A Neglected Parasite: Macracanthorhynchus hirudinaceus, First Report in Feral Pigs in a Natural Park of Sicily (Southern Italy)

Morphometric, histopathological and molecular findings of Macracanthorhynchus hirudinaceus infection in wild boar (Sus scrofa) from continental Italy

Although Macracanthorhynchus hirudinaceus is a neglected acanthocephalan of suids occasionally responsible for severe infections in humans, the spread of wild boar (Sus scrofa) populations in Europe could promote the circulation. Herein, we report the first morphometric, histological and molecular characterization of a severe M. hirudinaceus infection in a boar from continental Italy. The boar's intestine displayed granulomatous enteritis due to 24 helminths (14 females, 10 males), identified as adults of M. hirudinaceus by a combined morphometric/molecular approach. The phylogenetic analysis of the cox1 gene revealed a close relationship of the M. hirudinaceus sequence type found herein with those from Hungary and insular Italy. The high haplotype diversity and low nucleotide diversity of M. hirudinaceus specimens would suggest its rapid demographic expansion in the Mediterranean basin. More research is needed to assess the presence of M. hirudinaceus in susceptible beetle species and the role of boars in the epidemiology of infection.

Squamata reptiles as a potential source of helminth infections when preyed on by companion animals

BACKGROUND

Squamate reptiles cohabiting with companion animals may represent a source of helminth infections, especially through predation by dogs and cats with an outdoor lifestyle.

METHODS

In order to assess the role of reptiles as intermediate/paratenic hosts of trophically transmitted helminths, synanthropic reptiles (n = 245) captured from different ecological settings (i.e., households, dog shelters, urban, peri-urban and rural areas or natural parks) of southern Italy were examined for endoparasites. Parasitic cysts (i.e., larval forms of acanthocephalans, cestodes and nematodes) and free helminths (i.e., adult nematodes and digeneans) were morphologically and molecularly identified, and statistical analysis was carried out to evaluate the correlations between reptiles, infections, and ecological settings.

RESULTS

Overall, 31% of reptiles were positive for at least one helminth, with Podarcis siculus (18.7%) and Tarentola mauritanica (8.1%) being the most frequently infected species. Among the parasites of medical interest, Joyeuxiella echinorhyncoides showed the highest prevalence (19.7%), followed by Diplopylidium acanthotetra (10.5%), Joyeuxiella pasqualei, Mesocestoides lineatus (5.6%) and Physaloptera sp. (3.9%). Macracanthorhynchus hirudinaceus was detected once. Podarcis siculus and T. mauritanica were associated with cestode infections.

CONCLUSIONS

The wide range of helminths detected here in reptiles living in sympatry with pets and the fact that many of these helminth species are parasitic and may infect companion animals (e.g., J. pasqualei, J. echinorhyncoides, D. acanthotetra, Physaloptera sp.) and humans (i.e., Macracanthorhynchus hirudinaceus, Mesocestoides lineatus) indicate the potential health risk associated with pets preying on these small vertebrates. Our results indicate the need for complementary investigations of trophically transmitted parasites in dogs and cats living in sympatry with reptiles.

Insights to helminth infections in food and companion animals in Bangladesh: Occurrence and risk profiling

Introduction

A better understanding of the epidemiology of helminths in animal hosts is important in order to ensure animal welfare, public health and food safety. The aim of this study was to explore parasitism in common animals in Bangladesh. Perception and understanding of animal owners regarding parasitic diseases management were also assessed.

Materials and methods

A total of 550 fecal samples were examined from common animals (cattle, goat, pig, chicken, dog, and cat) across three different areas of Bangladesh (Dhaka, Sylhet, and Chattogram) from January 2020 to March 2021. Associated risk factors were assessed through questionnaire surveys among 50 animal owners. Parasitological assessment was done using the combined sedimentation-flotation method, and factors associated with infection were modeled using mixed-effects logistic regression.

Results

Helminths including Toxocara sp., Spirometra sp., Capillaria sp., Trichuris sp., opisthorchiid, Ascaris suum, Fasciola sp., Paramphistomum sp., strongyles, hookworms, roundworms, taeniid, and acanthocephalans were detected in the examined animals, and overall prevalence was 59.3% (95% CI = 54.1–62.8). Parasites were found in 61.3% (245/400) of food animals and 54.0% (81/150) of companion animals. Animal owners have a good understanding of parasite infections; however, that knowledge was not being translated into practice. Logistic regression analysis showed that frequency of deworming, animal husbandry practice, contact with untreated animals, and treatment-seeking behaviors were significantly associated with parasitic infection.

Conclusion

Several types of zoonotic parasites are widely prevalent in animals of Bangladesh and pose a potential risk to human health. This study highlights the need to diagnose animal parasitic infection and intensified case management to avoid spillovers to animals and humans.

First molecular description of Macracanthorhynchus hirudinaceus in wild boars from Italy with pathomorphological and epidemiological insights

Macracanthorhynchus hirudinaceus is a zoonotic parasite affecting suids worldwide which are the definitive hosts for this helminth species. Macracanthorhynchus hirudinaceus is of significant economic and management concern due to its pathogenicity, causing intestinal obstruction and perforation in the definitive hosts. Current study is the preliminary investigation from Sardinia, Italy, reporting the pathomorphological findings and molecular characterization of M. hirudinaceus in the wild boars (Sus scrofa meridionalis). A total of 59 wild boars were examined showing acanthocephalan infection in 8 (13.6%) animals. In total, 49 parasites were collected with a mean intensity of 6.1. Comparatively higher infection levels were observed for males (16.7%) and young boars (14.3%); however, these epidemiological differences were statistically non-significant. Histopathological examination revealed the presence of a variable number of nodules (∼5 mm) in the intestine of M. hirudinaceus infested animals surrounded by a hyperemic-hemorrhagic halo. Several parasites were recovered from the intestinal lumen attached by the means of characteristic hooks showing necrosis in muscle layers. A moderate number of plump reactive fibroblasts and lesser numbers of fibrocytes were embedded with and at the borders of the inflammatory nodules in a moderate amount of homogeneous intensely eosinophilic fibrillary material rupturing the cell membrane. For molecular characterization, six isolated worms were amplified for the partial mitochondrial cox1 gene showing distinct interindividual variations. This first pathological and molecular description from southern Europe provided new knowledge about the diffusion of M. hirudinaceus in wild boars, furthering the research into the origin and transmission status of M. hirudinaceus in endemic localities.