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Helminth parasites of the wood mouse, Apodemus sylvaticus (n = 440), were surveyed in five localities, comprising woodland and grassland sites, in Southern England. Seven species of helminths were identified, among which Heligmosomoides polygyrus and Syphacia stroma were dominant (prevalence = 79.1% and 54.1%, respectively). Less common species were the trematode Corrigia vitta (14.8%), cestodes Catenotaenia pusilla (8.4%), Hydatigera taeniaeformis (4.1%) and Microsomacanthus crenata (3.4%) and the nematode Aonchotheca murissylvatici (0.2%). Differences in prevalences between localities were found for H. polygyrus, H. taeniaeformis and M. crenata and in abundances of H. polygyrus, S. stroma and C. vitta. Age-dependent increases in both parameters were identified among species and for helminth species richness. The only species to show significant host sex bias was S. stroma with prevalence values being higher in male mice. A number of different methods for exploiting raw data, and data corrected for significant confounding factors, were used to determine whether there were significant associations (prevalence) between species or quantitative interactions (abundance). The strongest evidence for a positive association was shown in concurrent infections with the trematode C. vitta and the cestode C. pusilla (significant in the whole dataset and evident in each locality, both sexes and both age classes). The abundance of C. pusilla was also higher in mice with C. vitta and vice versa. Overall, however, there was little support for associations or quantitative interactions between species, especially after data had been corrected for significant extrinsic/intrinsic factors, and we conclude that the helminths of wood mice in these communities are largely non-interactive and hence, perhaps better referred to as assemblages.
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Cestodos , Helmintiasis Animal , Helmintos , Nematospiroides dubius , Parásitos , Femenino , Ratones , Animales , Masculino , Helmintiasis Animal/epidemiología , Helmintiasis Animal/parasitología , Murinae/parasitología , Inglaterra/epidemiologíaRESUMEN
The Journal of Helminthology (JHL) was first published in 1923 and was originally created as a house journal of the London School of Hygiene and Tropical Medicine. The JHL was devised by its first Editor, Robert Leiper, to allow for rapid publication of results from the Department of Helminthology and its offshoot the Institute of Agricultural Parasitology. From this initial narrow focus the JHL has subsequently become not only internationally recognized but also retained its original emphasis on morphological, taxonomic and life cycle studies while embracing the emergence of new fields and technological advancements. The present review covers the historical development of the JHL over the last century from 1923 to 2023.
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Parasitología , Publicaciones Periódicas como Asunto , Medicina Tropical , Animales , Parasitología/historia , Instituciones Académicas , Medicina Tropical/historia , EdiciónRESUMEN
The distributions of the nematode parasites Heligmosomoides polygyrus and Syphacia stroma were quantified in three equal-length sections along the intestine of wood mice (Apodemus sylvaticus) trapped in three different locations in the south of England. The distribution of H. polygyrus did not change in the presence of S. stroma, this species being largely confined to the anterior third of the intestine, whether S. stroma was or was not present. However, while in single infections with S. stroma, worms were equally distributed in the anterior and middle sections of the intestine, in the presence of H. polygyrus, a higher percentage of worms was located in the middle section. This was a dose-dependent response by S. stroma to increasing worm burdens with H. polygyrus, and even relatively low intensities of infection with H. polygyrus (e.g. ≤10 worms) were sufficient to cause a posterior redistribution of S. stroma into the middle section. A similar posterior shift in the percentage distribution of S. stroma in the intestine was evident in juvenile and mature mice of both sexes, and in mice from all three study sites. The ecological significance of these results is discussed.
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Pradera , Nematodos , Animales , Inglaterra , Femenino , Bosques , Intestinos , Masculino , Ratones , MurinaeRESUMEN
Reinhard Hoeepli was a Swiss-German physician with a distinguished career as a researcher and historian of medical parasitology. He spent the majority of his career at the Peking Union Medical College in Beijing, China, where he undertook research on host responses to parasitic infections, in particular describing the 'Splendore-Hoeppli phenomenon', between 1929 and 1952. During the Second World War, he acted as the Swiss honorary Consul in Japanese-occupied Beijing. After leaving China following the militarization of the College in the wake of the Korean War, he subsequently worked in Singapore and Liberia before retiring to Switzerland. Hoeppli is most widely known for his association with Sir Edmund Backhouse, a controversial and enigmatic Chinese scholar, who was his war-time patient towards the end of his life. With Hoeppli's encouragement, Backhouse wrote two scandalous and unpublishable memoirs which remained in Hoeppli's safe-keeping until his own death in 1973. However, the revelations by the historian Hugh Trevor-Roper in 1976 that Backhouse was a fraudster and fantasist has had a detrimental effect on Hoeppli's posthumous reputation that has overshadowed his many lifetime achievements. Alongside a biography of his life, an examination of the controversies of the Backhouse revelations on Hoeppli's repute is presented.
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Biografías como Asunto , Parasitología/historia , China , Historia del Siglo XX , Suiza , Segunda Guerra MundialRESUMEN
We study the change in magnetisation with paramagnetic Al addition in the CoFeNi0.5Cr0.5-Alx (x: 0, 0.5, 1, and 1.5) complex concentrated alloy. The compositions were developed utilising the Mulliken electronegativity and d-electron/atom ratio. Spherical FeCr rich nanoprecipitates are observed for X: 1.0 and 1.5 in an AlCoNi-rich matrix. A ~ 5 × increase in magnetisation (from 22 to 96 Am2/kg) coincides with this nanoprecipitate formation-the main magnetic contribution is determined to be from FeCr nanoprecipitates. The magnetisation increase is strange as paramagnetic Al addition dilutes the ferromagnetic Fe/Co/Ni additions. In this paper we discuss the magnetic and structural characterisation of the CoFeNi0.5Cr0.5-Alx composition and attempt to relate it to the interfacial energy.
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AIM: To assess coronary artery calcification (CAC) and vascular calcification in patients with pulmonary embolism (PE) and correlate this with mortality. MATERIALS AND METHODS: PE severity was quantified using computed tomography pulmonary angiography (CTPA) in 400 consecutive cases using the modified Miller score (1-5, mild; 6-11, moderate; 12-16, severe). Right ventricle strain was assessed using the right/left ventricle diameter (RV/LV) ratio. CAC score (CACS) was assessed using a four-point scale (CACS mild 1-3, moderate 4-8, severe 9-12) for each vessel and summed to give the total CACS. Follow-up for mortality was obtained at 3 years. RESULTS: PE severity was classified as mild in 48%, moderate in 21%, and severe in 32% of cases. The median modified Miller score was 6 (Interquartile range [IQR] 2, 14) and median total CACS was 2 (IQR 0, 7). All-cause mortality occurred in 128 (32%) patients. Patients with CAC were three times more likely to die than patients without CAC (Hazard ratio [HR] 2.96; 95% CI 1.84, 4.77; p<0.001), and patients with severe CAC were at the highest risk (HR 4.62; 95% CI 2.73, 7.83, p<0.001). Gender, modified Miller score and RV/LV ratio were not predictive of mortality. In multivariate analysis both CACS and age were independent predictors of 3-year all-cause mortality. Of the patients with CAC who died, the presence of coronary artery disease was only documented in 34 (32%). CONCLUSION: CACS is an independent predictor of all-cause mortality in patients with PE, and has important implications for subsequent patient management.
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Enfermedad Coronaria/mortalidad , Embolia Pulmonar/mortalidad , Calcificación Vascular/mortalidad , Anciano , Angiografía por Tomografía Computarizada , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/diagnóstico por imagen , Femenino , Humanos , Masculino , Embolia Pulmonar/complicaciones , Embolia Pulmonar/patología , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Calcificación Vascular/complicaciones , Calcificación Vascular/diagnóstico por imagenRESUMEN
Eye flukes are common infections of freshwater fish and their occurrence as metacercarial stages may occur non-randomly resulting in an asymmetrical distribution within the host eyes. However, from previous studies the presentation of bias by these trematodes lacks consistency suggesting that congenital asymmetrical effects are unlikely to be the cause and exogenous factors, such as environmental stress, may be more influential. The present study, undertaken over a 4-year period, investigates the impact of an extreme heatwave and drought on the annual bilateral asymmetry and occurrence of two eye fluke species (Diplostomum sp. in the lens and Tylodelphys sp. in the vitreous humour) from perch (Perca fluviatilis) and roach (Rutilus rutilus). The onset of the extreme climatic event resulted in a significant negative effect on the occurrence of the eye flukes. Bilateral asymmetry, which was present within both trematode species and hosts, appeared to be highly variable between eye fluke and fish species and also year of study. However, during the pre-drought period both host species demonstrated significant asymmetry for Tylodelphys sp. but not for Diplostomum sp. while during the drought this bias was reversed. The potential role of fluctuating asymmetry of fish hosts in structuring the bilateral asymmetry of eye flukes is discussed.
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Clima , Oftalmopatías/veterinaria , Enfermedades de los Peces/parasitología , Percas/parasitología , Trematodos/fisiología , Animales , Sequías , Inglaterra , Ojo/parasitología , Oftalmopatías/parasitología , Calor , Lagos/parasitologíaRESUMEN
Vertebrate hosts commonly harbour concurrent infections of different helminth species which may interact with each other in a synergistic, antagonistic or negligible manner. Direct interactions between helminths that share a common site in the host have been regularly reported, but indirect interactions between species that occur in different sites are rarely described, especially in fish hosts. Plerocercoids of Ligula intestinalis are common infections of the peritoneal (body) cavity of roach (Rutilus rutilus) in freshwater habitats. These larval cestodes can cause extensive systemic pathologies to the fish host, which in turn may alter its susceptibility as a target host for other helminth species. The present study, using an existing dataset, investigates the influence of L. intestinalis (ligulosis) on frequently occurring eyefluke infections in roach sampled from a lake in south-east England. The occurrence of two species of eyefluke (Diplostomum sp. and Tylodelphys sp.) in the roach population demonstrated no significant levels of interaction with each other. The prevalence but not mean intensity or abundance of Diplostomum sp. was significantly increased in ligulosed roach, while the incidence of Tylodelphys sp. remained unchanged. Analyses of bilateral asymmetry in the occurrence of eyeflukes in left and right eyes of infected fish demonstrate that Tylodelphys sp. shows significant asymmetry in non-ligulosed roach, which is not replicated in ligulosed individuals. In contrast, Diplostomum sp. shows no evidence of asymmetry in either ligulosed or non-ligulosed fish.
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Cestodos/fisiología , Infecciones por Cestodos/veterinaria , Cyprinidae/parasitología , Enfermedades de los Peces/parasitología , Helmintiasis Animal/parasitología , Trematodos/fisiología , Infecciones por Trematodos/veterinaria , Animales , Cestodos/aislamiento & purificación , Infecciones por Cestodos/parasitología , Coinfección/parasitología , Inglaterra , Interacciones Huésped-Parásitos , Lagos/parasitología , Trematodos/aislamiento & purificación , Infecciones por Trematodos/parasitologíaRESUMEN
Concurrent infections of helminths in vertebrates are widespread and may demonstrate synergistic, antagonistic or negligible levels of interactions between species that share a common site. However, indirect interactions between species that occur in different organs of a host are poorly documented, particularly in fish. Plerocercoids of Triaenophorus nodulosus are common liver infections of European perch (Perca fluviatilis). These larval cestodes cause extensive liver damage, resulting in systemic pathologies that include alteration of the physiochemical environment of the intestine. Perch harbour a wide range of intestinal helminths whose occurrence may be potentially influenced by the concurrent presence of T. nodulosus plerocercoids. The present study, using an existing dataset, investigated the effects of T. nodulosus on the infection levels of four common perch helminths - Acanthocephalus lucii, Camallanus lacustris, Proteocephalus percae and Bunodera luciopercae. The prevalences of A. lucii and C. lacustris were significantly reduced in fish infected by T. nodulosus, although the mean intensity of infections remained unaffected for any helminth species, while the mean abundance of C. lacustris was significantly reduced in plerocercoid-affected perch. Differences in site selection and individual interactions between the four helminth species in the intestine of T. nodulosus-infected and non-infected perch were rarely observed.
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Cestodos/fisiología , Infecciones por Cestodos/veterinaria , Enfermedades de los Peces/parasitología , Helmintiasis Animal/parasitología , Helmintos/fisiología , Intestinos/parasitología , Animales , Cestodos/genética , Cestodos/aislamiento & purificación , Infecciones por Cestodos/parasitología , Helmintos/genética , Helmintos/aislamiento & purificación , Percas/parasitologíaRESUMEN
Temperature is a key factor influencing the rate of biological processes of ectothermic animals and is intrinsically linked to climate change. Trematode parasites may be potentially susceptible to temperature changes and, in order to develop a predictive framework of their response to climate change, large-scale analyses are needed. In particular, the biology of the egg of all species is at some time influenced by environmental conditions. The present study uses Arrhenius activation energy (E*), a common measure of temperature-mediated reaction rates, to analyse experimental data from the scientific literature on the effects of temperature on the production, development and hatching of trematode eggs. Egg production declines at high temperatures, with habitat-specific climatic factors determining the optimal thermal range. Egg development, as is typical of invertebrates, shows a simple response to temperature, with minimal differences between mid- (35-60°) and low-latitude (<35°) species. Egg hatching demonstrates variable thermodynamics with high E* values at low temperature ranges and thermostability at mid-temperatures, before declining at high temperature ranges, with wide thermostable zones being a common feature. Comparisons between development and hatching indicate that these two parameters demonstrate different thermodynamical responses. The significance of these results in furthering our understanding of trematode egg biology under natural conditions is discussed.
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Temperatura , Trematodos/crecimiento & desarrollo , Cigoto/crecimiento & desarrollo , Animales , Trematodos/efectos de la radiación , Cigoto/efectos de la radiaciónRESUMEN
Photochemical reactions are essential to a large number of important industrial and biological processes. A method for monitoring photochemical reaction kinetics and the dynamics of molecular excitations with spatial resolution within the active molecule would allow a rigorous exploration of the pathway and mechanism of photophysical and photochemical processes. Here we demonstrate that laser-excited muon pump-probe spin spectroscopy (photo-µSR) can temporally and spatially map these processes with a spatial resolution at the single-carbon level in a molecule with a pentacene backbone. The observed time-dependent light-induced changes of an avoided level crossing resonance demonstrate that the photochemical reactivity of a specific carbon atom is modified as a result of the presence of the excited state wavefunction. This demonstrates the sensitivity and potential of this technique in probing molecular excitations and photochemistry.
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We present an optically induced remanent photostriction in BiFeO_{3}, resulting from the photovoltaic effect, which is used to modify the ferromagnetism of Ni film in a hybrid BiFeO_{3}/Ni structure. The 75% change in coercivity in the Ni film is achieved via optical and nonvolatile control. This photoferromagnetic effect can be reversed by static or ac electric depolarization of BiFeO_{3}. Hence, the strain dependent changes in magnetic properties are written optically, and erased electrically. Light-mediated straintronics is therefore a possible approach for low-power multistate control of magnetic elements relevant for memory and spintronic applications.
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Symbiotic bacteria are a common feature of many animals, particularly invertebrates, from both aquatic and terrestrial habitats. These bacteria have increasingly been recognized as performing an important role in maintaining invertebrate health. Both ecto- and endoparasitic helminths have also been found to harbour a range of bacterial species which provide a similar function. The part symbiotic bacteria play in sustaining homeostasis of free-living invertebrates exposed to anthropogenic pressure (climate change, pollution), and the consequences to invertebrate populations when their symbionts succumb to poor environmental conditions, are increasingly important areas of research. Helminths are also susceptible to environmental stress and their symbiotic bacteria may be a key aspect of their responses to deteriorating conditions. This article summarizes the ecophysiological relationship helminths have with symbiotic bacteria and the role they play in maintaining a healthy parasite and the relevance of specific changes that occur in free-living invertebrate-bacteria interactions under anthropogenic pressure to helminths and their bacterial communities. It also discusses the importance of understanding the mechanistic sensitivity of helminth-bacteria relationships to environmental stress for comprehending the responses of parasites to challenging conditions.
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Bacterias/crecimiento & desarrollo , Ecosistema , Helmintos/microbiología , Helmintos/fisiología , Simbiosis , Animales , Cambio Climático , Contaminación Ambiental , Estrés FisiológicoRESUMEN
Whilst most adult patients with acute lymphoblastic leukaemia will go into remission with standard induction chemotherapy, many will relapse. Response rates to standard salvage chemotherapy regimens are low and the outlook on relapse is very poor and associated with significant morbidity and mortality hence the need for newer targeted approaches. Inotuzumab ozogamicin (previously known as CMC-544) is an antibody-drug conjugate and consists of a monoclonal anti-CD22 antibody bound to calicheamicin. The target, CD22, is widely expressed on acute lymphoblastic leukaemia cells making it a potential therapeutic target. The calicheamicin is delivered intracellularly and causes leukaemia cell apoptosis. Overall response rates of 57% were observed in a Phase II study and the final results of a Phase III randomised controlled trial comparing this drug to the investigator choice 'standard of care' chemotherapy are eagerly awaited. Whilst initial results are promising, there have been concerns regarding liver toxicity and the incidence of veno-occlusive disease of the liver especially in patients who have previously received or go on to allogeneic stem cell transplant.
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Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos/uso terapéutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Adulto , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/farmacología , Antineoplásicos/efectos adversos , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Humanos , Inotuzumab Ozogamicina , Terapia Molecular Dirigida , Ensayos Clínicos Controlados Aleatorios como Asunto , RecurrenciaRESUMEN
AIM: To examine the number and nature of investigations performed for suspected pulmonary embolism (PE) in a large teaching hospital and the change in incidence and severity of PE over a decade. MATERIALS AND METHODS: In this retrospective study, all patients investigated for suspected PE using computed tomography pulmonary angiography (CTPA) or lung scintigraphy during 10 years to March 2012 were identified and their records reviewed. In the final year, all reportedly positive CTPA cases were reviewed and PE severity calculated, for comparison with similar historical data. RESULTS: From 2002 to 2012, total annual investigations for suspected acute PE increased by 163% (805 to 2121). CTPA increased by 325% (475 to 2019). Detection of PE increased by 121% (193 to 426 per annum), with stable distribution of severity scores. The positive scan rate decreased from 24% to 20%. The mean age of patients being investigated for PE increased from 56 to 63 years. CONCLUSIONS: Increased detection of PE is not due to disproportionate increase in small PEs, but to increased detection of PE of all severities. This finding supports the hypothesis that PE is more common in the general population than previously appreciated, which may represent an iceberg phenomenon of previously undetected disease.
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Arteria Pulmonar/diagnóstico por imagen , Embolia Pulmonar/epidemiología , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Hospitales de Enseñanza/estadística & datos numéricos , Humanos , Incidencia , Yopamidol/análogos & derivados , Pulmón/diagnóstico por imagen , Persona de Mediana Edad , Embolia Pulmonar/diagnóstico por imagen , Intensificación de Imagen Radiográfica , Cintigrafía , Radiofármacos , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Agregado de Albúmina Marcado con Tecnecio Tc 99m , Tomografía Computarizada Espiral , Adulto JovenRESUMEN
Temperature is an important factor influencing the biology of organisms and is intrinsically linked to climate change. The establishment of trematodes in target hosts is potentially susceptible to temperature changes effecting parasite infectivity or host susceptibility, and therefore in order to develop predictive frameworks of host-parasite dynamics under climate change large-scale analyses are required. The present study analyses the thermodynamics of the infectivity of larval trematodes including miracidia, cercariae and metacercariae from experimental data contained in the scientific literature using the Arrhenius critical incremental energy of activation (E*), an accurate measure of temperature-driven reaction rates. For miracidia and cercariae, infectivity increases as the temperature rises reaching a plateau over optimal thermal ranges before declining at higher temperatures. In contrast, metacercarial infectivity is at its greatest at low temperatures, declining with increasing temperature.
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Temperatura , Trematodos/fisiología , Infecciones por Trematodos/metabolismo , Animales , Cambio Climático , Susceptibilidad a Enfermedades , Interacciones Huésped-Parásitos/fisiología , Larva/fisiología , Infecciones por Trematodos/parasitología , Infecciones por Trematodos/transmisiónRESUMEN
SUMMARY Temperature is an important factor influencing the biology of ectothermic organisms and is intrinsically linked to climate change. Trematodes are potentially susceptible to temperature changes and in order to develop predictive frameworks of their responses to climate change large-scale analyses are needed. The present study, using the Q 10 value, analyses experimental data from the scientific literature on the effects of temperature on cercarial development and emergence across a wide range of temperature in low (⩽35°) and mid-latitude (36-60°) species. Temperature appears to have no significant effect on the rate of development of cercariae within molluscan hosts. Data on cercarial emergence, corrected to incorporate the minimum emergence temperature threshold (METT) and acclimation status, was found to be largely unaffected by temperature over optimum ranges of ≈20 °C (15-25 °C) for mid-latitude species and ≈25 °C (20-30 °C) for low-latitude species. In addition, a decline in emergence rates was shown at higher temperatures. These results are contrary to a previous study on the meta-analysis of cercarial emergence. Some evidence of strain-specific differences and thermostability over a wide temperature range for both cercarial development and emergence was apparent. The significance of these results in furthering our understanding of cercarial biology under natural conditions is discussed.
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Cercarias/fisiología , Moluscos/parasitología , Temperatura , Trematodos/fisiología , Animales , Cercarias/crecimiento & desarrollo , Calentamiento Global , Interacciones Huésped-Parásitos/fisiología , Termodinámica , Tiempo , Trematodos/crecimiento & desarrolloRESUMEN
Miracidia are short-lived, non-feeding (lecithotrophic) free-living stages of trematodes, whose survival is potentially influenced by temperature. Climate change may result in elevated temperatures affecting trematode transmission. Therefore understanding their thermobiology forms an important step in determining the future dynamics of parasite populations. An empirical relationship exists between the mean expected life span of lecithotrophic larvae and the half life of their population (t(0·5)) and therefore t(0·5) is a good indicator of glycogen utilization. In this study experimental data on the effects of temperature on miracidial survival were compiled from the scientific literature and evaluated in terms of metabolism using Q 10 and Arrhenius activation energy (E* or µ). Temperature poorly influenced survival/metabolism with all miracidia having distinct zone(s) of thermostability. Overall there were few differences in Q(10) and E* values between most species temperature ranges whilst there were only limited strain-specific variations in thermal responses of laboratory-maintained Schistosoma mansoni. Miracidia demonstrated a trend of greater thermal resistance than cercariae. In particular, comparative studies on 4 strains of the same species of miracidia and cercariae showed little correlation in thermal biology between the 2 life-history stages. The importance of these results for trematode transmission under global climate change is discussed.