Reptiles are among the most diverse groups of animals, inhabiting nearly all continents and environments. Understanding their parasite biodiversity has garnered significant interest, particularly from a One Health perspective. Although the highly diverse reptile fauna of Iran, comprising 272 species i.e. 89 snakes (Serpentes), 171 lizards (Sauria), 8 turtles, 2 tortoises (Testudines), 1 crocodile (Crocodilia), and 1 worm-lizard (Amphisbaenia), there is a shortage of information about parasites. The present review is a compilation of 62 studies published from 1922 to August 2024. We present information on 56 species of reptiles from five groups (amphisbaenians, crocodiles, testudines, snakes, and lizards) and 98 parasitic taxa belonging to different protozoa and metazoa i.e. nematodes, cestodes, trematodes, acanthocephala, leeches, ticks, mites, and myiasis -producing flies. Although 63 taxa were diagnosed at the species level, 35 parasite taxa were only reported at the genus or family levels. Reviewing the literature, we found a paucity of information about endemic reptiles several of which are vulnerable species. Considering that some of the detected parasites e.g. Cryptosporidium and amoebae have serious clinical and/or public health threats molecular diagnostic techniques are needed for precise identification and understanding of the epidemiology and the potential zoonotic implications associated with parasites of reptiles. There is also a need to understand the exact distribution and host-parasite associations in different reptilian species present in Iran including the role of the reptiles as intermediate and reservoir hosts.
The caryophyllidean tapeworm Caryophyllaeus brachycollis (Janiszewska, 1953) is indigenous to the Lake Blidinje in the west-central part of Bosnia-Herzegovina where it infects chub Squalius tenellus (Heckel, 1843). Of 22 chubs examined, 45% were infected with C. brachycollis and a total of 912 specimens of this worm were counted. Histopathological and ultrastructural investigations were conducted on interface region between chub intestine and cestode scolex. Different sizes of lipid droplets in cestode tegument, in interface region and in chub enterocytes were observed. C. brachycollis lacks any specialized attachment organs and with an expanded, flattened scolex goes deep in mucosal folds and firmly attaches to them. In the epithelium of fish intestine, near the site of worm attachment, a high number of mucous cells and several rodlet cells were noticed. Indeed, within the intestinal tunica propria-submucosa, beneath the site of scolex attachment, numerous neutrophils and mast cells were encountered. Transmission electron microscopy of the apical part of the scolex of C. brachycollis showed the occurrence of a multicellular, syncytial glandular complex, the scolex produced membrane-bound secretory granules and their fibrillar contents discharged by merocrine and apocrine secretion onto the host-parasite interface. Our results are among the first to provide evidence on the sophisticated relationship between fish intestine and amorphous-undefinable substance produced by scolex glandular complex.
The Wildlife Malaria Network (WIMANET) is a groundbreaking multinational collaboration focused on studying vector-borne haemosporidian parasites in wildlife. Unlike human malaria, wildlife malaria is found on all continents except Antarctica, with parasites being transmitted by a range of vectors. The complexity and diversity of these parasites makes it necessary to have an interdisciplinary approach to understand and mitigate their impacts. Established in 2023 within the framework of COST-Action (European Cooperation in Science and Technology), WIMANET unites researchers from diverse scientific backgrounds to tackle critical questions about wildlife malaria on a global scale. This meeting report summarises the activities and plans resulting from the 1st meeting of WIMANET's six working groups, spanning the genetic and morphological identification of parasites to understanding the drivers of host-parasite-vector associations from individual to community levels. WIMANET's collaborative efforts aim to fill the knowledge gaps and foster large-scale research initiatives transcending local and regional boundaries.
Toxoplasma gondii infections in small mammals are important because they serve as source of infection for the felids who excrete environmentally resistant oocysts in their feces. Here, the authors sought evidence for T. gondii infection in shrews and rodents in Armenia for the first time. Toxoplasma gondii DNA was detected in tissues of trapped animals using a specific PCR targeting gene with a non-coding fragment length of 529 bp. Toxoplasma gondii DNA was detected in 15 out of 137 (10.9%) samples from small mammals from 6 different localities of Armenia for the first time.
Domestic dogs (Canis familiaris) and wild canids, including coyotes (Canis latrans) and red foxes (Vulpes vulpes), serve as definitive hosts for Dirofilaria immitis, a parasitic nematode causing the heartworm disease. Understanding infection risks in wildlife reservoirs in relation to environmental factors is crucial for assessing exposure risk in domestic dogs. The regional prevalence of D. immitis infection was estimated in trapped wild coyotes and red foxes across Québec, Canada. Spatial clusters of infection were detected using Kulldorff's spatial scan statistics. A series of logistic regression models predicting the D. immitis status in coyotes were built from heartworm development unit (HDU) estimates and cumulative precipitation variables over various time periods. Between October 2020 and March 2021, 421 coyotes and 284 red foxes were examined for the presence of D. immitis. The parasite was found in 43 coyotes and 1 red fox. A high-risk infection cluster was detected in coyotes in southwestern Québec. The best model included as sole predictor the average cumulative HDU contributing to risk of D. immitis in the three years preceding coyote capture. This model significantly predicted infection status with an area under the curve of 76.1%. The cumulative precipitation had no notable effect in any model. This study highlights a high prevalence of D. immitis in coyotes in Québec with regional differences correlated to temperature-derived predictors. The spatial risk of infection in this population likely represents the environmental risk of exposure to the parasite given that coyotes do not receive preventive treatment compared to domestic dogs. Our findings are important for veterinarians in the application of prevention strategies for heartworm disease in domestic dogs.
Myxobolus nagaraensis is a myxozoan parasite first reported in freshwater gobies (Rhinogobius spp.) from the Nagara River, Gifu Prefecture, Japan. Myxospores of M. nagaraensis form plasmodia in the visceral cavities of gobies, commonly presenting as distended abdomens. Although Rhinogobius is a common fish genus in Japan, details of M. nagaraensis, including genetic information, remain unknown. We compared the nucleotide sequences of the ribosomal RNA gene (rDNA) of M. nagaraensis from three different host species (R. fluviatilis, R. nagoyae, and R. similis) caught in three different rivers in Japan (Sakai, Sagami, and Kaname). The ITS region (ITS-1, 5.8S rDNA, and ITS-2) and large subunit (LSU) rDNA exhibited 49 and 55 variable sites, respectively. The highest nucleotide diversity was observed in the ITS region (0.00962), whereas that of the LSU rDNA was 0.00187. Differences in host species, rather than rivers, were a significant factor for genetic variation in both the ITS region (62.58%; P < 0.001) and LSU rDNA (55.22%; P < 0.01). Significant genetic variation was observed in M. nagaraensis from R. similis compared to R. fluviatilis (P < 0.001) or R. nagoyae (P < 0.001) from the same river. Such details are valuable for understanding parasite dispersal and its ecological impact on Rhinogobius hosts.
Some species within the family Plasmodiidae (Haemosporida) have been extensively studied due to their implications for human health. However, for other haemosporidians that infect wild animals the knowledge is limited. Species within the genus Polychromophilus have thus far been documented exclusively as hemoparasites of bats. Records of Polychromophilus are primarily from Africa, Europe, and Southeast Asia, with limited information available for the Americas. Here, we assessed the state of knowledge on Polychromophilus species infecting bats worldwide and searched for the presence of Polychromophilus in blood samples of neotropical bats from Colombia. We found a total of 65 records of Polychromophilus in 46 bat species belonging to the families Emballonuridae, Hipposideridae, Miniopteridae, Rhinolophidae, Rhinonycteridae, and Vespertilionidae worldwide, except for Antarctica. In the Americas, records of the genus Polychromophilus are exclusively from Vespertilionidae bats in Brazil, Colombia, the United States, and Panama. The morphological and molecular analyses of blood from 125 bats, belonging to 39 species and captured in seven localities within the departments of Arauca and Caldas (Colombia), confirmed the presence of Polychromophilus deanei in a silver-tipped myotis, Myotis albescens (Vespertilionidae). This finding represents the first morphological and molecular confirmation of P. deanei in the Americas. Additionally, it expands the knowledge on the diversity and distribution of Polychromophilus in Neotropical bats.