Abstract Six freshly dead adult great cormorant Phalacrocorax carbo sinensis (Blumenbach, 1798) were collected during the winter season of 2025 from the coast of Canneviè lagoon (Northern Adriatic Sea, Italy). All 6 P. carbo sinensis (prevalence 100%) were infected with nematodes of the genus Contracaecum Raillet and Henry, 1912, with the intensity of infection ranging from 39 to 550 worms per host (212.8 ± 80.7; mean ± s.e. ). From the same lagoon, 41 European seabass, Dicentrarchus labrax (L.), were examined for helminths and in 27 specimens (65%) L3 larvae of C. rudolphii were encountered in extraintestinal sites of the seabass. In this study, 40 adults and 30 larvae of C. rudolphii from cormorants and 40 nematode larvae from seabass were characterized at species level using the diagnostic key based on the Restriction Fragment Length Polymorphism of 2 ribosomal regions, the nuclear ITS and the mitochondrial rrnS (12S). Adult nematodes from cormorants were identified as Contracaecum rudolphii B 83.8% (31/37) and the remaining 16.2% (6/37) were C. rudolphii A . Of the 30 larvae recovered from bird stomach 84.2% (16/19) appeared to be C. rudolphii B and 15.7% (3/19) were C. rudolphii A and all parasites from the seabass were third stage larvae of C. rudolphii A . Histological sections of cormorant alimentary canal showed that the nematodes went into the depth of the gastric folds and induced detachment of epithelial cells and secretion of excessive mucus. Furthermore, near the worm site of attachment, different types of innate immune cells were documented.
Abstract This study describes Vairimorpha rumexii sp. nov., a newly identified microsporidian parasite infecting Gastrophysa viridula , the green dock leaf beetle, in northeastern Türkiye. Microscopic examination revealed 2 distinct spore types, with light microscopy and Giemsa staining confirming both disporoblastic and octosporoblastic sporulation cycles characteristic of the genus Vairimorpha . Transmission electron microscopy provided detailed insights into spore ultrastructure, including polar tube configuration, spore wall stratification and nuclear arrangement. Molecular characterization using partial small subunit ribosomal RNA (SSU rRNA) and RNA polymerase II gene sequences, combined with phylogenetic analyses (maximum likelihood and Bayesian inference), placed V. rumexii sp. nov. in a distinct clade, closely related to but genetically separate from Vairimorpha gastrophysae . Notably, pairwise comparison of SSU rRNA sequences revealed a genetic distance of 0.0608 between the 2 species, supported by 72 nucleotide substitutions and 32 deletions, clearly indicating molecular divergence. The integration of morphological, ultrastructural and multilocus molecular data robustly supports its taxonomic distinctiveness as a novel species. This discovery expands the known diversity of microsporidia associated with Chrysomelidae, highlights the value of integrative taxonomy in resolving cryptic species and contributes to the understanding of Türkiye’s microsporidian fauna, potentially informing future biological control strategies.
Abstract Micromammals are abundant in nature and have a significant role as reservoirs for various parasites and pathogens. Very little is currently known about Sarcocystis prevalence and species richness in wild micromammals from Mediterranean Spain. In the present study, a pool of heart, lungs, and brain of 371 individuals representing three species, Algerian mouse ( Mus spretus ), wood mouse ( Apodemus sylvaticus ), and white-toothed shrew ( Crocidura russula ), was screened for Sarcocystis using molecular methods. Animals were sampled across 4 seasons in both natural and agricultural habitats. Prevalence in white-toothed shrew (28%) was significantly higher than in wood and Algerian mouse (17% and 18%, respectively). The lowest prevalence occurred in autumn, whereas no significant differences were detected between habitats. Analysis of 28S rRNA sequences revealed 11 Sarcocystis lineages, with the highest lineage diversity observed in the Algerian mouse. Based on comparative sequence and phylogenetic analysis, most of these lineages are suspected to use snakes as definitive hosts (DHs), three are associated with birds, and the DHs for two lineages are likely mammals. Notably, cox1 sequences could not be used to confidently identify all lineages. Our results reveal substantial diversity of Sarcocystis in Mediterranean micromammals and provide new insights into their transmission cycles.
Udonellids are monopisthocotylan flatworms that occupy a unique epibiotic niche, attaching to parasitic copepods while parasitizing the fish host's epithelial surface. Despite their broad distribution, species diversity within the genus Udonella Johnston, 1835 remains underexplored, particularly in South African marine environments, where new species discoveries are essential for refining its phylogeny. This study presents the integrative description of Udonella umgibeli n. sp., a new epibiotic monopisthocotylan collected from Caligus tetrodontis Barnard, 1948, parasitizing the evileye blaasop, Amblyrhynchote honckenii (Bloch), off the coast of South Africa. Twelve specimens were recovered from 3 copepods infecting a single fish host. Morphological analyses revealed distinct diagnostic features, including body proportions, haptor size, gonad arrangement and caudal gland configuration, separating the new species from all known congeners. Molecular characterization based on partial 18S and 28S rDNA sequences supported species delimitation, with U. umgibeli n. sp. most closely related to U. australis Carvajal & Sep & uacute;lveda, 2002. Although 18S rDNA divergence was low, this is consistent with the marker's highly conserved nature. This study provides the first molecular characterization of an Udonella species from the southwestern Indian Ocean and the first COI mtDNA sequence for the genus, underscoring the importance of integrative taxonomy for resolving species boundaries in morphologically conservative parasites.
We discuss some of the major cerebral parasites responsible for neglected diseases affecting humanity, especially in low-income countries. The World Health Organization states that cerebral malaria caused by Plasmodium falciparum is responsible for over 20% of deaths, especially in paediatric age. In addition to microscopy and molecular techniques, diagnosis can also be made with fundus magnetic resonance imaging and retinal fluorescein angiography, which have recently proven useful for assessing and understanding the clinical status of brain malaria. Currently, the best available treatment is combination therapy with artemisinin derivatives. Experimental drugs that prevent the development of malaria and blood-brain barrier dysfunction will be discussed. Neurocysticercosis is the most common helminthic infection of the central nervous system and a major cause of acquired epilepsy in resource-limited countries. Imported cases are increasing in Europe. Neuroimaging supported by immunodiagnostic tests with purified parasite antigens is the most important diagnostic test. Clinical management includes antiparasitic treatment, antiepileptic drugs, anti-inflammatories and surgery for obstructive hydrocephalus. In cerebral hydatidosis, brain involvement occurs primarily in childhood. Diagnosis is usually made through clinical, laboratory and imaging tests. The opportunistic toxoplasmic encephalitis is due to reactivation and can still be observed in AIDS patients with low access to antiretroviral therapy. Less common cerebral parasitic diseases include schistosomiasis, toxocariasis and amoebiasis, of which primary amoebic meningoencephalitis (Naegleria fowleri) has a very high mortality rate and treatment remains challenging in the absence of new drugs. The modification of existing drugs using nanotechnology offers promising prospects in the development of therapeutic interventions against these parasitic diseases.
Abstract Urbanization and tourism are intensifying human–animal interactions, yet their implications for cross-species parasite transmission remain poorly understood. This study investigates behavioural and ecological mechanisms underlying parasite transmission dynamics across interconnected human, dog and macaque populations sharing the same urban and touristic environment at Swayambhunath Temple, Kathmandu. We assessed parasite prevalence, diversity and infection intensity, combining parasitological analyses, participant questionnaire and behavioural observations to evaluate how anthropogenic factors and host behaviours influence parasitism and potential cross-species transmission. Humans displayed practices that may increase transmission risk, including close animal interactions, food provisioning and limited hygiene measures. Parasite prevalence was highest in macaques and dogs compared to humans, with macaques exhibiting the highest parasite diversity. Several parasites occurred in more than 1 species; notably, Entamoeba spp. was detected across all 3 species, indicating shared exposure pathways and zoonotic potential. In dogs, neither social nor anthropogenic variables predicted parasite metrics, but parasite diversity was linked to self-scratching, an indicator of anxiety, suggesting environmental pathway as a key drive of parasite transmission. In macaques, parasite diversity was shaped by interactions between dominance rank, provisioning and grooming, highlighting the interplay between social dynamics and human influence. Overall, these findings show that urban and touristic environments not only facilitate direct pathogen exposure but also indirectly shape parasite infection risk through behavioural and social mechanisms. Integrating behavioural ecology with urban disease ecology is essential for understanding and managing zoonotic risks in densely shared human–domestic animal–wildlife systems, with important implications for public and animal health and urban biodiversity management.
