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

Abstract

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 nonsignificant. 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.

Comparative Analysis of Ascaris suum and Macracanthorhynchus hirudinaceus Infections in Free-Ranging and Captive Wild Boars (Sus scrofa) in Hungary

“…The Sardinian studies showed the smallest differences in incidence; the difference was only −0.75% (Tables 4-6). Cameroon pig farm 0.2% 2022 [35] Italy (Sardinia) woodland area wild boar 13.6% 2022 [45] Brazil woodland area wild boar 1.04% 2023 [38] Research data on M. hirudinaceus from different parts of the world. Occurrence of A. suum and M. hirudinaceus by country, differences compared to Hungarian data.…”

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

“…hirudinaceus in P . siculus is unprecedented and may be explained by the high prevalence of this zoonotic helminth in wild boar and intermediate hosts from the same area [ 65 , 66 ]. Although little is known about the role of reptiles as paratenic hosts of M .…”

“…To date, human cases of accidental infection through the ingestion of intermediate/paratenic hosts parasitized by M . hirudinaceus have been described mostly from other countries (i.e., Morocco, Argentina, Iran, and Tunisia) [ 66 ].…”

A molecular and ecological study of Macracanthorhynchus ingens (von Linstow, 1879) (Acanthocephala: Archiacanthocephala), in its paratenic and definitive hosts in southeastern Mexico and the Eastern USA

“…At present, the genus includes four species: M. hirudinaceus (Pallas 1781) Travassos 1917 (type species), M. catulinus Kostylew 1927, M. rinaceid Dollfus 1953 and M. ingens (von Linstow 1879) Meyer 1932 (Amin, 2013 ). Species of Macracanthorhynchus have been the target of numerous studies related to their ecology, host-parasite relationships, pathogenicity, taxonomy, and systematics (Schmidt, 1971 ; Near et al, 1998 ; Richardson, 2005 , 2014 ; García-Varela & Nadler, 2005 ; Kennedy, 2006 ; Migliore et al, 2021 ; Dessì et al, 2021 ). Macracanthorhynchus ingens was described from the intestine of a racoon ( Procyon lotor Linnaeus) from North America (see Richardson, 2014 ), and since then this acanthocephalan has been recorded in other definitive hosts such as black bear ( Ursus americanus Pallas), domestic dog ( Canis familiaris Linnaeus), coyote ( Canis latrans Say), hog-nosed skunk ( Conepatus leuconotus Lichtenstein), eastern striped skunk ( Mephitis mephitis Schreber), mink ( Neovison vison Schreber), hairy-tailed mole ( Parascalops breweri Bachman), spotted skunk ( Spilogale gracilis Merriam) and gray fox ( Urocyon cinereoargenteus Schreber) in diverse countries such as Canada, United States, Mexico, Nicaragua and Colombia (García-Varela & Nadler, 2005 ; Richardson, 2014 ; Richardson et al, 2017 ; Hartnett et al, 2018 ).…”