed diagnostic strategies were applied as tools for risk management for an extended cysticercosis storm in a large sheep flock in Southwest England. At abattoir, 7% of the slaughtered lambs had been rejected due to T. ovis infection which was confirmed morphologically and genetically. To track the source of infection, 50 dog faecal samples collected from trails were analysed by Taeniid-egg isolation and further molecular specification. Further faecal samples from dogs, foxes and badgers from all farm fields were also investigated. Eventually, an egg-contaminated pasture could be identified which is frequently visited by dog walkers and which is the only common field where all the lambs have been grazed. = Wiederkäuer sind Zwischenwirte für verschiedene Bandwürmer einschliesslich Taenia saginata beim Rind und T. ovis beim Schaf. Larvale Stadien manifestieren sich als Zysten in der Skelett- und Herzmuskulatur. Die Cysticercose verursacht wirtschaftliche Verluste durch Herabstufung und Beschlagnahmung von infizierten Schlachttierkörpern. Wegen der bekannt geringen Sensitivität der standardmässigen EU-Fleischinspektionsmethode für den T. saginata Zystennachweis wurde ein Schlachthofversuch mit dem Ziel einer verbesserten Befundrate durchgeführt. Mit der EU-anerkannten Fleischinspektion wurde in 1.8% (20/1088) der Schlachttiere bovine Cysticercose diagnostiziert. Mit vermehrten Herzschnitten konnten 29 zusätzliche Fälle entdeckt werden, was einer Prävalenz von mindestens 4.5% entspricht. Neuste diagnostische Methoden dienten als Werkzeug für ein Risikomanagement eines ausgedehnten Cysticercose-Sturms in einer grossen Schafherde in Südwest-England. Am Schlachthof waren 7% der Schlachtlämmer wegen T. ovis Infektionen abgewiesen worden, welche morphologisch und genetisch bestätigt wurden. Um die Infektionsquelle zu finden, wurden aus 50 Hunde-Kotproben von Spazierwegen Taeniiden-Eier isoliert und genetisch identifiziert. Weitere Kotproben von Hunden, Füchsen und Dachsen von allen Feldern wurden untersucht. Die kontaminierte Fläche konnte auf ein Feld eingegrenzt werden, welches von Hundehaltern stark frequentiert und als einziges von allen Lämmern beweidet wurde

Estimating prevalence and diagnostic test characteristics of bovine cysticercosis in Belgium in the absence of a ‘gold standard’ reference test using a Bayesian approach

A Bayesian model was developed to estimate values for the prevalence and diagnostic test characteristics of bovine cysticercosis (Taenia saginata) by combining results of four imperfect tests. Samples of 612 bovine carcases that were found negative for cysticercosis during routine meat inspection collected at three Belgian slaughterhouses, underwent enhanced meat inspection (additional incisions in the heart), dissection of the predilection sites, B158/B60 Ag-ELISA and ES Ab-ELISA. This Bayesian approach allows for the combination of prior expert opinion with experimental data to estimate the true prevalence of bovine cysticercosis in the absence of a gold standard test. A first model (based on a multinomial distribution and including all possible interactions between the individual tests) required estimation of 31 parameters, while only allowing for 15 parameters to be estimated. Including prior expert information about specificity and sensitivity resulted in an optimal model with a reduction of the number of parameters to be estimated to 8. The estimated bovine cysticercosis prevalence was 33.9% (95% credibility interval: 27.7-44.4%), while apparent prevalence based on meat inspection is only 0.23%. The test performances were estimated as follows (sensitivity (Se) specificity (Sp)): enhanced meat inspection (Se 2.87% - Sp 100%), dissection of predilection sites (Se 69.8% - Sp 100%), Ag-ELISA (Se 26.9% - Sp 99.4%), Ab-ELISA (Se 13.8% - Sp 92.9%)

Monoclonal antibody-based localization of major diagnostic antigens in metacestode tissue, excretory/secretory products, and extracellular vesicles of Echinococcus species

Alveolar (AE) and cystic echinococcosis (CE) are severe parasitic zoonoses caused by the larval stages of Echinococcus multilocularis and E. granulosus sensu lato, respectively. A panel of 7 monoclonal antibodies (mAbs) was selected against major diagnostic epitopes of both species. The binding capacity of the mAbs to Echinococcus spp. excretory/secretory products (ESP) was analyzed by sandwich-ELISA, where mAb Em2G11 and mAb EmG3 detected in vitro extravesicular ESP of both E. multilocularis and E. granulosus s.s. These findings were subsequently confirmed by the detection of circulating ESP in a subset of serum samples from infected hosts including humans. Extracellular vesicles (EVs) were purified, and the binding to mAbs was analyzed by sandwich-ELISA. Transmission electron microscopy (TEM) was used to confirm the binding of mAb EmG3 to EVs from intravesicular fluid of Echinococcus spp. vesicles. The specificity of the mAbs in ELISA corresponded to the immunohistochemical staining (IHC-S) patterns performed on human AE and CE liver sections. Antigenic small particles designated as ‘‘spems’’ for E. multilocularis and ‘‘spegs’’ for E. granulosus s.l. were stained by the mAb EmG3IgM, mAb EmG3IgG1, mAb AgB, and mAb 2B2, while mAb Em2G11 reacted with spems and mAb Eg2 with spegs only. The laminated layer (LL) of both species was strongly visualized by using mAb EmG3IgM, mAb EmG3IgG1, mAb AgB, and mAb 2B2. The LL was specifically stained by mAb Em2G11 in E. multilocularis and by mAb Eg2 in E. granulosus s.l. In the germinal layer (GL), including the protoscoleces, a wide staining pattern with all structures of both species was observed with mAb EmG3IgG1, mAb EmG3IgM, mAb AgB, mAb 2B2, and mAb Em18. In the GL and protoscoleces, the mAb Eg2 displayed a strong E. granulosus s.l. specific binding, while mAb Em2G11 exhibited a weak granular E. multilocularis specific reaction. The most notable staining pattern in IHC-S was found with mAb Em18, which solely bound to the GL and protoscoleces of Echinococcus species and potentially to primary cells. To conclude, mAbs represent valuable tools for the visualization of major antigens in the most important Echinococcus species, as well as providing insights into parasite-host interactions and pathogenesis

Special considerations for studies of extracellular vesicles from parasitic helminths: A community‐led roadmap to increase rigour and reproducibility

Over the last decade, research interest in defining how extracellular vesicles (EVs) shape cross-species communication has grown rapidly. Parasitic helminths, worm species found in the phyla Nematoda and Platyhelminthes, are well-recognised manipulators of host immune function and physiology. Emerging evidence supports a role for helminth-derived EVs in these processes and highlights EVs as an important participant in cross-phylum communication. While the mammalian EV field is guided by a community-agreed framework for studying EVs derived from model organisms or cell systems [e.g., Minimal Information for Studies of Extracellular Vesicles (MISEV)], the helminth community requires a supplementary set of principles due to the additional challenges that accompany working with such divergent organisms. These challenges include, but are not limited to, generating sufficient quantities of EVs for descriptive or functional studies, defining pan-helminth EV markers, genetically modifying these organisms, and identifying rigorous methodologies for in vitro and in vivo studies. Here, we outline best practices for those investigating the biology of helminth-derived EVs to complement the MISEV guidelines. We summarise community-agreed standards for studying EVs derived from this broad set of non-model organisms, raise awareness of issues associated with helminth EVs and provide future perspectives for how progress in the field will be achieved

Ticks on dogs and cats: a pet owner-based survey in a rural town in northeastern Switzerland

Changes in the endemic foci of tick populations and invasions of tick species to new areas have become evident in Europe, leading to changes in the epidemiology of tick-transmitted diseases. However, data about tick infestations of pet animals are limited. Following the recent identification of a new focus of canine babesiosis in northeastern Switzerland, we investigated the occurrence of tick vectors in this region by using a pet owner-based sampling strategy. All dog owners in a rural town were sent postal requests to send ticks from their dogs and cats over two consecutive years, beginning in April 2012. In total 3003 ticks were submitted for identification from 249 dogs (approximately 20% of the resident dog population) and from 117 cats. Ixodes ricinus was the most abundant species identified in 96.8% (n=2124) and 74.3% (n=601) of the individual samples submitted from dogs and cats, respectively. Two other tick species, I. hexagonus and Dermacentor reticulatus, were recorded on both host species, with host infestation prevalences below 2%. On cats (but not on dogs), as many as 24.0% (n=194) of the specimens were identified as a fourth tick species, I. trianguliceps. Overall, 93.5% of the ticks were adults (93.8% and 93.0% in dogs and cats), 4.4% nymphs (5.7% in dogs and 1% in cats) and 2% larvae (0.5% and 6.0% in dogs and cats), respectively. The highest infestation intensity was 49 I. ricinus ticks from an individual dog. However, 55.6% of the submissions from dogs and 24.8% from cats contained only one tick. This survey demonstrated that pet owners can contribute to a cost-effective tick surveillance and identified a new tick focus of D. reticulatus. The finding of I. trianguliceps exclusively on cats might be related to behavioural traits of the cats or to a more readily detection of these very small ticks during petting by their owners

Prognostic markers in acute babesia canis infections

BACKGROUND Canine babesiosis, caused by Babesia canis, is a prevalent and clinically relevant disease in Europe. Severe acute babesiosis is characterized by a high mortality but prognosis is not always correlated with clinical signs nor with the level of parasitemia. OBJECTIVE This study evaluated prognostic markers associated with poor outcomes in acute Babesia canis infections. ANIMALS AND METHODS We compared the results of routine laboratory profiles, hand-held lactate and glucose analyzer, and the acute phase response in 2 groups of naturally infected dogs (7 survivors and 8 nonsurvivors). Samples were collected at the time of first admission and before any treatment. Subsequently, the course of prognostic markers was followed in 3 dogs experimentally inoculated with B. canis. RESULTS Nonsurvivors showed significantly higher concentrations of lactate, triglycerides and phosphate and lower hematocrit, leukocyte counts, total serum protein concentrations, and thrombocyte counts when compared to survivors. All nonsurvivors (8/8) had hyperlactatemia, whereas most survivors (6/7) had values within the reference range. All survivors had leucocyte counts within the reference range, unlike the nonsurvivors, which showed leukopenia. During the course of acute babesiosis, the variables serum lactate, triglyceride, and phosphate concentrations, and thrombocyte count only exceeded a prognostic threshold during acute crisis. CONCLUSIONS AND CLINICAL IMPORTANCE Poor outcome in acute B. canis infection is indicated by changes in the laboratory profile. Intensive care should be considered for dogs presenting with moderate anemia, severe thrombocytopenia, mild to moderate leukopenia, hyperlactatemia, moderately increased serum phosphate, and triglyceride concentrations, and moderately decreased total serum protein concentrations

Successful intestinal Echinococcus multilocularis oncosphere invasion and subsequent hepatic metacestode establishment in resistant RccHan™:WIST rats after pharmacological immunosuppression

Susceptibility/resistance to larval Echinococcus multilocularis infection varies greatly depending on host species and strains. Whereas several mice strains and non-human primates are highly susceptible to alveolar echinococcosis, rats and most of humans are considered as more resistant. In this study, we aimed to elucidate factors responsible for host resistance in rats (Experiments A-D). (A) The parasite establishment was not observed in immunocompetent Wistar rats orally inoculated with sodium hypochlorite resistant eggs with/without pig bile, or activated/non-activated oncospheres (NAO). Peritoneal inoculation with NAO or metacestode tissue allowed the parasite establishment in rats. (B) T-cell-deficient athymic nude rats showed complete resistance against the metacestode establishment after oral inoculation with parasite eggs. This finding suggests that T-cell-independent parasite clearance occurred in the animals during early phase of the parasite invasion. Finally, Wistar rats that received pharmacological immunosuppression using either dexamethasone (DMS) alone or methotrexate (MTX) i.p. alone or a combination of these compounds were orally inoculated with the parasite's eggs. As a result (D), successful establishment of metacestode with protoscoleces was observed in all 3 rats treated with DMS (s.c.) alone or in all 6 rats treated with DMS (s.c.) plus MTX but not in 8 rats with MTX alone, suggesting that factors affected by DMS treatment are responsible to regulate the parasite invasion and establishment

libPRISM: an intelligent adaptation of prefetch and SMT levels

Current microprocessors include several knobs to modify the hardware behavior in order to improve performance under different workload demands. An impractical and time consuming offline profiling is needed to evaluate the design space to find the optimal knob configuration. Different knobs are typically configured in a decoupled manner to avoid the time-consuming offline profiling process. This can often lead to underperforming configurations and sometimes to conflicting decisions that jeopardize system power- performance efficiency. Thus, a dynamic management of the different hardware knobs is necessary to find the knob configuration that maximizes system power-performance efficiency without the burden of offline profiling. In this paper, we propose libPRISM, an infrastructure that enables the transparent management of multiple hardware knobs in order to adapt the system to the evolving demands of hardware resources in different workloads. We use libPRISM to implement a policy that maximizes system performance without degrading energy efficiency by dynamically managing the SMT level and prefetcher hardware knobs of an IBM POWER8 system. We evaluate our solution using 24 applications from 3 different parallel benchmarks suites without the need of offline profiling or workload modification. Overall, the solution increases performance up to 220% (15.4% on average) and reduces dynamic power consumption up to 13% (2.0% on average) when compared to the static default knob configuration.This work has been supported by the RoMoL ERC Advanced Grant (GA 321253), by the European HiPEAC Network of Excellence, by the Spanish Ministry of Science and Innovation (contracts TIN2015-65316-P), by Generalitat de Catalunya (contracts 2014-SGR-1051 and 2014-SGR-1272) and by IBM/BSC Deep Learning Center initiative. This research was developed in part with funding from the Defense Advanced Research Projects Agency (DARPA). The views, opinions and/or findings expressed are those of the author and should not be interpreted as representing the official views or policies of the Department of Defense or the U.S. Government. M. Moreto has been partially supported by the Ministry of Economy and Competitiveness under Juan de la Cierva postdoctoral fellowship number JCI-2012-15047. M. Casas is supported by the Secretary for Universities and Research of the Ministry of Economy and Knowledge of the Government of Catalonia and the Cofund programme of the Marie Curie Actions of the 7th R&D Framework Programme of the European Union (Contract 2013 BP B 00243).Peer Reviewe

libPRISM: an intelligent adaptation of prefetch and SMT levels

Current microprocessors include several knobs to modify the hardware behavior in order to improve performance under different workload demands. An impractical and time consuming offline profiling is needed to evaluate the design space to find the optimal knob configuration. Different knobs are typically configured in a decoupled manner to avoid the time-consuming offline profiling process. This can often lead to underperforming configurations and sometimes to conflicting decisions that jeopardize system power- performance efficiency. Thus, a dynamic management of the different hardware knobs is necessary to find the knob configuration that maximizes system power-performance efficiency without the burden of offline profiling. In this paper, we propose libPRISM, an infrastructure that enables the transparent management of multiple hardware knobs in order to adapt the system to the evolving demands of hardware resources in different workloads. We use libPRISM to implement a policy that maximizes system performance without degrading energy efficiency by dynamically managing the SMT level and prefetcher hardware knobs of an IBM POWER8 system. We evaluate our solution using 24 applications from 3 different parallel benchmarks suites without the need of offline profiling or workload modification. Overall, the solution increases performance up to 220% (15.4% on average) and reduces dynamic power consumption up to 13% (2.0% on average) when compared to the static default knob configuration.This work has been supported by the RoMoL ERC Advanced Grant (GA 321253), by the European HiPEAC Network of Excellence, by the Spanish Ministry of Science and Innovation (contracts TIN2015-65316-P), by Generalitat de Catalunya (contracts 2014-SGR-1051 and 2014-SGR-1272) and by IBM/BSC Deep Learning Center initiative. This research was developed in part with funding from the Defense Advanced Research Projects Agency (DARPA). The views, opinions and/or findings expressed are those of the author and should not be interpreted as representing the official views or policies of the Department of Defense or the U.S. Government. M. Moreto has been partially supported by the Ministry of Economy and Competitiveness under Juan de la Cierva postdoctoral fellowship number JCI-2012-15047. M. Casas is supported by the Secretary for Universities and Research of the Ministry of Economy and Knowledge of the Government of Catalonia and the Cofund programme of the Marie Curie Actions of the 7th R&D Framework Programme of the European Union (Contract 2013 BP B 00243).Peer Reviewe