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Background: Most insects are poikilotherms and ectotherms, so their body temperature is predicated by environmental temperature. With climate change, insect body temperature is rising, which affects how insects develop, survive, and respond to infection. Aging also affects insect physiology by deteriorating body condition and weakening immune proficiency via senescence. Aging is usually considered in terms of time, or chronological age, but it can also be conceptualized in terms of body function, or physiological age. We hypothesized that warmer temperature decouples chronological and physiological age in insects by accelerating senescence. To investigate this, we reared the African malaria mosquito, Anopheles gambiae, at 27 °C, 30 °C and 32 °C, and measured survival starting at 1-, 5-, 10- and 15-days of adulthood after no manipulation, injury, or a hemocoelic infection with Escherichia coli or Micrococcus luteus. Then, we measured the intensity of an E. coli infection to determine how the interaction between environmental temperature and aging shapes a mosquito's response to infection. Results: We demonstrate that longevity declines when a mosquito is infected with bacteria, mosquitoes have shorter lifespans when the temperature is warmer, older mosquitoes are more likely to die, and warmer temperature marginally accelerates the aging-dependent decline in survival. Furthermore, we discovered that E. coli infection intensity increases when the temperature is warmer and with aging, and that warmer temperature accelerates the aging-dependent increase in infection intensity. Finally, we uncovered that warmer temperature affects both bacterial and mosquito physiology. Conclusions: Warmer environmental temperature accelerates aging in mosquitoes, negatively affecting both longevity and infection outcomes. These findings have implications for how insects will serve as pollinators, agricultural pests, and disease vectors in our warming world. [ABSTRACT FROM AUTHOR]

Abstract Background Most insects are poikilotherms and ectotherms, so their body temperature is predicated by environmental temperature. With climate change, insect body temperature is rising, which affects how insects develop, survive, and respond to infection. Aging also affects insect physiology by deteriorating body condition and weakening immune proficiency via senescence. Aging is usually considered in terms of time, or chronological age, but it can also be conceptualized in terms of body function, or physiological age. We hypothesized that warmer temperature decouples chronological and physiological age in insects by accelerating senescence. To investigate this, we reared the African malaria mosquito, Anopheles gambiae, at 27 °C, 30 °C and 32 °C, and measured survival starting at 1-, 5-, 10- and 15-days of adulthood after no manipulation, injury, or a hemocoelic infection with Escherichia coli or Micrococcus luteus. Then, we measured the intensity of an E. coli infection to determine how the interaction between environmental temperature and aging shapes a mosquito’s response to infection. Results We demonstrate that longevity declines when a mosquito is infected with bacteria, mosquitoes have shorter lifespans when the temperature is warmer, older mosquitoes are more likely to die, and warmer temperature marginally accelerates the aging-dependent decline in survival. Furthermore, we discovered that E. coli infection intensity increases when the temperature is warmer and with aging, and that warmer temperature accelerates the aging-dependent increase in infection intensity. Finally, we uncovered that warmer temperature affects both bacterial and mosquito physiology. Conclusions Warmer environmental temperature accelerates aging in mosquitoes, negatively affecting both longevity and infection outcomes. These findings have implications for how insects will serve as pollinators, agricultural pests, and disease vectors in our warming world.

Many parasite species use multiple host species to complete development; however, empirical tests of models that seek to understand factors impacting evolutionary changes or maintenance of host number in parasite life cycles are scarce. Specifically, one model incorporating parasite mating systems that posits that multihost life cycles are an adaptation to prevent inbreeding in hermaphroditic parasites and thus preclude inbreeding depression remains untested. The model assumes that loss of a host results in parasite inbreeding and predicts that host loss can evolve only if there is no parasite inbreeding depression. We provide the first empirical tests of this model using a novel approach we developed for assessing inbreeding depression from field-collected parasite samples. The method compares genetically based selfing rate estimates to a demographic-based selfing rate, which was derived from the closed mating system experienced by endoparasites. Results from the hermaphroditic trematode Alloglossidium renale , which has a derived two-host life cycle, supported both the assumption and the prediction of the mating system model, as this highly inbred species had no indication of inbreeding depression. Additionally, comparisons of genetic and demographic selfing rates revealed a mixed mating system that could be explained completely by the parasite's demography (i.e., its infection intensities). [ABSTRACT FROM AUTHOR]

Due to the importance of trees in urban ecosystems, it is crucial to understand the distribution, prevalence, and intensity of parasitic mistletoe infection across urban landscapes. In this study, we aimed to understand how various tree-related factors (e.g., tree taxonomy, size, pruning history, nativity, foliage, density, and diversity) might influence mistletoe prevalence and infection intensity across a typical subtropical urban greenspace. We surveyed 6,012 trees representing 96 species, 76 genera, and 44 families across a large, urban university campus in a major Southwest Chinese city. In total, we found 353 mistletoe host trees (prevalence: 5.87%), largely concentrated on the eastern part of campus, partially due to the proximity of waterbodies and a large adjacent greenspace, as well as higher tree density. To understand how predictors affected the prevalence and intensity of mistletoe infection, we used a hurdle model fitting our zero-inflated count data. Four independent variables significantly affected the prevalence of mistletoe infestation, with three demonstrating positive correlations (crown width, tree density, and tree diversity). One variable (evergreen foliage) negatively correlated with mistletoe prevalence. However, only one factor was found to significantly affect mistletoe infection intensity (crown width, positively). Due to the variety of ecosystem services mistletoes provide, more studies are necessary to assess the impact of various mistletoe management strategies, especially on urban biodiversity. Highlights: Of 6,012 surveyed trees, 353 hosted mistletoes, but 50 of 96 species did not. Four tree-related factors affected mistletoe prevalence (3 positively/1 negatively). Only tree size (positively) affected infection intensity. [ABSTRACT FROM AUTHOR]

Occurrence of quiescent nymphophan of Hydrachna sp. attaching to the sternites and tergites of thorax and abdomen of water beetle (Hydrophilus sp.) and giant water bug (Lethocerus sp.) is reported for the first time from West Bengal and Odisha of India. After feeding from one to five weeks as a parasitic larva on its host, Hydrachna sp, stops feeding and enters a quiescent nymphophan (nymphochrysalid) stage of development in which the larva squeezes into its exoskeleton and forms a saclike structure where metamorphosis occurs. By the means of gnathoma, it remains attached to the host body, casts off its exoskeleton, and within a short time, the developing nymph can be seen within it. The nymph comes out of a slit in the exoskeleton and assumes a free-living existence. These nymphochrysalids ranged in length from 682.17 to 2112.45µm with lateral stripes adorning their external integuments. Body appeared to be bottle shaped with pointed or rounded posterior end. Preferences of water mites for insect host body parts and seasons, infection intensity and prevalence were reported. [ABSTRACT FROM AUTHOR]

A helminthological survey of three fish species (Perca fluviatilis, Stizostedion lucioperca and Esox lucius) from the lower section of the Dniprovske Reservoir (also known as Zaporizhzhia) revealed the presence of the dioctophymatid nematode Eustrongylides excisus (third stage larvae). The study was conducted in 2020 and 2021. It was found that the total prevalence of infection was more than 40%. The nematode was found in the liver, abdomen and muscles. Significant tissue lesions were observed in some fish specimens. They were visually accompanied by mechanical damage, oedema and inflammation. The intensity of infection in P. fluviatilis and S. lucioperca was 14.18 ± 0.81 and 12.69 ± 0.73, respectively. In turn, the intensity of infection in E. lucius had the lowest value 2.40 ± 0.41. The abdomen and muscles of P. fluviatilis and S. lucioperca were affected more than the liver. No statistically significant differences were found between the intensity of infection of the abdomen and muscles in P. fluviatilis. Furthermore, the musculature of S. lucioperca was more heavily infected than the abdomen. In E. lucius, nematodes were found only in the abdominal cavity. [ABSTRACT FROM AUTHOR]

The alveolate protist Perkinsus olseni infections impose considerable stresses on the host Manila clam Ruditapes philippinarum, often reducing their tissue weight due to the drain on energy resources. However, the relationship between condition factors and P. olseni infection exhibits inconsistency in different scenarios, as it is influenced by various factors such as environmental conditions, food availability, and reproductive conditions. To gain deeper insights, we surveyed Manila clams occurring on tidal flats in Anmyeondo Island, Cheonsu Bay to assess P. olseni intensity and its effects on the fitness of Manila clams. The Ray's fluid thioglycollate medium assay revealed that P. olseni infection in clams from inner Cheonsu Bay had considerably greater P. olseni intensities in May and September 2021 than those from outer Cheonsu Bay and reference sites (P < 0.05). Despite the high level of P. olseni infection, condition index (CI), a ratio of the flesh weight to the shell weight, in clams from inner Cheonsu Bay was also significantly higher than in clams from outer Cheonsu Bay and reference sites (P < 0.05). A noteworthy finding of this study was the positive association between P. olseni infection intensity and CI in clams, which suggests that despite the high parasite load, clams were able to maintain a higher CI, possibly due to the abundance of nutrients and organic matter present in the inner bay. The P. olseni infection intensities measured in September were significantly higher at most of the sampling sites in the inner and outer bay, which could be associated with the poor health condition of clams during a post-spawning period. These results highlight the complexity of bivalves' ecological relationships in Cheonsu Bay and offer new insights into their adaptability accompanied by other factors to parasite stressors. [ABSTRACT FROM AUTHOR]

Background The conventional diagnostic for Schistosoma mansoni infection is stool microscopy with the Kato-Katz (KK) technique to detect eggs. Its outcomes are highly variable on a day-to-day basis and may lead to biased estimates of community infection used to inform public health programs. Our goal is to develop a resampling method that leverages data from a large-scale randomized trial to accurately predict community infection. Methods We developed a resampling method that provides unbiased community estimates of prevalence, intensity and other statistics for S mansoni infection when a community survey is conducted using KK stool microscopy with a single sample per host. It leverages a large-scale data set, collected in the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) project, and allows linking single—stool specimen community screening to its putative multiday "true statistics." Results SCORE data analysis reveals the limited sensitivity of KK stool microscopy and systematic bias of single-day community testing versus multiday testing; for prevalence estimate, it can fall up to 50% below the true value. The proposed SCORE cluster method reduces systematic bias and brings the estimated prevalence values within 5%–10% of the true value. This holds for a broad swath of transmission settings, including SCORE communities, and other data sets. Conclusions Our SCORE cluster method can markedly improve the S mansoni prevalence estimate in settings using stool microscopy. [ABSTRACT FROM AUTHOR]

Abstract Background Migratory birds play an important part in the spread of parasites, with more or less impact on resident birds. Previous studies focus on the prevalence of parasites, but changes in infection intensity over time have rarely been studied. As infection intensity can be quantified by qPCR, we measured infection intensity during different seasons, which is important for our understanding of parasite transmission mechanisms. Methods Wild birds were captured at the Thousand Island Lake with mist nets and tested for avian hemosporidiosis infections using nested PCR. Parasites were identified using the MalAvi database. Then, we used qPCR to quantify the infection intensity. We analyzed the monthly trends of intensity for all species and for different migratory status, parasite genera and sexes. Results Of 1101 individuals, 407 were infected (37.0%) of which 95 were newly identified and mainly from the genus Leucocytozoon. The total intensity trend shows peaks at the start of summer, during the breeding season of hosts and during the over-winter season. Different parasite genera show different monthly trends. Plasmodium causes high prevalence and infection intensity of winter visitors. Female hosts show significant seasonal trends of infection intensity. Conclusions The seasonal changes of infection intensity is consistent with the prevalence. Peaks occur early and during the breeding season and then there is a downward trend. Spring relapses and avian immunity are possible reasons that could explain this phenomenon. In our study, winter visitors have a higher prevalence and infection intensity, but they rarely share parasites with resident birds. This shows that they were infected with Plasmodium during their departure or migration and rarely transmit the disease to resident birds. The different infection patterns of different parasite species may be due to vectors or other ecological properties. Graphical abstract

The purpose of the research is to determine the efficiency of coccidiostat combined with probiotic for treatment coccidiosis in rabbits in a comparative aspect.Materials and methods. Rabbits suffering from eimeriosis were treated with coccidiostat and probiotic. The anticoccidial drug of the benzeneacetonitrile group, Diclacox 2.5%, the active ingredient of which is diclazuril, and probiotic Mucinolextra, which is a freeze-dehydrated biomass of Bifidobacterium globosum, Enterococcus faecium, B. subtilis, and B. licheniformis at a concentration of 1010 CFU/g were used as preparations. Feces from the rabbits were examined every 3 days by the Fülleborn method to identify coccidia oocysts and determine the infection intensity and prevalence. On the first and last experiment days, the rabbits were weighed to assess the dynamics of live weight. The experiment duration was 15 days.Results and discussion. Coccidiostat Diclacox 2.5% combined with probiotic Mucinol-extra proved to be highly effective against coccidiosis in rabbits.

The purpose of the research is to study the infection of diurnal birds of prey of the order Falconiformes with helminths and to determine the helminth species composition by the example of the Noyev Kovcheg Conservation Nature’s Nursery in the Altai Territory.Materials and methods. We studied diurnal birds of prey of the order Falconiformes for helminthosis in the Altai Territory, in the Noyev Kovcheg Conservation Nature’s Nursery, in 2022. For the parasitological study of birds, we used laboratory methods of helminthocoprological studies: helminthoovoscopy and helminthoscopy. Species identification was determined by characteristic morphological features of helminth eggs, larvae and fragments. To assess the infeсtion with certain types of helminths, we used standard indicators for parasitological research, namely, infection prevalence and infection intensity amplitude.Results and discussion. In 58 studied diurnal birds of prey of the order Falconiformes, 8 helminth species were identified of which 6 nematode species, namely, Ascaridia galli, Tetrameres sobolevi, Capillaria caudinflata, Heterakis gallinarum, Trichostrongylus spp., and Singamus trachea; 1 trematode species, Strigea spp.; and 1 cestode species, Raillietina echinobothrida. These species occurred throughout all seasons of 2022.

Animal migration impacts organismal health and parasite transmission: migrants are simultaneously exposed to parasites and able to reduce infection for both individuals and populations. However, these dynamics are difficult to study; empirical studies reveal disparate results while existing theory makes assumptions that simplify natural complexity. Here, we systematically review empirical studies of migration and infection across taxa, highlighting key gaps in our understanding. Next, we develop a unified evolutionary framework incorporating different selective pressures of parasite–migration interactions while accounting for ecological complexity that goes beyond previous theory. Our framework generates diverse migration–infection patterns paralleling those seen in empirical systems, including partial and differential migration. Finally, we generate predictions about which mechanisms dominate which empirical systems to guide future studies. Our framework provides an overarching understanding of selective pressures shaping migration patterns in the context of animal health and disease, which is critical for predicting how environmental change may threaten migration. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Medical & Pharmaceutical Sciences is the property of Arab Journal of Sciences & Research Publishing (AJSRP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Avian endoparasites play important roles in conservation, biodiversity and host evolution. Currently, little is known about the epidemiology of intestinal helminths and protozoans infecting wild birds of Britain and Ireland. This study aimed to determine the rates of parasite prevalence, abundance and infection intensity in wild passerines. Fecal samples (n = 755) from 18 bird families were collected from 13 sites across England, Wales and Ireland from March 2020 to June 2021. A conventional sodium nitrate flotation method allowed morphological identification and abundance estimation of eggs/oocysts. Associations with host family and age were examined alongside spatiotemporal and ecological factors using Bayesian phylogenetically controlled models. Parasites were detected in 20.0% of samples, with corvids and finches having the highest prevalences and intensities, respectively. Syngamus (33%) and Isospora (32%) were the most prevalent genera observed. Parasite prevalence and abundance differed amongst avian families and seasons, while infection intensity varied between families and regions. Prevalence was affected by diet diversity, while abundance differed by host age and habitat diversity. Infection intensity was higher in birds using a wider range of habitats, and doubled in areas with feeders present. The elucidation of these patterns will increase the understanding of parasite fauna in British and Irish birds.

Background: Migratory birds play an important part in the spread of parasites, with more or less impact on resident birds. Previous studies focus on the prevalence of parasites, but changes in infection intensity over time have rarely been studied. As infection intensity can be quantified by qPCR, we measured infection intensity during different seasons, which is important for our understanding of parasite transmission mechanisms. Methods: Wild birds were captured at the Thousand Island Lake with mist nets and tested for avian hemosporidiosis infections using nested PCR. Parasites were identified using the MalAvi database. Then, we used qPCR to quantify the infection intensity. We analyzed the monthly trends of intensity for all species and for different migratory status, parasite genera and sexes. Results: Of 1101 individuals, 407 were infected (37.0%) of which 95 were newly identified and mainly from the genus Leucocytozoon. The total intensity trend shows peaks at the start of summer, during the breeding season of hosts and during the over-winter season. Different parasite genera show different monthly trends. Plasmodium causes high prevalence and infection intensity of winter visitors. Female hosts show significant seasonal trends of infection intensity. Conclusions: The seasonal changes of infection intensity is consistent with the prevalence. Peaks occur early and during the breeding season and then there is a downward trend. Spring relapses and avian immunity are possible reasons that could explain this phenomenon. In our study, winter visitors have a higher prevalence and infection intensity, but they rarely share parasites with resident birds. This shows that they were infected with Plasmodium during their departure or migration and rarely transmit the disease to resident birds. The different infection patterns of different parasite species may be due to vectors or other ecological properties. [ABSTRACT FROM AUTHOR]

Intraspecific variation in host susceptibility to individual parasite species is common, yet how these effects scale to mediate the structure of diverse parasite communities in nature is less well understood. To address this knowledge gap, we tested how host genetic identity affects parasite communities on restored reefs seeded with juvenile oysters from different sources—a regional commercial hatchery or one of two wild progenitor lines. We assessed prevalence and intensity of three micro- and two macroparasite species for 4 years following restoration. Despite the spatial proximity of restored reefs, oyster source identity strongly predicted parasite community prevalence across all years, with sources varying in their relative susceptibility to different parasites. Oyster seed source also predicted reef-level parasite intensities across space and through time. Our results highlight that host intraspecific variation can shape parasite community structure in natural systems, and reinforce the importance of considering source identity and diversity in restoration design. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Northwest A & F University - Natural Science Edition is the property of Editorial Department of Journal of Northwest A&F University (Natural Science Edition) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Novel infectious diseases, particularly those caused by fungal pathogens, pose considerable risks to global biodiversity. The amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd) has demonstrated the scale of the threat, having caused the greatest recorded loss of vertebrate biodiversity attributable to a pathogen. Despite catastrophic declines on several continents, many affected species have experienced population recoveries after epidemics. However, the potential ongoing threat of endemic Bd in these recovered or recovering populations is still poorly understood. We investigated the threat of endemic Bd to frog populations that recovered after initial precipitous declines, focusing on the endangered rainforest frog Mixophyes fleayi. We conducted extensive field surveys over 4 years at three independent sites in eastern Australia. First, we compared Bd infection prevalence and infection intensities within frog communities to reveal species‐specific infection patterns. Then, we analyzed mark‐recapture data of M. fleayi to estimate the impact of Bd infection intensity on apparent mortality rates and Bd infection dynamics. We found that M. fleayi had lower infection intensities than sympatric frogs across the three sites, and cleared infections at higher rates than they gained infections throughout the study period. By incorporating time‐varying individual infection intensities, we show that healthy M. fleayi populations persist despite increased apparent mortality associated with infrequent high Bd loads. Infection dynamics were influenced by environmental conditions, with Bd prevalence, infection intensity, and rates of gaining infection associated with lower temperatures and increased rainfall. However, mortality remained constant year‐round despite these fluctuations in Bd infections, suggesting major mortality events did not occur over the study period. Together, our results demonstrate that while Bd is still a potential threat to recovered populations of M. fleayi, high rates of clearing infections and generally low average infection loads likely minimize mortality caused by Bd. Our results are consistent with pathogen resistance contributing to the coexistence of M. fleayi with endemic Bd. We emphasize the importance of incorporating infection intensity into disease models rather than infection status alone. Similar population and infection dynamics likely exist within other recovered amphibian‐Bd systems around the globe, promising longer‐term persistence in the face of endemic chytridiomycosis. [ABSTRACT FROM AUTHOR]

Abstract Background Annual mass drug administration with praziquantel has reduced schistosomiasis transmission in some highly endemic areas, but areas with persistent high endemicity have been identified across sub-Saharan Africa, including Uganda. In these areas many children are rapidly reinfected post treatment, while some children remain uninfected or have low-intensity infections. The aim of this mixed-methods study was to better understand variation in water contact locations, behaviours and infection risk in school-aged children within an area with persistent high endemicity to inform additional control efforts. Methods Data were collected in Bugoto, Mayuge District, Uganda. Two risk groups were identified from a longitudinal cohort, and eight children with no/low-intensity infections and eight children with reinfections were recruited. Individual structured day-long observations with a focus on water contact were conducted over two periods in 2018. In all identified water contact sites, four snail surveys were conducted quarterly over 1 year. All observed Biomphalaria snails were collected, counted and monitored in the laboratory for Schistosoma mansoni cercarial shedding for 3 weeks. Results Children came into contact with water for a range of purposes, either directly at the water sources or by coming into contact with water collected previously. Although some water contact practices were similar between the risk groups, only children with reinfection were observed fetching water for commercial purposes and swimming in water sources; this latter group of children also came into contact with water at a larger variety and number of sites compared to children with no/low-intensity infection. Households with children with no/low-intensity infections collected rainwater more often. Water contact was observed at 10 sites throughout the study, and a total of 9457 Biomphalaria snails were collected from these sites over four sampling periods. Four lake sites had a significantly higher Biomphalaria choanomphala abundance, and reinfected children came into contact with water at these sites more often than children with no/low-intensity infections. While only six snails shed cercariae, four were from sites only contacted by reinfected children. Conclusions Children with reinfection have more high-risk water contact behaviours and accessed water sites with higher B. choanomphala abundance, demonstrating that specific water contact behaviours interact with environmental features to explain variation in risk within areas with persistent high endemicity. Targeted behaviour change, vector control and safe water supplies could reduce reinfection in school-aged children in these settings. Graphical Abstract

Dice snakes can be a paratenic host for a stage IV of Eustrongylides excisus, Jägerskiöld, 1909 larva due to specific diet of the snakes. The infection rate of E. excisus in Natrix tessellata (Laurenti, 1768) was studied in the basin of the middle and the lower Dnipro River in 2013-2017. We searched for nematodes in snakes from four sites: Prydniprovska Thermal Power Station, Majorova Balka, Zaporizhzhia; National Nature Park Velykyi Luh. The snakes from all studied areas had high prevalence of infection (more than 90 %). The lowest level of intensity (2.50 ± 0.60) and abundance (2.27 ± 0.58) were in ecosystems near Prydniprovska ?PP. There was no significant difference between infection parameters in snakes from other groups. Capsules with larva localized in the gastrointestinal tract, liver, muscles, and lung. The most infected was the gastrointestinal tract statistical analysis showed significant differences with other organs. The lowest infection was found in the lung. Environmental pollution of the Dnipro River waters with pesticides and other pollutants accompanied by a climate change may influence on the E. excisus life cycle that needs additional studies. [ABSTRACT FROM AUTHOR]

Dice snakes can be a paratenic host for a stage IV of Eustrongylides excisus, Jagerskiold, 1909 larva due to specific diet of the snakes. The infection rate of E. excisus in Natrix tessellate (Laurenti, 1768) was studied in the basin of the middle and the lower Dnipro River in 2013–2017. We searched for nematodes in snakes from four sites: Prydniprovska Thermal Power Station, Majorova Balka, Zaporizhzhia; National Nature Park Velykyi Luh. The snakes from all studied areas had high prevalence of infection (more than 90 %). The lowest level of intensity (2.50 ± 0.60) and abundance (2.27 ± 0.58) were in ecosystems near Prydniprovska ТPP. There was no significant difference between infection parameters in snakes from other groups. Capsules with larva localized in the gastrointestinal tract, liver, muscles, and lung. The most infected was the gastrointestinal tract, statistical analysis showed significant differences with other organs. The lowest infection was found in the lung. Environmental pollution of the Dnipro River waters with pesticides and other pollutants accompanied by a climate change may influence on the E. excisus life cycle that needs additional studies.

Background: Annual mass drug administration with praziquantel has reduced schistosomiasis transmission in some highly endemic areas, but areas with persistent high endemicity have been identifed across sub-Saharan Africa, including Uganda. In these areas many children are rapidly reinfected post treatment, while some children remain uninfected or have low-intensity infections. The aim of this mixed-methods study was to better understand variation in water contact locations, behaviours and infection risk in school-aged children within an area with persistent high endemicity to inform additional control eforts. Methods: Data were collected in Bugoto, Mayuge District, Uganda. Two risk groups were identifed from a longitudinal cohort, and eight children with no/low-intensity infections and eight children with reinfections were recruited. Individual structured day-long observations with a focus on water contact were conducted over two periods in 2018. In all identifed water contact sites, four snail surveys were conducted quarterly over 1 year. All observed Biomphalaria snails were collected, counted and monitored in the laboratory for Schistosoma mansoni cercarial shedding for 3 weeks. Results: Children came into contact with water for a range of purposes, either directly at the water sources or by coming into contact with water collected previously. Although some water contact practices were similar between the risk groups, only children with reinfection were observed fetching water for commercial purposes and swimming in water sources; this latter group of children also came into contact with water at a larger variety and number of sites compared to children with no/low-intensity infection. Households with children with no/low-intensity infections collected rainwater more often. Water contact was observed at 10 sites throughout the study, and a total of 9457 Biomphalaria snails were collected from these sites over four sampling periods. Four lake sites had a signifcantly higher Biomphalaria choanomphala abundance, and reinfected children came into contact with water at these sites more often than children with no/low-intensity infections. While only six snails shed cercariae, four were from sites only contacted by reinfected children. Conclusions: Children with reinfection have more high-risk water contact behaviours and accessed water sites with higher B. choanomphala abundance, demonstrating that specifc water contact behaviours interact with environmental features to explain variation in risk within areas with persistent high endemicity. Targeted behaviour change, vector control and safe water supplies could reduce reinfection in school-aged children in these settings. [ABSTRACT FROM AUTHOR]

Abstract Background Accurate quantification of infection intensity is essential to estimate infection patterns of avian haemosporidian parasites in order to understand the evolution of host-parasite associations. Traditional microscopy is cost-effective but requires high-quality blood smears and considerable experience, while the widely used semi-quantitative qPCR methods are mostly employed with ideal, laboratory-based golden samples and standard curves, which may limit the comparison of parasitemia from different laboratories. Methods Here we present a digital droplet PCR (ddPCR) protocol for absolute quantification of avian haemosporidians in raptors. Novel primers were designed that target a conserved fragment of a rRNA region of the mitochondrial genome of the parasites. Sensitivity and repeatability were evaluated compared to qPCR and other assays. Results This ddPCR assay enables accurate quantification of haemosporidian parasites belonging to Plasmodium, Haemoproteus and Leucocytozoon with minimum infection quantities of 10−5 (i.e. one parasite copy in 105 host genomes) without the use of standard curves. Quantities assessed by ddPCR were more accurate than qPCR using the same primers through reduction of non-specific amplification in low-intensity samples. The ddPCR technique was more consistent among technical duplicates and reactions, especially when infection intensities were low, and this technique demonstrated equal sensitivity with high correspondence (R 2 = 0.97) compared to the widely used qPCR assay. Both ddPCR and qPCR identified more positive samples than the standard nested PCR protocol for the cytb gene used for barcoding avian haemosporidians. Conclusions We developed a novel ddPCR assay enabling accurate quantification of avian haemosporidians without golden samples or standard curves. This assay can be used as a robust method for investigating infection patterns in different host-parasite assemblages and can facilitate the comparison of results from different laboratories.

The purpose of the research is to develop the method of disinfection of external environment objects against cysts Buxtonella sulcata in cattle.Materials and methods. Under the conditions of "Orlovskoe” OJSC of Shchyolkovsky District Moscow Region biological test for experimental infection was applied for determination of efficiency of Cystodez for disinfection on 30 calves at the age of 6 months, which were free of B. sulcata. Efficiency of disinfection in the course of prescribing different concentrations of Cystodez as well as 4% concentration of background drug of carbolic acid was determined based on the percentage reduction of generation B. sulcata cysts after the above stated drugs exposure and concentrations compared with infected control calves, which were prescribed 200 cysts/ml. During August–September 2017 efficiency of 4% Cystodez against B. sulcata cysts of cattle were tested by the mean of by artificial laying of B. sulcata cysts on control sites compared with the background drug of 4% carbolic acid within the exposure of 2 hours under the manufacturing conditions of OJSC named after Guryanov of the Kaluga Region.Results and discussion. Intensive efficiency of 3% concentration of Cystodez was 97.9%, and in 4 and 5% concentration the drug demonstrated 100 % efficiency. Results received during manufacturing testing of 4 % Cystodez at the dose of 0.5 l per 1 m 2 within the exposure of 2 hours show its high efficiency for disinfection against cysts of cattle B. sulcata. Intensive efficiency was 92.32% versus 75.6% efficiency of the 4% background drug of carbolic acid.

Background: Approximately 25% of the risk of Schistosoma mansoni is associated with host genetic variation. We will test 24 candidate genes, mainly in the Th2 and Th17 pathways, for association with S. mansoni infection intensity in four African countries, using family based and case-control approaches. Methods: Children aged 5-15 years will be recruited in S. mansoni endemic areas of Ivory Coast, Cameroon, Uganda and the Democratic Republic of Congo (DRC). We will use family based (study 1) and case-control (study 2) designs. Study 1 will take place in Ivory Coast, Cameroon, Uganda and the DRC. We aim to recruit 100 high worm burden families from each country except Uganda, where a previous study recruited at least 40 families. For phenotyping, cases will be defined as the 20% of children in each community with heaviest worm burdens as measured by the circulating cathodic antigen (CCA) assay. Study 2 will take place in Uganda. We will recruit 500 children in a highly endemic community. For phenotyping, cases will be defined as the 20% of children with heaviest worm burdens as measured by the CAA assay, while controls will be the 20% of infected children with the lightest worm burdens. Deoxyribonucleic acid (DNA) will be genotyped on the Illumina H3Africa SNP (single nucleotide polymorphisms) chip and genotypes will be converted to sets of haplotypes that span the gene region for analysis. We have selected 24 genes for genotyping that are mainly in the Th2 and Th17 pathways and that have variants that have been demonstrated to be or could be associated with Schistosoma infection intensity. Analysis: In the family-based design, we will identify SNP haplotypes disproportionately transmitted to children with high worm burden. Case-control analysis will detect overrepresentation of haplotypes in extreme phenotypes with correction for relatedness by using whole genome principal components.

The purpose of the research: to conduct tests of Microsal in composition of 2% medicated feed mixture, which can be prepared in the farm under new conditions of keeping fish in cages (ultimate extinction of heated discharge into heat sink and fish wintering in cages under ice). Materials and methods. Test of 2% medicated feed mixture was conducted at Cherepetskiy rybkhoz Joint Stock Company of Tula region on carp yearlings which were spontaneously infected by bothriocephalus. 4 experimental cages were selected at the 5th pontoon line where about 10 000 of yearling carps with average weighed quantity of 10 g were located. Total weight of fish in each cage was about 100 kg. Before medical and preventive fish processing from each testing cage off at 10 yearling carps had been caught and exposed to helminthological prosection to define extensity and intensity of fish infection by bothriocephalus. On the 6-th day after medical and preventive processing it was also conducted catching and helminthological prosection off at 10 yearling carps to define extenseffectiveness (EE, %) and intenseffectiveness (IE, %) of fish processing by 2% medicated feed mixture with Microsal. Results and discussion. Water temperature at the level of cages lines only by the end of May was 14.8°С because of cold spring. Content of solvable oxygen is 6.2 mg/l. Yearling carps by that time had tiny average weighed quantity and were greatly weakened. Fish infectiousness in cages No 5, 21, 25, and 36 was 40, 40, 50, and 40% respectively while average infection intensity of 1.25-2.0 cestode on one fish. After a single medical and preventive processing yearling carps by 2% medicated feed mixture with microsal (doses on AI 40 mg/kg) 100% processing efficiency was achieved in three cages. In the cage No 21 EE of deworming was 75.0% with intenseffectiveness 71.4%. For receiving high efficiency of medical and preventive fish processing in such type of cage fish farms it is necessary to increase the number of administration of medicated feed (3-5 times), whilst cutting content of microsal in medicated feed from 2% to 0.4-0.5%.

The purpose of the research is to study the species diversity of pulmonary helminths of wild animals in the Transbaikal Territory.Materials and methods. The collection of material was carried out in different regions of the Trans-Baikal Territory: Akshinsky, Kirinsky and Krasnochikoysky. In total, 17 elk, 32 Siberian roe deer, and 5 wolves were subjected to helminthological research. The studies were performed by the method of full and partial helminthological autopsy. At autopsy, the intensity and extent of the infection were determined. Faecal samples were studied using the Berman-Orlov method.Results and discussion. The pulmonary helminthosis of wild animals (elk, roe deer, wolf ) of the Transbaikal Territory were studied. Elk revealed the nematodes Dictyocaulus eckerti; the infection extensiveness (IE) was 41%, the infection intensity (II) – 28-76 sp. per head. In Siberian roe deer, nematodes Muellerius capillaris were detected, with IE of 18.7% and II 24-54 sp. per head. Nematodes Crenosoma vulpis (Rudolphi, 1819) were detected in wolves with IE 16.6% and II 38 sp. per head.

The exact prevalence of Sarcocystis spp. infection in animals slaughtered for food is unknown in Lithuania. Therefore, the present study was initiated to evaluate Sarcocystis spp. infection in the carcasses of cattle (n = 206), sheep (n = 61), pigs (n = 73) and horses (n = 72) raised in Lithuania for food. The prevalence and intensity of Sarcocystis spp. infection were assessed under light microscopy by analysing 1 g of stained and squashed muscle samples. All the investigated muscle types (oesophagus, diaphragm, heart, neck, jaw, back, leg and tongue) were found to have been infected with microcysts rather than with macrocysts. A high prevalence of infection was established in cattle (44.9-98.1%) and sheep (100%), whereas the prevalence of this infection in pigs (30.1-50.0%) and horses (34.7-63.9%) was considered to be moderate. Significant differences in the infection prevalence were detected in the majority of muscle groups of cattle and in some muscle groups of pigs and horses. Similarly, significant differences in the median (Md) intensity of infection were observed in the majority of the muscle groups of cattle (Md = 4-29) and sheep (Md = 21-73) and only in some muscle groups of pigs (Md = 4.5-16) and horses (Md = 1-3). Cases of intense infection (> 40 cysts in a sample) were relatively often detected in sheep (44.9%) and cattle (19.1%), and rarely in pigs (3.7%). Hence, based on the varying rates of infection in the examined samples, the infection was identified as being intense in sheep and cattle, moderate in pigs and low in horses.

Abstract Background Soil-transmitted helminth (STH) infections are highly prevalent in the Philippines. Mapping the prevalence and high-intensity of STH co-infections can help guide targeted intervention programmes to reduce morbidity, especially among vulnerable school-aged children. In this study, we aimed to predict the spatial distribution of the prevalence of Ascaris lumbricoides and Trichuris trichiura co-infection and infection intensity classes in the Philippines to identify populations most in need of interventions. Methods Data on STH infections from 29,919 individuals during the nationwide parasitological survey in 2005 to 2007 were included in the analysis. To geographically predict the prevalence of A. lumbricoides and T. trichiura co-infections and infection intensity classes, Bayesian multinomial geostatistical models were built including age, sex, environmental variables and a geostatistical random effect. The number of individuals co-infected and belonging to each of the infection intensity classes in 2017 was forecast by combining our predictive prevalence maps with population density maps. Results Our models showed that school-aged children (5–19 years) are most at risk of A. lumbricoides and T. trichiura co-infections and of moderate/high infection intensity compared to other age groups. We identified target provinces where the likelihood of STH-associated morbidity was highest: Luzon (Bulacan, Benguet, Cavite, Sorsogon, Metropolitan Manila, Pampanga and Rizal), the Visayas (Cebu, Iloilo, Leyte and Negros Occidental), and in Mindanao (Agusan Del Norte, Davao Del Sur, Davao Oriental, Lanao Del Sur, Maguindanao, Misamis Oriental, Sulu and Zamboanga Del Sur). Luzon had the highest estimated number of school-aged children with A. lumbricoides and T. trichiura co-infections (estimated total 89,400), followed by the Visayas (38,300) and Mindanao (20,200). Conclusions Our study provided epidemiological evidence to highlight national priority areas for controlling co-infections and high intensity infections in the Philippines. Our maps could assist more geographically targeted interventions to reduce the risk of STH-associated morbidity in the Philippines.

Abstract Background From 2011 to 2015, seven trachoma impact surveys in 150 districts across Amhara, Ethiopia, included in their design a nested study to estimate the zonal prevalence of intestinal parasite infections including soil-transmitted helminths (STH) and Schistosoma mansoni. Methods A multi-stage cluster random sampling approach was used to achieve a population-based sample of children between the ages of 6 and 15 years. Stool samples of approximately 1 g were collected from assenting children, preserved in 10 ml of a sodium acetate-acetic acid-formalin solution, and transported to the Amhara Public Health Research Institute for processing with the ether concentration method and microscopic identification of parasites. Bivariate logistic and negative binomial regression were used to explore associations with parasite prevalence and intensity, respectively. Results A total of 16,955 children were selected within 768 villages covering 150 districts representing all ten zones of the Amhara region. The final sample included 15,455 children of whom 52% were female and 75% reported regularly attending school. The regional prevalence among children of 6 to 15 years of age was 36.4% (95% confidence interval, CI: 34.9–38.0%) for any STH and 6.9% (95% CI: 5.9–8.1%) for S. mansoni. The zonal prevalence of any STH ranged from 12.1 to 58.3%, while S. mansoni ranged from 0.5 to 40.1%. Categories of risk defined by World Health Organization guidelines would indicate that 107 districts (71.3%) warranted preventive chemotherapy (PC) for STH and 57 districts (38.0%) warranted PC for schistosomiasis based solely on S. mansoni. No statistical differences in the prevalence of these parasites were observed among boys and girls, but age and school attendance were both associated with hookworm infection (prevalence odds ratio, POR: 1.02, P = 0.03 per 1 year, and POR: 0.81, P = 0.001, respectively) and age was associated with infection by any STH (POR: 1.02, P = 0.03). Age was also associated with reduced intensity of Ascaris lumbricoides infection (unadjusted rate ratio: 0.96, P = 0.02) and increased intensity of hookworm infection (unadjusted rate ratio: 1.07, P < 0.001). Conclusions These surveys determined that between 2011 and 2015, STH and Schistosoma mansoni were present throughout the region, and accordingly, these results were used to guide PC distribution to school-age children in Amhara.

A moderate increase in temperature is likely to enhance the impact of parasites on aquatic ecosystems. Thus, under higher temperatures, poikilothermic animals (e.g. fish) increase their activity, which can result in a more frequent encounter with parasites and higher infection risk. However, temperature increase may also trigger counteracting processes in ambient communities decreasing the risk of parasitic infections. For instance, the removal of free‐living stages of parasites by filter‐feeding organisms can increase with temperature and potentially mitigate the disease risk in ecosystems under temperature shift. We examined whether an enhanced parasite transmission under higher temperatures can be compensated by the increased removal of parasitic larvae by filter‐feeders. In addition, our study aimed to reveal the behavioral mechanism underlying the more successful transmission of the parasite at higher temperatures. We studied experimentally how temperature, behavior of fish hosts (rainbow trout), and presence of filter‐feeding mussels in the environment influence the infection success of trematode larvae (Diplostomum pseudospathaceum cercariae). We found that heating increased while the presence of filter‐feeding mussels in the environment decreased infection intensities in fish. However, the effect of mussel's presence was constant within the tested range of water temperatures (15–23°C), which suggests that it cannot compensate for the observed increased transmission of parasites with temperature increase. Fish activity before the exposure to parasites was positively related to the host's vulnerability to infection. However, fish activity only weakly correlated with temperature, therefore, it is unlikely to be the only factor influencing the infection success under warmer conditions. In general, we showed that the elimination of trematode larvae by filter‐feeders is unlikely to deter the potential effects of temperature increase on host–parasite interactions in temperate freshwater ecosystems. [ABSTRACT FROM AUTHOR]

Polypodium hydriforme is a parasitic cnidarian that develops within the eggs of acipenseriform fish in the Old and New Worlds. Currently regarded as monotypic, P. hydriforme has been studied largely in the context of caviar production in Russian sturgeon species. We report the first robust epidemiological study of P. hydriforme in North American acipenseriform fish. We sampled infection prevalences (in 2017 and 2018) and intensities (in 2017) during annual surveys of American Paddlefish, Polyodon spathula, caught during spawning migration in north‐eastern Oklahoma. Egg masses were characterized for the presence and intensity of P. hydriforme infection. Prevalences were similar in 2017 and 2018 (49% and 45%, respectively). Generally, a small number of eggs were infected per egg mass, but a few were heavily infected. Longer, heavier and older fish are more likely to be infected and to harbour more severe infections. In addition, infection is linked to decreases in roe fat weight independently of fish length, weight, age or roe weight. Infection thus diminishes Paddlefish energy reserves (roe fat) which could in turn impact host fitness. Our results raise questions about the impacts of infection on caviar production and Paddlefish conservation and suggest insights on infection dynamics and parasite strategies. [ABSTRACT FROM AUTHOR]

Nosema ceranae is an emerging pathogen of the western honey bee (Apis mellifera L.), and thus its seasonality and impact on bee colonies is not sufficiently documented for North America. This study was conducted to determine the infection intensity, prevalence, and viability of N. ceranae in >200 honey bee colonies during spring, summer, and fall, in a North American region. We also determined the relationship ofN. ceranae infectionswith colony populations, food stores, bee survivorship, and overwinter colony mortality. The highest rates of N. ceranae infection, prevalence, and spore viability were found in the spring and summer, while the lowest were recorded in the fall. N. ceranae spore viability was significantly correlated with its prevalence and infection intensity in bees. Threshold to high levels of N. ceranae infections (>1,000,000 spores/bee) were significantly associated with reduced bee populations and food stores in colonies. Furthermore, worker bee survivorship was significantly reduced by N. ceranae infections, although no association between N. ceranae and winter colony mortality was found. It is concluded that N. ceranae infections are highest in spring and summer and may be detrimental to honey bee populations and colony productivity. Our results support the notion that treatment is justified when infections of N. ceranae exceed 1,000,000 spores/bee. [ABSTRACT FROM AUTHOR]

The protozoan Perkinsus marinus has been associated with high mortality episodes of the eastern oyster Crassostrea virginica in the USA. The presence of P. marinus on the pleasure oyster Crassostrea corteziensis cultivated in two estuaries on the southeast coast of the Gulf of California was evaluated. Oysters were collected monthly (September 2016 to September 2017) and analyzed using Ray's fluid thioglycollate medium (RFTM) and polymerase chain reaction (PCR). Water parameters and oyster biometrics were also recorded. Pathogen prevalence increased over time from 0 to 100% in oysters from La Pitahaya, and from 0 to 83.33% in those from Bacorehuis. At both oyster farms, infection intensity was light (<1×104 parasites g-1 wet tissue), pathogen prevalence and infection intensity were correlated with oyster size and weight, and there was a strong correlation between P. marinus prevalence and intensity (La Pitahaya r = 0.91; Bacorehuis r = 0.82). The oysters that resulted positive for P. marinus by RFTM also were assayed using PCR. P. marinus presence was confirmed in 98.27% (114/116) of the oysters from La Pitahaya, and 95.83% (46/48) of those from Bacorehuis. The detection of P. marinus confirms that this pathogen is well established in the area with high expression during the warmer season. Despite the light infection intensity of this parasite at both sites, health surveillance of this bivalve in the region is highly advisable. [ABSTRACT FROM AUTHOR]

This study aimed to investigate whether mass drug administration (MDA) intervention has an equivalent effect on reducing the prevalence and intensity of Schistosoma haematobium infection regardless of the baseline values. A repeated cross-sectional survey was performed targeting students of 12 primary schools in Al Jabalain and El Salam districts of White Nile State, Sudan, at both 1 week before and 8 months after the MDA. Prior to the baseline survey, schoolaged children in Al Jabalain had received MDA interventions twice in 4 years, while those in El Salam had not. The baseline prevalence was 9.1% in Al Jabalain and 35.2% in El Salam, which were reduced to 1.8% and 5.5% at 8 months after the MDA, respectively. The corresponding reduction rates were 80.3% and 84.4%, not significant difference between both districts. However, changes in the geometric mean intensity (GMI) of egg counts were significantly different between both districts. The baseline GMIs were 14.5 eggs per 10 ml of urine (EP10) in Al Jabalain and 18.5 EP10 in El Salam, which were reduced to 7.1 and 11.2 EP10 after treatment, respectively. The corresponding reduction rates were 51.0% and 39.5%. In conclusion, MDA interventions were found to bring about similar relative reduction in prevalence regardless of the baseline value; however, the relative reduction in infection intensity was more salient in the district with a low baseline value for both prevalence and intensity. This clearly points to the importance of repeated MDA interventions in endemic areas, which will eventually contribute to schistosomiasis elimination. [ABSTRACT FROM AUTHOR]

Background: Accurate quantification of infection intensity is essential to estimate infection patterns of avian haemosporidian parasites in order to understand the evolution of host-parasite associations. Traditional microscopy is cost-effective but requires high-quality blood smears and considerable experience, while the widely used semi-quantitative qPCR methods are mostly employed with ideal, laboratory-based golden samples and standard curves, which may limit the comparison of parasitemia from different laboratories. Methods: Here we present a digital droplet PCR (ddPCR) protocol for absolute quantification of avian haemosporidians in raptors. Novel primers were designed that target a conserved fragment of a rRNA region of the mitochondrial genome of the parasites. Sensitivity and repeatability were evaluated compared to qPCR and other assays. Results: This ddPCR assay enables accurate quantification of haemosporidian parasites belonging to Plasmodium, Haemoproteus and Leucocytozoon with minimum infection quantities of 10−5 (i.e. one parasite copy in 105 host genomes) without the use of standard curves. Quantities assessed by ddPCR were more accurate than qPCR using the same primers through reduction of non-specific amplification in low-intensity samples. The ddPCR technique was more consistent among technical duplicates and reactions, especially when infection intensities were low, and this technique demonstrated equal sensitivity with high correspondence (R2 = 0.97) compared to the widely used qPCR assay. Both ddPCR and qPCR identified more positive samples than the standard nested PCR protocol for the cytb gene used for barcoding avian haemosporidians. Conclusions: We developed a novel ddPCR assay enabling accurate quantification of avian haemosporidians without golden samples or standard curves. This assay can be used as a robust method for investigating infection patterns in different host-parasite assemblages and can facilitate the comparison of results from different laboratories. [ABSTRACT FROM AUTHOR]

• We investigated details of the temporal dynamics of haemosporidian infection patterns in wild bird communities. • Infection patterns of avian haemosporidians vary seasonally and are associated with the life stages of hosts. • Most of the birds became infected while still in the nest or during the first weeks post-fledging. • Infection prevalence and intensity declined in adults as first independent juveniles of the respective species appeared. Infection patterns of avian haemosporidians result from the evolution of their associations with hosts, and can be shaped by multiple biotic factors. However, at the level of parasite species, few studies have investigated the details of the temporal dynamics of infection patterns in wild bird communities. We hereby studied a wild bird community in southern Sweden to investigate two generalist parasites (cyt b lineages PARUS1 and WW2) of the morphological species Haemoproteus majoris in their main host species (tits and warblers, respectively) to look for seasonal (spring to autumn) and age class related variation in infection patterns. For both lineages, we detected a similar temporal pattern in prevalence and infection intensity, with peak levels during the main nesting season in adults and a few weeks later in juveniles. Infections in juveniles were detected as soon as they started to be caught by mist nets, implying that they became infected when still in the nest or during the first weeks post-fledging. The initially high intensities in juveniles were followed by a significant decrease during the hatching year, emphasising the importance of studying haemosporidian infections in nestlings and fledglings. Both prevalence and infection intensity in adults increased from spring to early summer, either due to spring relapses or new infections. Both prevalence and infection intensity declined in adults at the time when independent juveniles of the respective species started to appear, suggesting that the rate of parasite withdrawal from blood exceeded the rates of new infections gained and relapses of previous infections. Prevalence in both juveniles and adults approached zero towards the end of the summer. [ABSTRACT FROM AUTHOR]

Parasites may play several critical functions in marine ecosystems, including possibly influencing introduction success or modifying the roles of non-indigenous species. Based on seasonally replicated sampling, we have investigated parasite communities and infection rates of the non-indigenous round goby Neogobius melanostomus in two localities in the NE Baltic Sea, characterised by different invasion trajectories. The parasite community of the fish was very rich, consisting of at least 24 native parasite species, with moderate mean infection intensity - 9.4 parasites per host. In total 78% of fish were infected with parasites, most frequently hosting 1-3 parasite species per fish. The trematode Diplostomum spathaceum had the highest prevalence (46%), while the acanthocephalan Corynosoma strumosum and the trematode Tylodelphys clavata had the highest infection intensity (mean 6.8 and 7.2, respectively). The seasonal dynamics of prevalence were similar in both localities, with the lowest number of infected fish being found immediately after winter with no clear patterns/differences between other seasons. Broadly similar patterns appeared both for species richness and infection intensity. Both localities displayed very similar patterns of occurrence frequency: both had a few parasite species which were specific to one locality and five species that occurred more frequently in one of the two localities. Binomial regression of the probability of infection identified season, total body length, and sex as significant predictors, but not the locality of sampling. The quantitative model revealed that infection intensity was positively linked to total body length and parasite species richness, and was on average 2.7 individuals higher in summer and autumn than in winter and spring. [ABSTRACT FROM AUTHOR]

The main goal of the research conducted in the Lednice chateau park was to map the current spectrum of host trees and shrubs. The aim of the investigation was also to record changes in the host species, namely between the years 1985 and 2016, and to get an overview of the extent and degree of mistletoe infection on the most significant tree species present in the park. Furthermore, the occurrence of mistletoe across the developmental stages of woody species was monitored. Apart from taxonomic changes also the quantitative extent and the degree of infection reported in the last 31 years, and the impact on the development stages of woody plants in the past 20 years were analysed. Among the most frequently infected taxa are currently: Acer campestre, Acer platanoides, Acer pseudoplatanus, Crataegus monogyna, Robinia pseudoacacia, Tilia cordata and Tilia platyphyllos. The average share of infected specimens of the above host species amounts to 34.28%. A distinctive change in frequency and infection degree was recorded in the aggregate spectrum of hosts. The presence of mistletoe was recorded in a total of 1,362 specimens (almost 12% of the trees growing in the area). Compared to 1985, the occurrence of mistletoe was newly recorded in a total of 13 families (+3), 19 genera (+5) and 42 species (+18). In Aesculus ×marylandica, Fraxinus biltmoreana, Magnolia hypoleuca ×tripetala or Malus ×moerlandsii, it was probably described for the first time ever. At the moment, the most existentially endangered taxon is Tilia cordata.

Abstract Objective To determined both prevalence and intensity of Schistosoma mansoni infections among schoolchildren attending primary schools in Jimma town, an urban setting, Southwest, Ethiopia. Results The prevalence of S. mansoni infections was 8.4%. S. mansoni infections were found in all 17 schools, but the school prevalence ranged from 1.7 to 26.7%. This variation in prevalence could be explained by the proximity of the schools to the river crossing the town and water bodies near the schools. Boys were more infected compared to girls (χ 2 = 31.587, P value = 0.001; 95% CI), and the infection rate increased as a function of age (χ 2 = 21.187; P value = 0.001; 95 %CI). The majority of the infection intensities were of low intensity (57%), the mean number of eggs per stool equal to 17 eggs per gram of stool. Based on the prevalence (8.4%) school children in Jimma Town is considered as a low risk of morbidity caused by S. mansoni (prevalence ≤ 10% according to WHO threshold), for which it is recommended to implement MDA once every 3 years which should be supplemented with health information to create awareness about Schistosomiasis transmission. Male students were more infected than females with majority of the infection intensity were low.

[Display omitted] • Perkinsus sp. infection was detected in Manila Clams, but not in the other species. • High infection intensity was identified in the cold season when CI values were high. • Some extrinsic factors alter the annual dynamics and pathogenicity of perkinsosis. Perkinsosis has been recognized as one of the major threats to natural and farmed bivalve populations, many of which are of commercial as well as environmental significance. Three Perkinsus species have been identified in China, and the Manila clam (Ruditapes philippinarum) was the most frequently infected species in northern China. Although the occurrence and seasonal variation of Perkinsus spp. have previously been examined, the pathological characteristics of these infections in wild Manila clams and sympatric species in China have seldom been reported. In the present study, the prevalence and intensity of Perkinsus infection in wild populations of Manila clams and 10 sympatric species from three sites were investigated by Ray's fluid thioglycolate medium (RFTM) assay seasonally across a single year. Perkinsus infection was only identified in Manila clams, with a high prevalence (274/284 = 96.48 %) and low intensity (89.8 % with a Mackin value ≤ 2, suggesting generally low-intensity infections) throughout the year. Heavily infected clams were mainly identified in Tianheng in January, which displayed no macroscopic signs of disease. An overview of the whole visceral mass section showed that the trophozoites mostly aggregated in gills and connective tissue of the digestive tract, to a lesser extent in the mantle and foot, and even less frequently in adductor muscle and connective tissues of the gonad. PCR and ITS-5.8S rRNA sequencing of 93 representative RFTM-positive samples revealed a 99.69 to 100 % DNA sequence identity to Perkinsus olseni. Unexpectedly, significantly higher infection intensities were usually identified in January and April when the Condition Index (CI) was relatively high. We propose that factors associated with the anthropogenic harvesting pressure and irregular disturbances should be responsible for the uncommon seasonal infection dynamics of perkinsosis observed in the present study. [ABSTRACT FROM AUTHOR]

Avian malaria and related haemosporidian parasites are responsible for fitness loss and mortality in susceptible bird species. This group of globally distributed parasites has long been used as a classical system for investigating host–parasite associations. The association between a parasite and its hosts can be assessed by the prevalence in the host population and infection intensity in a host individual, which, respectively, reflect the ability of the parasite to infect the host and reproduce within the host. However, the latter has long been poorly investigated due to numerous challenges, such as lack of general molecular markers and limited sensitivity of traditional methods, especially when analysing naturally infected birds. The recent development of genetic databases, together with novel molecular methodologies, has shed light on this long-standing problem. Real-time quantitative PCR has enabled more accurate quantification of avian haemosporidian parasites, and digital droplet PCR further improved experimental sensitivity and repeatability of quantification. In recent decades, parallel studies have been carried out all over the world, providing great opportunities for exploring the adaptation of haemosporidian parasites to different hosts and the variations across time and space, and further investigating the coevolutionary history between parasites and their hosts. I hereby review the most important milestones in diagnosis techniques of avian haemosporidian parasites and illustrate how they provide new insights for understanding host–parasite associations.

Background: The conventional diagnostic for Schistosoma mansoni infection is stool microscopy with the Kato-Katz (KK) technique to detect eggs. Its outcomes are highly variable on a day-to-day basis and may lead to biased estimates of community infection used to inform public health programs. Our goal is to develop a resampling method that leverages data from a large-scale randomized trial to accurately predict community infection., Methods: We developed a resampling method that provides unbiased community estimates of prevalence, intensity and other statistics for S mansoni infection when a community survey is conducted using KK stool microscopy with a single sample per host. It leverages a large-scale data set, collected in the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) project, and allows linking single-stool specimen community screening to its putative multiday "true statistics.", Results: SCORE data analysis reveals the limited sensitivity of KK stool microscopy and systematic bias of single-day community testing versus multiday testing; for prevalence estimate, it can fall up to 50% below the true value. The proposed SCORE cluster method reduces systematic bias and brings the estimated prevalence values within 5%-10% of the true value. This holds for a broad swath of transmission settings, including SCORE communities, and other data sets., Conclusions: Our SCORE cluster method can markedly improve the S mansoni prevalence estimate in settings using stool microscopy., Competing Interests: Potential conflicts of interest. All authors: No reported conflicts., (© The Author(s) 2023. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)

This paper is a survey of the parasite diversity, prevalence and infection intensity in anurans in diverse ecological settings in West Africa. The settings included natural habitats (rainforests, freshwater creeks, Guinea and Sudan savannas), monoculture plantations (cocoa, cotton and oil palm), urbanized and urbanizing rainforest biotopes and polluted environments due to oil industry activities. The natural habitats had higher amphibian species diversity, moderate parasite prevalence and low infection intensity, showing a balance in the host/parasite relationship. These habitats yielded most of the monogeneans, among which were new species. The freshwater creek biotope had low amphibian diversity, but hosts from this environment harbored several parasite taxa, a situation attributed to a prolonged wet season, high environmental humidity and persistent breeding pools for insect vectors in this area. The monoculture plantations were characterized by high parasite prevalence but lower infection intensity. For example, in the Pendjari Biosphere Reserve in Bénin Republic, the Agricultural Zone (AZ) had higher parasite prevalence values, while the National Park (NP) and Buffer Zone (BZ) had higher infection intensities. Higher prevalence was attributed to the single or combined effects of vector population explosion, immune-suppression by agrochemicals, nutrient enrichment and eutrophication from fertilizer use. The lower infection intensity was attributed to the inhibitory effect of the pesticide-contaminated environment on the free-living larval stages of parasites. The adverse effect of pesticide contamination was also evident in the lower infection intensity recorded in the anurans from the cocoa plantations at Ugboke in comparison to those from the pesticide-free village settlement. Urbanization reduced host diversity and numbers and increased the vector population, resulting in unusually high parasite prevalence and infection intensities at Diobu and Port Harcourt and high prevalence recorded for Ophidascaris larvae in the anurans of Evbuabogun. Oil pollution in the mangrove community reduced both host and parasite diversity; infection intensity was also low due to the adverse conditions confronting free-living stages of parasites in their development milieu. The high prevalence values obtained for monogeneans (Polystoma spp.) in Ptychadena spp. from Ogoniland was presumed to have resulted from host tadpole sequestration and exposure to high oncomiracidia burden in the few hospitable ponds. Also reviewed is the phenomenon of amphibian paratenism, a strategy on which many helminth parasites rely on for their trophic transmission to their definitive hosts.

We evaluated cause of injury and quantified levels of three potential mycoplasmal pathogens (Mycoplasma agassizii, Mycoplasma testudineum, and an emydid mycoplasma) in three-toed box turtles (Terrapene carolina triunguis) from the greater St. Louis, Missouri, US area, brought to and housed at the Wildlife Rescue Center (Ballwin, Missouri, US) in 2015 and 2016. We created a probebased quantitative PCR (qPCR) assay for the emydid mycoplasma, with a similar specificity and sensitivity as the existing qPCR assays for M. agassizii and M. testudineum. All three microbes have been implicated in the development of upper respiratory tract disease in turtles and tortoises. We assessed whether signs of respiratory disease, sex, type of trauma, or treatment (administration of antibiotics) affected the presence of pathogens. We found that the most common types of injury experienced by turtles (n=85) were due to motor vehicles and other types of machinery, and that injuries due to motor vehicles were the most severe. We found a 61% prevalence of emydid mycoplasma (n=28) but M. agassizii or M. testudineum were not detected. Prevalence of disease and antibiotic treatment was too low to statistically relate to levels of mycoplasma. Sex and type of trauma were not associated with levels of emydid mycoplasma. The box turtle population we sampled did not experience signs of respiratory disease due to the fairly widespread prevalence of emydid mycoplasma. However, mycoplasmal diseases can be pathogen load-dependent. The qPCR we designed can be used to assess levels of emydid mycoplasma in other emydid species, populations, and individuals, in which there might be a positive association between the microbe and expression of respiratory disease. [ABSTRACT FROM AUTHOR]

• All surveyed farms tested positive for Eimeria oocysts and strongyle-type eggs. • The intensity of coccidial infections did not differ in both types of farms. • The intensity of strongylid infections also did not differ in both types of farms. • The intensity of tapeworm infections differed significantly in both types of farms. • The trematode eggs were not identified at any of the farms. This study evaluated the burdens of parasitic protozoans and helminths in dairy goats in two types of farming system in the Czech Republic. We examined nearly 660 faecal samples collected at 14 conventional and 14 organic farms. All farms tested positive for Eimeria oocysts and strongyle-type eggs. The output of coccidial oocysts was highest (86 880 oocysts per gramme - OPG) at an conventional farm, whereas the shedding of nematode strongylid eggs was highest (7400 eggs per gramme - EPG) at an organic farm. The intensities of coccidial and strongylid infections, however, did not differ significantly between conventional and organic farms during our survey. Eimeria arloingi , E. alijevi , and E. ninakohlyakimovae were the most prevalent coccidial species. Trichostrongylus/Teladorsagia sp. and Haemonchus contortus were the most prevalent gastrointestinal nematodes, and Muellerius capillaris was the most common lungworm at farms of both types. Eggs of the tapeworm Moniezia were also identified, with prevalences of 14% at conventional farms and 43% at farms applying alternative agricultural practices. Intensity of tapeworm infections was significantly higher (p = 0.02) at organic farms (maximum EPG of 1580) than conventional farms (maximum EPG of 60). Trematodes were not detected at any of the farms. The intensity of most prevalent endoparasitic infections did not differ significantly between the farm types probably due to their similar practices of grazing management and drenching frequency of antiparasitic drugs. [ABSTRACT FROM AUTHOR]

The exact prevalence of Sarcocystis spp. infection in animals slaughtered for food is unknown in Lithuania. Therefore, the present study was initiated to evaluate Sarcocystis spp. infection in the carcasses of cattle (n = 206), sheep (n = 61), pigs (n = 73) and horses (n = 72) raised in Lithuania for food. The prevalence and intensity of Sarcocystis spp. infection were assessed under light microscopy by analysing 1 g of stained and squashed muscle samples. All the investigated muscle types (oesophagus, diaphragm, heart, neck, jaw, back, leg and tongue) were found to have been infected with microcysts rather than with macrocysts. A high prevalence of infection was established in cattle (44.9-98.1%) and sheep (100%), whereas the prevalence of this infection in pigs (30.1-50.0%) and horses (34.7-63.9%) was considered to be moderate. Significant differences in the infection prevalence were detected in the majority of muscle groups of cattle and in some muscle groups of pigs and horses. Similarly, significant differences in the median (Md) intensity of infection were observed in the majority of the muscle groups of cattle (Md = 4-29) and sheep (Md = 21-73) and only in some muscle groups of pigs (Md = 4.5-16) and horses (Md = 1-3). Cases of intense infection (> 40 cysts in a sample) were relatively often detected in sheep (44.9%) and cattle (19.1%), and rarely in pigs (3.7%). Hence, based on the varying rates of infection in the examined samples, the infection was identified as being intense in sheep and cattle, moderate in pigs and low in horses. [ABSTRACT FROM AUTHOR]