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Red foxes play a crucial role in the life cycle and transmission of zoonotic pathogens, including Toxocara canis; however, comprehensive information on the prevalence of T. canis in red foxes (Vulpes vulpes) is lacking. In this meta-analysis we aimed to evaluate the global and regional prevalence of T. canis among red foxes. We searched PubMed, Scopus, and Google Scholar for studies reporting prevalence of T. canis in red foxes up to April 1, 2024. Using a random-effects model, we estimated pooled prevalences at global, regional, and national levels and assessed heterogeneity through subgroup and meta-regression analyses. The overall pooled global prevalence of T. canis infection in red foxes was 32.1% (95% CI, 28.5–35.6%), with the highest prevalence in Europe (34.6%, 30.9–38.3%) and the lowest in the Eastern Mediterranean (20.0%, 11.0–29.0%). In other regions, prevalences of Toxocara were as follows: Central Asia (33.1%, 26.8–39.4%), North America (23.6%, 10.6–36.6%), Western Pacific (21.3%, 5.2–37.4%), and Eastern Mediterranean & North Africa (20.0%, 11.0–29.0%). However, data from certain geographical regions are very limited (for example Greece, Austria, China and North Africa). Prevalence rates showed a decreasing trend over time. Subgroup analyses indicated higher prevalences in male red foxes (54.1%, 41.4–66.7%) compared to females (37.5%, 29.9–45.1%), and in juvenile red foxes (56.2%, 39.1–73.3%) compared to adults (33.4%, 23.2–43.6%). T. canis worm burdens were generally low, not exceeding an average of 4 worms per fox in most studies. Our findings reveal a substantial prevalence of T. canis infection in red fox populations worldwide (32.1%), highlighting their potentially significant role in perpetuating the transmission of infection to both companion animals and humans. Continued surveillance is essential to mitigate the risk of Toxocara transmission to companion animals and humans. However, a major remaining challenge is to assess the relative importance of the red fox as a contributor to environmental contamination with Toxocara ova. Further research is also needed to address study limitations and provide a complete global picture of T. canis epidemiology in red foxes and other wild animals, especially in underrepresented regions.

Recent outbreaks of various infectious diseases have highlighted the ever-present need to understand the drivers of the outbreak and spread of disease. Although much of the research investigating diseases focuses on single infections, natural systems are dominated by multiple infections. These infections may occur simultaneously, but are often acquired sequentially, which may alter the outcome of infection. Using waterfleas (Daphnia magna) as a model organism, we examined the outcome of sequential and simultaneous multiple infections with 2 microsporidian parasites (Ordospora colligata and Hamiltosporidium tvaerminnensis) in a fully factorial design with 9 treatments and 30 replicates. We found no differences between simultaneous and sequential infections. However, H. tvaerminnensis fitness was impeded by multiple infection due to increased host mortality, which gave H. tvaerminnensis less time to grow. Host fecundity was also reduced across all treatments, but animals infected with O. colligata at a younger age produced the fewest offspring. As H. tvaerminnensis is both horizontally and vertically transmitted, this reduction in offspring may have further reduced H. tvaerminnensis fitness in co-infected treatments. Our findings suggest that in natural populations where both species co-occur, H. tvaerminnensis may evolve to higher levels of virulence following frequent co-infection by O. colligata.

Toxocara species are cosmopolitan nematode parasites of companion, domestic and wild hosts. Of the 26 known species of Toxocara, only Toxocara canis and Toxocara cati are definitively zoonotic. The significance of wild carnivores as definitive hosts of T. canis and T. cati respectively, has received far less attention compared to domestic dogs and cats. Complex environmental changes have promoted increasing contact between wildlife, domestic animals and humans that can enhance the risk of pathogen spillover. This review lists a total of 19 species of wild canid host that have been shown to act as definitive hosts for T. canis and a total of 21 species of wild felid host. In general, the number of publications focusing on felid host species is fewer in number, reflecting the general paucity of data on T. cati. The wild canids that have received the most attention in the published literature include the red fox (Vulpes vulpes), the wolf (Canis lupus), and the golden jackal (Canis aureus). The wild felid species that has received the most attention in the published literature is the Eurasian lynx (Lynx lynx). Some non-canid and non-felid hosts also act as definitive hosts of Toxocara species. Certainly, red foxes would appear to be the most significant wild species in terms of their potential to transmit Toxocara to domestic dogs and humans via environmental contamination. This can be explained by their increasing population densities, encroachment into urban areas and their dietary preferences for a wide range of potential paratenic hosts. However, a major challenge remains to assess the relative importance of wild hosts as contributors to environmental contamination with Toxocara ova. Furthermore, one major constraint to our understanding of the significance of wildlife parasitism is a lack of access to samples, particularly from rare host species.

We investigated the relationship between the presence of helminth parasites in European badgers, and their tuberculosis (TB) status, culled as part of the bovine TB eradication programme in Ireland. Data on the worm burden or faecal egg or larval count was available for all helminth taxa recorded. Lymph node tissue samples were taken from the badgers and tested for TB. We then explored the correlation, in full-grown badgers, between the likelihood of M. bovis infection and both the prevalence and burden of certain helminth species. Specifically, our analyses focused upon the gastrointestinal species, Uncinaria criniformis and Strongyloides spp. We found that male badgers were more likely to have TB than female badgers, and that badgers infected with U. criniformis or Strongyloides spp. were more likely to have TB than badgers without such helminth infections. There was a suggestion that badgers with higher U. criniformis worm burdens were more likely to have TB than those with lesser burdens. Although our sampling protocols did not allow us to determine which infection came first, it strongly suggests that once badgers are infected with either gastrointestinal helminths or TB, they are likely to become coinfected. As Ireland works towards a national TB-free status, it will be important to appreciate the implications of such coinfection.

Abstract Background Prenatal maternal tobacco smoking is a predictor of child attention-deficit/hyperactivity disorder (ADHD) and is associated with offspring telomere length (TL). In this study, we examine the relationship between maternal prenatal smoking, infant TL, and maternal report of early childhood symptoms of ADHD. Methods One-hundred and eighty-one mother-infant dyads were followed prospectively for the infant’s first 18 months of life. Prenatal smoking was assessed from maternal report and medical records. TL was measured from infant buccal swab DNA obtained across the first 18 months of life. ADHD symptoms were obtained from maternal report on the Child Behavior Check List. Multiple regression models tested the relation between prenatal smoking and both ADHD symptoms and infant TL. Additional analyses tested whether the change in infant TL influenced the relation between prenatal smoking and ADHD symptoms. Results Sixteen percent of mothers reported prenatal smoking. Infant TL at 4, 12, and 18 months of age were correlated. Consistent with previous cross-sectional studies linking shorter offspring TL to maternal prenatal smoking, maternal prenatal smoking predicted greater telomere shortening from four to 18 months of infant age (β = − 5.797, 95% CI [-10.207, -1.386]; p = 0.010). Maternal depression was positively associated with both prenatal smoking (odds ratio (OR): 4.614, 95% CI [1.733, 12.282]; p = 0.002) and child ADHD symptoms (β = 4.713, 95% CI [2.073, 7.354]; p = 0.0006). To prevent confounding, analyses examined the relation between TL, ADHD symptoms, and prenatal smoking only in non-depressed mothers. In non-depressed mothers, infant TL attrition across the first 18 months moderated the relation between smoking and child ADHD. Conclusions The findings extend previous studies linking prenatal smoking to shorter infant TL by providing data demonstrating the effect on TL trajectory. The relation between prenatal smoking and early infant ADHD symptoms was moderated by the change in TL. The findings provide novel initial evidence suggesting that TL dynamics are one mechanistic pathway influencing the relation between maternal prenatal smoking and ADHD.

Dogs are an important part of life for many people. Dog ownership can confer various health benefits to their owners, but it also presents some risks. In order to establish if dog owners were aware of these risks, an online survey of dog ownership practices was carried out. The survey was open during the month of January 2022 and received 662 responses regarding 850 individual dogs. Overall, 52% of people reported deworming their dog between zero and twice a year, which is unlikely to reduce the risk of infection to humans. The majority of dog owners (71%) reported disposing of faeces correctly; however, when comparing urban and rural environments, 33% of those in rural environments did not dispose of their dogs’ faeces at all, compared with 3% of people in urban locations. People who obtained their dog during the pandemic brought their dog to the vet and dewormed them more frequently than those who obtained their dog before the pandemic. There were no differences in how faeces was disposed of between these groups. These results indicate that we, as researchers and veterinarians, have much work to do in terms of educating dog owners about the ways in which we can reduce the risk of infection to ourselves and our communities.

Abstract Many parasites migrate through different tissues during their life-cycle, possibly with the aim to enhance their fitness. This is true for species of three parasite genera of global importance, Ascaris, Schistosoma and Plasmodium, which cause significant global morbidity and mortality. Interestingly, these parasites all incorporate the liver in their life-cycle. The liver has a special immune status being able to preferentially induce tolerance over immunity. This function may be exploited by parasites to evade host immunity, with Plasmodium spp. in particular using this organ for its multiplication. However, hepatic larval attrition occurs in both ascariasis and schistosomiasis. A better understanding of the molecular mechanisms involved in hepatic infection could be useful in developing novel vaccines and therapies for these parasites.

Abstract Background Ascariasis is a neglected tropical disease that affects 800 million people worldwide. Whereas most people only experience light worm burden, some people experience heavy worm burdens even after several rounds of chemotherapy, a phenomenon known as predisposition. Such heavy infections are associated with more severe symptoms and increased chronic morbidity. Methods In order to investigate potential mechanisms that may explain the observed predisposition, we infected mice with the porcine ascarid Ascaris suum using an established mouse model with two different mouse strains, where the C57BL/6J strain is more susceptible to infection and therefore a model for heavy infection and the CBA/Ca strain is more resistant and thus a model for light infection. At day 7 post-infection we investigated the liver proteome, using shotgun mass spectrometry, of both infected and control mice of each strain. Results We identified intrinsic differences, between the two mouse strains, in both oxidative phosphorylation proteins and proteins involved in retinol metabolism. Additionally, we found differences between the two mouse strains in activation of the complement system, where the CBA/Ca strain has higher protein abundances for lectin pathway proteins and the C57BL/6J strain has higher protein abundances for complement inhibiting proteins. The CBA/Ca strain had a higher abundance of proteins involved in the activation of the complement cascade via the lectin pathway. In contrast, the C57BL/6J strain demonstrated a higher abundance of proteins involved in arresting the complement pathway. Conclusions We observed clear differences between the two mouse strains both intrinsically and under infection.

Coprological analysis is the most widely used diagnostic tool for helminth infection in both domestic and wild mammals. Evaluation of the efficacy of this technique is rare, due to the lack of availability of adult worm burden. Where information is available the majority of studies are in small ruminants and seldom in a wild host. This study of 289 wild badgers is the first to report the relationship between faecal egg/larval counts and adult worm burden in badgers whilst also evaluating the reliability of coprological analysis as a diagnostic tool for hookworm (Uncinaria criniformis) and lungworm (Aelurostrongylus falciformis) infection. The prevalence of hookworm and lungworm infection, as assessed through adult worm burden was 59.2% and 20.8% respectively. For both species of helminth, infection was consistently under-reported by coprological analysis compared to adult worm burden with a reported 41% sensitivity for hookworm and 10% for lungworm. A significant positive relationship was found between faecal counts and adult worm burden for both species of helminths. Additionally the density –dependent relationship often reported in helminth infection appears to be weak or non-existent in this study, up to the observed worm intensity of 500. Keywords: Badger, Helminth, Uncinaria, Aelurostrongylus, Worm burden, Egg/larval count

Background/Objectives Screening for nutrition risk in community-dwelling older adults increases the likelihood of early intervention to improve nutritional status, with short screening tools preferred. SCREEN-II-AB is a valid 8-item tool. The current study determines whether SCREEN-III, a proposed 3-item version, adequately classifies nutrition risk in comparison. Subjects/Methods Baseline data from the Canadian Longitudinal Study on Aging were used. Seventy-two percent (n = 24,456) of eligible participants (>55 years, complete SCREEN-II-AB) were included. Sensitivity and specificity of various SCREEN-III values compared with SCREEN-II-AB risk determined a nutrition risk cut-point and the proportion misclassified (False[-]) was calculated. Construct validity was tested against a composite variable summarizing outcomes associated with nutrition risk (e.g., self-reported health, hospitalization) using logistic regression adjusted for individual factors (e.g., marital status). Results A SCREEN-III cut-point of Conclusion The proposed version of SCREEN-III demonstrated construct validity, but misclassification of risk may be problematic; further validation of a 3-item version is recommended., Author(s): Jill M. Morrison [sup.1] , Celia V. Laur [sup.2] , Heather H. Keller [sup.1] [sup.3] Author Affiliations: (1) Department of Kinesiology, University of Waterloo, Waterloo, Canada (2) School of [...]