Search Results (82)

Although bats can serve as reservoirs for several viruses and bacteria, there is limited knowledge regarding the diversity of apicomplexan protozoan belonging to the Piroplasmida and Haemosporida orders within this group of mammals. The present study aimed to investigate the occurrence and phylogenetic assessment of piroplasmids and hemosporidians in spleen samples collected from 229 vampire bats (228 Desmodus rotundus and 1 Diaemus youngii) in the states of Pará, Roraima, Amapá, and Amazonas, northern Brazil. Out of 229 bat spleen samples, 43 (18.77%) tested positive in a nested PCR for piroplasmids based on the 18S rRNA gene. Thirteen sequences (ranging from 474 to 828 base pairs) of the partial 18S rRNA gene showed 91.04–100% identity to Theileria sp., Babesia sp., and Piroplasmida previously detected in deer, tapirs, opossums, and crab-eating raccoons. The phylogenetic analysis based on the near-complete 18S rRNA gene positioned the obtained sequences from three D. rotundus in distinct clades (Theileria sensu stricto, Tapirus terrestris, and “South America Marsupialia”). All bat spleen DNA samples tested negative in a nested PCR assay for hemosporidians based on the cytB gene. The present study reported, for the first time, the presence Babesia sp. and Theileria sp. DNA in D. rotundus. The distinct positioning of the 18S rRNA gene sequences within different clades demonstrates the occurrence of different piroplasmid species in vampire bats. Full article

Nematodes of the genus Kiluluma (Strongylidae, Cyathostominae) parasitize African rhinoceros. We describe the case of a one-year-old male white rhinoceros calf that presented with colonic inflammation and hemorrhage at necropsy. The animal had died following a neurological episode. We recovered and identified adult nematodes from the colon using morphology and ITS2 gene sequences as Kiluluma ceratotherii. We also generated nuclear ITS1, 5.8S, ITS2, and mitochondrial cox1 sequences for future studies and deposited them in GenBank (OR142644–OR142653). Since the animal was born in the same zoo and never transported, infection likely originated within the herd. This is the first report of this nematode from a white rhinoceros in the United States. Full article

Bubaline sarcocystosis, caused by Sarcocystis levinei, is worldwide in distribution. Yet, very limited reports are available across the globe on the phylogenetic aspects of this particular Sarcocystis spp. Virtually no literature is available on its molecular aspects from India. Thus, the present study was designed to phylogenetically characterize the various isolates of S. levinei based on 18S rRNA and cox 1 mitochondrial genes. A total of 11 isolates of S. levinei from Northern India were characterized for 18S rRNA (MG957189-MG957199) and cox 1 (MH255771-MH255781) genes. PCR products were cloned, sequenced, and compared with other sequences across the world. A phylogenetic tree was constructed based on the maximum likelihood (ML) method. Phylogenetic analysis placed S. levinei and S. cruzi into two monophyletic sister groups. An appreciable amount of genetic variability was noticed between various S. levinei sequences for both the gene loci. A total of three haplotypes were noticed for each gene. The generated sequences showed 99.8–100.0% and 99.7–100.0% nucleotide homologies within themselves with regard to the 18S rRNA and cox 1 genes, respectively. Few of the studied sequences showed marked similarity and closeness with the Egyptian sequences than their Indian counterparts. This is the first report of molecular characterization and sequence phylogenetic study of S. levinei from India. Full article

Thread herrings (Opisthonema spp.) are economically important fish species in the Tropical Eastern Pacific. Knowledge of the parasitofauna of commercially exploited species is useful as it can increase our understanding of fish biology and ecology. However, our knowledge of the parasites of Opisthonema spp. is limited. During a fisheries exploration survey in April 2022, samples of Opisthonema bulleri and O. libertate were collected from three oceanographic stations in the Gulf of Tehuantepec in the Mexican Pacific. Parasitological analysis of these materials uncovered four parasite species: Myosaccium ecaude (Trematoda), Cribromazocraes sp. (Monogenea), Pseudoterranova sp. (Nematoda), and an unidentified crustacean of the family Pennellidae (Copepoda). All these species appeared rarely, except for M. ecaude, which reached a prevalence of 100%. The median intensity of M. ecaude infection was significantly higher in O. bulleri than in O. libertate. We analyzed the relationship between parasitic infection intensity and three host traits (fork length, body weight, and age). Only body weight showed a significant positive association with intensity. Future studies are required to analyze the possible effects of seasonality, locality, and host ontogeny on the occurrence of M. ecaude in thread herrings in the Tropical Eastern Pacific. Full article

Malaria is one of the most important neglected diseases in the world, and Brazil has the largest number of cases on the American continent. In Brazil, this disease is considered to be endemic in the Amazon region, although malaria lethality in extra-Amazonian regions is higher. Recently, it has been shown that malaria cases of autochthonous origin are not uncommon in the southeastern states. Among these states, Espírito Santo (ES) has the highest percentage of reported cases. This study aimed to describe the epidemiological profile and main factors that contribute to the incidence of malaria cases in this region, which corresponded to 4155 notifications in the 2007–2017 period based on data obtained from the Special Center for Epidemiological Surveillance of Espírito Santo. The most affected group was males aged around 40 years old, and most of the cases registered were of autochthonous origin. The number of malaria cases decreased during the period 2007–2017. Among the causative species, P. vivax was predominant, and it was followed by P. falciparum as the second most common species of all malaria cases. The main cities of ES presented high records of malaria disease, with high numbers of malaria cases in Santa Tereza, Domingos Martins, Alfredo Chaves, Santa Leopoldina, and Marechal Floriano. It is up to the local governments to advise the population about the epidemiological situation and to standardize medical care for individuals with suspected malaria. Full article

In January 2020, a mortality event was documented in endangered Pallid Sturgeon (Scaphirhynchus albus) at the Neosho National Fish Hatchery (Neosho, MO, USA). Moribund fish appeared emaciated, with hemorrhages on the fins and rostrums. Mortality steadily increased, prompting an investigation into the cause. No viral or bacterial pathogens were detected; however, a high number of the novel Gyrodactylus sp. was identified on the fins and body surface of the affected fish. Treatment of the parasites with a formalin product was effective, and mortality decreased. Herein, we describe the novel species Gyrodactylus conei using a combination of morphological and molecular data. Due to the listing of the host as an endangered species, the concept of parasite conservation is also discussed. Full article

Acanthamoeba keratitis (AK) is a rare cornea disease caused by species of the Acanthamoeba genus. The antifungal voriconazole blocks the ergosterol synthesis in the protozoan membrane and is active against the cysts and trophozoites of Acanthamoeba spp. Due to the low stability of voriconazole, its options for eye drops are scarce. This study aimed to investigate the stability of the biological activity of voriconazole against two strains of Acanthamoeba castellanii and one clinical isolate from a patient with AK. To evaluate the stability of the biological activity of voriconazole, strains of A. castellanii (ATCC 50492) were exposed to different periods and voriconazole concentrations stored at 4 °C for 7, 15, and 30 days. The cytotoxicity assays were performed using SIRC (ATCC CCL-60™) cell line. The results indicated the amoebicidal effect of voriconazole against Acanthamoeba spp. within 24 h and 48 h of exposure, and the voriconazole solution was stable and retained antiamoebic activity when stored at 4 °C for up to 30 days. In the cytotoxicity test, the result demonstrated low cytotoxicity of the drug to the corneal rabbit cell line. However, there is a need to carry out further synergistic effects with other antiamoebic drugs and then in vivo experiments in the AK animal model. Full article

To date, information on Cryptosporidium spp. infection status among people and wild animals living at the wildlife-human interface such as Queen Elizabeth National Park (QENP) is scarce. The aim of this study is to document the molecular detection of Cryptosporidium spp. in wild animals, and people, around QENP in the Kasese District. A total of 308 patients from four health centres and 252 wildlife animals from six species across 13 sampling areas were analysed microscopically and with PCR for Cryptosporidium spp. detection. The parasitological and molecular prevalence of Cryptosporidium spp. in humans was 40% and 53%, respectively; Kasenyi Health Centre recorded the highest percentage of positive stool samples for both tests. Wildlife species had an overall molecular percentage positivity of 30.16%; however, considering individual animal species that were sampled, the Waterbucks had the highest positivity rate, that is, 54.54%. All the samples were confirmed as genus Cryptosporidium with less species discrimination as our PCR target was a short fragment. There is a need to investigate the risk factors that predispose to high Cryptosporidium infection in the study area, especially in Kasenyi. In-depth investigation of the genetic diversity of Cryptosporidium spp. circulating at the human, livestock, and wildlife interface is imperative in devising disease management strategies. Full article

The common gull (Larus canus) and the black-headed gull (Larus ridibundus) are common waterbird species in Lithuania. Until now, the composition of Sarcocystis species in these birds was unknown. The current study aimed to identify Sarcocystis spp. by the morphological examination of sarcocysts found in the muscle tissues and by DNA sequence analysis. Between 2011 and 2019, the leg muscles of 42 common gulls and 63 black-headed gulls were tested for Sarcocystis spp. Based on the methylene blue staining of squashed muscle samples, sarcocysts were detected in six common gulls (14.3%) and in six black-headed gulls (9.5%). Under a light microscope, one type of microcyst was observed. Sarcocysts were thread-like (2860–8250 × 40–180 μm) and had a smooth and thin (0.8–1.4 μm) cyst wall, while bradyzoites were banana-shaped and 5.0–9.2 × 1.3–2.4 μm in size. The sequencing of complete ITS1 showed the presence of S. columbae, S. halieti and S. wobeseri in the common gull and S. columbae and S. halieti in the black-headed gull. The highest intraspecific genetic variability was established for S. halieti, which is characterized by a wide host range. This species is considered to be pathogenic, therefore further histopathological examination of the various organs of gulls is needed. Full article

Eosinophilia is common in low-resource countries and usually implies helminthiasis. Since helminthiasis is a common cause of eosinophilia and its diagnosis is cumbersome, we hypothesized that broad-spectrum anthelmintic therapy may decrease the eosinophil count and eventually cure helminthiasis, whether microbiologic diagnosis is established or not. We recruited patients with eosinophilia aged 5 years and older who presented to Dhulikhel hospital, Nepal. Patients were treated with albendazole and ivermectin. A stool sample for microscopy was obtained. Of a total of 113 patients, 106 had a follow-up visit and 56 were classified as responders to treatment (defined as a decrease in eosinophil count to below 500 cells/µL, or an absolute decrease of more than 1000 cells/µL). For all patients, we found an absolute decrease in the eosinophil count and for the responding group (more than 50% of the whole cohort), the eosinophil count decreased substantially. All stool samples were negative. The reason for a lack of response in the remaining patients is unclear. In order to ascertain whether eosinophilia should be an indication for anthelmintic treatment, a randomized controlled study of empirical treatment after a thorough microbiologic workup is needed. Full article

(1) Intestinal microbial parasites are major contributors to the global burden of gastrointestinal disease. Such infections are mainly caused by Cryptosporidium, Giardia duodenalis, and Entamoeba histolytica. These parasites are transmitted either directly or indirectly through oral–fecal routes. Previous reports suggested that camels could play a role in the zoonotic transmission of various clinically and veterinary important intestinal parasites, however, limited data are available on intestinal infections of camels, particularly on a molecular level. We aimed to explore the occurrence of these three parasites in camels (Camelus dromedarius) in Algeria. (2) A total of 68 samples—63 stool samples from camels and five from the environment—were collected from two desert regions in Algeria and analyzed using PCR and qPCR methods. (3) Overall, 7% of the camels tested positive for zoonotic subtypes of Cryptosporidium spp., while 16% of the camels tested positive for G. duodenalis. Two environmental samples also tested positive for G. duodenalis. None of the samples were positive for Entamoeba histolytica. (4) Our results provide one of the first molecular-based identification of these gut parasites in dromedary camels in Algeria. The presence of G. duodenalis in the host and the environment unveils, in part, the circulation route of this parasite. Our results will spearhead further investigations into the prevalence and epidemiology of gut parasites in hoofed animals and raise questions concerning their role in health and disease in the area. Full article

Toxoplasmosis in immunocompromised patients results in either reactivation of latent toxoplasmosis or acute infection. In the framework of the kidney transplantation program in Senegal, the serological screening of potential pre-transplant and transplanted patients can prevent the disease. This study aimed to assess the seroprevalence of toxoplasmosis in a cohort of hemodialysis patients, candidates for kidney transplantation. To this end, a multicentre cross-sectional study was conducted in 2020 in six dialysis units from five regions. Blood samples and sociodemographic data were collected from each patient. IgG and IgM against T. gondii antibodies were assessed by a chemiluminescent method using Architect ci4100, and statistical analysis was performed using R software. Overall, 211 hemodialysis patients aged from 18 to 77 years were enrolled. The mean age was 42.62 years ± 13.6, and the sex ratio M/F was 1.24. The overall seroprevalence of T. gondii was 41.7%, with the highest value being recorded in the region of Kaolack (44.4%). Patients aged over 60 years were more typically infected, at a proportion of 56.0%. Regarding sex, males elicited a higher prevalence (44.4.%) than females did. Patients of an upper socioeconomic status were less affected, and contact with cats was not associated with toxoplasmosis. By education level, the illiterate group was most affected one. Overall, this first study of toxoplasmosis among Senegalese hemodialysis patients indicates high seroprevalence. Full article

Many new marine parasite species are added every year. Still, in some places, mainly tropical regions, marine parasites have been little studied. An exhaustive review of the indexed publications where species of parasites are reported in the marine environments of Costa Rica was carried out. The history of research on marine parasites in this region is also reviewed. A total of 147 species of marine parasites have been reported in Costa Rica as parasites of 61 different species of hosts. Most of these parasites correspond to trematodes and cestodes, found mainly in the digestive tract of their vertebrate hosts. In Costa Rica, marine parasites have been studied mainly in sea turtles, elasmobranchs, fish, and dolphins. Most marine parasites have been reported based on morphological identifications of adult stages, and most of the work done so far consists of taxonomic identifications (species reports), with little contribution to the pathology and other aspects of the parasites–hosts interactions. The technical difficulties for research in marine parasitology, the lack of sampling in certain groups of hosts, and the lack of a consolidated research group in marine wildlife parasitology in Costa Rica are factors that have prevented a greater and faster advance in the knowledge of the biodiversity of marine parasites in this country. Full article

Considering that health professionals at Brazil had doubts about the entomoepidemiological issues of Chagas disease (CD), and that many of them highlighted not feeling totally safe for clinical care, the knowledge of 281 Brazilian medical students was evaluated through a cross-sectional, descriptive, prospective, and quantitative research. Most students demonstrated that they knew about the etiological agent of CD (Trypanosoma cruzi), since 279 students answered the questionnaire correctly. Furthermore, the medical students demonstrated knowledge of the main form of transmission of the parasite, as 278 students associated CD transmission with triatomines. On the other hand, approximately 25 students did not associate CD transmission with triatomine feces. Besides that, these future health professionals had difficulties in relation to the treatment of CD, as more than half of the students (176) wrongly answered that CD “is not curable” or “is curable in the chronic phase”. Based on the results obtained that point out the difficulties medical students have with CD, there is a need for undergraduate medical courses to address the neglected diseases holistically because the National Curriculum Guidelines for the medical course require the training of competent health professionals capable of integrating the biological, psychological, social, and environmental dimensions. Full article

This study assessed the efficiency of a new in vitro tick feeding system for the adult Rhipicephalus appendiculatus tick and compared the impact of different blood anticoagulating factors on their feeding process. A total of 10 feeders were each seeded with 30 or 60 R. appendiculatus adults. Bovine blood was added into each unit and changed every 12 h for 4 to 10 days during which tick attachment and engorgement was assessed. The tick attachment observed 4 days after feeding was 80.0% (48/60), 75.8% (182/240), and 70.8% (170/240) for lithium heparin, citrate phosphate dextrose, and defibrinated blood, respectively, with no significant difference (p > 0.05) between the anticoagulants used. However, the ticks fed on heparinized and defibrinated blood reached repletion status. The in vitro tick feeding system was successfully used to feed adult R. appendiculatus ticks until repletion. This system could be used to facilitate studies on tick-pathogen interactions, such as those involved in the East Coast fever disease. Full article