Parasitology Research最新文献

Treatment failure with amodiaquine was reported in Dangassa, where red blood cell (RBC) polymorphisms are found and seasonal malaria chemoprevention (SMC) is underway. Here, we aimed at assessing the influence of RBC polymorphisms on SMC effectiveness. This was a secondary analysis of data from a study conducted in Dangassa. Children aged 5 to 14 years enrolled in an open randomized study were assigned either to receive SMC (intervention arm) or not (control arm). SMC was implemented from July to November. For all children, hemoglobin type and blood group were determined at enrolment in July, and parasitemia and hemoglobin level were monthly monitored by finger-prick. Overall, 166 children were enrolled among which 82 (49.40%) in the control arm and 84 (50.60%) in the SMC arm. The prevalence of HbAS was 10.24% (17/166) with 12.20% in the control and 8.33% in the SMC arm. O group was the most common overall (45%) and in the SMC arm (54%), but the control arm had more B (39.02%) than O (36.59%). In the SMC arm, no case of Plasmodium infection and malaria disease was observed in the 7 HbAS children while in Non-HbAS children, peaks of infection and disease prevalence were respectively observed in October (24.66%) and November (7.14%). For the SMC arm, in group O and Non-group O, Plasmodium infection cases were observed from August to December. Plasmodium infection and malaria disease were more frequently observed in HbAS children in the control arm than in the SMC arm. Further studies are needed to assess factors associated with the asymptomatic carriage of parasites during SMC in Dangassa. NCT04149106.

Blood parasites from the order Haemosporida infect many vertebrates and cause malaria-like diseases. In this study, a haemosporidian infection was detected in a sick grey crowned crane imported into China using a combination of morphological and molecular approaches. Blood samples were collected from the jugular vein and processed for morphological identification of infective parasites using stained blood smears and microscopy. No merogony occurs in the blood cells, and sporadic pigment granules were observed. Nested-PCR assays were employed for a molecular examination, which indicated that the cytb gene of this parasite had 94.1-94.9% identity to Haemoproteus antigonis. Subsequently, its mitochondrial genome structure was determined by high-throughput sequencing using the DNBSEQ-T7 platform. The determined structure was confirmed by the Sanger sequencing using amplicons. The mitochondrial genome obtained for this parasite exhibited a low CG content (32.0%) and possessed three protein-coding genes, encoding 1068 amino acids, which constituted 53.7% of the genome. Phylogenetic analysis indicated that this parasite clustered with Haemoproteus sp. is detected in grey crowned cranes from Africa. This parasite was likely acquired during importation of this animal; thus, strict quarantine of imported ornamental animals is required to prevent the entry of new pathogens.

The European badger (Meles meles) is a common mustelid species known as a significant reservoir for various human and animal diseases. Studies investigating Leishmania infection in European badgers across Mediterranean regions have yielded inconsistent findings. In Spain, results are particularly controversial: some studies confirm the presence of Leishmania in badgers, while others do not. Our study aimed to conduct a retrospective histopathological and immunohistochemical analysis to detect Leishmania in tissues of nine European badgers from northeastern Spain, a region previously unevaluated for Leishmania infection in this species. Microscopic examination revealed lesions indicative of leishmaniosis in the lymph nodes and spleens of six badgers. In one of them, Leishmania-like structures were identified in multiple organs and confirmed via immunohistochemistry. Parasites were detected in the lymph nodes, spleen, adrenal glands, and pancreas. The parasite load was high in the adrenal glands, moderate in the lymph nodes and spleen, and low in the pancreas. No parasites were found in other examined organs. This finding represents a frequency of 11.11% (1/9) of Leishmania infection among the badgers we studied. Further investigation of wildlife and atypical reservoirs can enhance our understanding of the pathogenesis of this significant zoonotic disease.

In this study conducted along the coast of Odisha, India, reproductive trade-offs in isopods of the family Cymothoidae were investigated, focusing on the relationship between the number vs. volume of eggs and the percentage of brood to body volume. Ovigerous females from species with substantial sample sizes (n > 30) were analyzed to understand their survival strategies. The findings highlight distinct strategies among different parasite types within Cymothoidae. Buccal parasites such as Cymothoa frontalis and Cymothoa indica, along with branchial parasites like Joryma sawayah and Agarna malayi, generally produced a higher number of smaller eggs, except for A. malayi, which produced fewer but larger eggs. In contrast, the external body surface-attaching parasite, Nerocila orbignyi, was observed to produce fewer eggs of larger size. Across all parasite types (intraspecific), there was a statistically significant negative correlation between egg number and egg volume (p < 0.05). Buccal parasites were observed to have the highest percentage of marsupium volume relative to body volume, indicating a strategy to maximize egg storage. Conversely, external body surface-attaching parasites had the lowest percentage, possibly reflecting adaptation to a different reproductive environment. Additional observations revealed anatomical adaptations in all the studied isopod species which include the shift of the alimentary canal to the dorsal side to accommodate the development of the marsupial sac for egg incubation. In summary, these findings illustrate how parasitic isopods of the family Cymothoidae manage trade-offs between reproductive potential and success, crucial for their species' continuity and survival strategies in coastal ecosystems.

Chicken coccidiosis, caused by Eimeria spp., seriously affects the development of the poultry breeding industry. Currently, extensive studies of chicken coccidiosis are mostly focused on acquired immune responses, while information about the innate immune response of chicken coccidiosis is lacking. Toll-like receptor (TLR), the key molecule of the innate immune response, connects innate and adaptive immune responses and induces an immune response against various pathogen infections. Therefore, the quantitative real-time PCR was used to characterize the expression profile of chicken TLRs (chTLRs) and associated cytokines in the cecal tonsil of chickens infected with Eimeria tenella. The results showed that the expression of chTLR1a, chTLR2a, and chTLR5 was significantly upregulated at 3 h post-infection, while chTLR1b, chTLR2b, chTLR3, chTLR7, chTLR15 and chTLR21 was significantly downregulated (p < 0.05). In addition, chTLR1a expression rapidly reached the peaked expression at 3 h post-infection, while chTLR2b and chTLR15 peaked at 168 h post-infection, and chTLR2a expression was highest among chTLRs, peaking at 48 h post-infection (p < 0.05). For cytokines, interleukin (IL)-6 and tumor necrosis factor (TNF)-α peaked at 96 h post-infection, IL-4 and IL-12 peaked at 144 h post-infection, and interferon-γ expression was highest among cytokines at 120 h post-infection. In addition, IL-12 and IL-17 were markedly upregulated at 6 h post-infection (p < 0.05). These results provide insight into innate immune molecules during E. tenella infection in chickens and suggest that innate immune responses may mediate resistance to chicken coccidiosis.

Canine dirofilariosis is a mosquito-borne zoonotic disease largely caused by Dirofilaria immitis. Mainly present in temperate, semitropical, and tropical areas, its worldwide emergence and spread are causing concern. In Argentina, most cases have been reported in humid regions of the center and northeast of the country. The occurrence of canine dirofilariosis in an arid environment of western Argentina was investigated by blood smears, microhematocrit tube test, and Knott's technique. Association and odds ratio were determined in relation to dog characteristics. Thirty-three dogs (51.6%) had microfilariae, morphologically identified as D. immitis. Knott's test was more sensitive in detecting the positive animals. The odds of harboring microfilariae were 12, 29, and 66 if the dog was male, adult (three to 6 years old), or older (> 7 years old), respectively. The prevalence of canine dirofilariosis herein reported outstands among the highest in Argentina and extends to the west its geographic distribution in the country. Far from being an exception, this epidemiological situation might reflect similar circumstances in several arid locations in the west and center of Argentina. Being this a disease of recent appearance in the region, both veterinarians and physicians should be aware of its potential to cause disease in animals and humans.

Metastrongyloid nematodes typically reside as adults in the cardiopulmonary systems of their mammalian definitive hosts, potentially causing severe diseases. Of particular concern are Angiostrongylus cantonensis and A. costaricensis, which can cause eosinophilic meningitis and abdominal angiostrongyliasis, respectively, in their accidental human hosts. Several metastrongyloid species of medical and veterinary importance have been documented in the Canary Islands. However, the gastropod species acting as intermediate hosts for some of these nematodes in the archipelago remained unknown. This study aimed to investigate the occurrence of metastrongyloid nematodes in terrestrial and aquatic gastropods, including both endemic and non-native species, on Tenerife. Foot samples from terrestrial and aquatic gastropods were analyzed using a multiplex PCR targeting the Internal Transcribed Spacer 1 (ITS1), allowing the specific detection of A. cantonensis, A. vasorum, Aelurostrongylus abstrusus, Crenosoma striatum, Troglostrongylus brevior, and Crenosoma vulpis. Five metastrongyloid species, namely C. striatum, A. cantonensis, Ae. abstrusus, A. vasorum, and an unidentified metastrongyloid, were identified within both non-native and endemic terrestrial gastropods. In the aquatic snail Physella acuta, only A. cantonensis and C. striatum were detected. This study confirms the introduction of various metastrongyloids associated with non-native mammalian fauna and provides new data on the occurrence of these nematodes in non-native and endemic gastropod species, including their presence in aquatic environments on the Canary Islands.

The increasing spread of mosquito vectors has made mosquito-borne arboviral diseases a global threat to public health, leading to the urgent need for effective population control methods. Strategies based in the intracellular bacterium Wolbachia Hertig, 1936 are considered environmentally friendly, safe for humans, and potentially cost-effective for controlling arboviral diseases. To minimize undesirable side effects, it is relevant to assess whether Wolbachia is present in the area and understand the diversity associated with native infections before implementing these strategies. With this purpose, we investigated Wolbachia infection status, diversity, and prevalence in populations of Aedes albifasciatus (Macquart, 1838), Aedes fluviatilis (Lutz, 1904), and hybrids of the Culex pipiens (Linnaeus, 1758) complex from Argentina. Aedes albifasciatus and C. pipiens complex samples were collected in the province of Buenos Aires, and A. fluviatilis in the province of Misiones. Aedes albifasciatus was found to be uninfected, while infections with strains wFlu and wPip were detected in A. fluviatilis and hybrids of the C. pipiens complex, respectively. All strains were fixed or close to fixation and clustered within supergroup B. These finding provides valuable information on Wolbachia strains found in natural mosquito populations in Argentina that might be used in heterologous infections in the future or be considered when designing control strategies based on Wolbachia infection.

Among different climatic zones in India, the tropical monsoon region comprises a diverse ecosystem characterized by the endemic nature of several parasites including certain emerging and re-emerging vector-borne pathogens of humans, whereas a systematic investigation of the occurrence of different parasites among domestic goats in this area is not yet explored. The goal of the present study is to explore the parasite diversity focusing on molecular identification of vector-borne hemoparasites and its health impacts on domestic goats reared in the tropical monsoon climate zone of Kerala, India. Among 227 goats presented to the Teaching Veterinary Clinical Complex (TVCC) in the monsoon months of 2023, thirty animals were recruited for the study. The animals were screened for the presence of different hemoparasites (Anaplasma spp., Theileria spp., and Babesia spp.), ectoparasites (ticks, lice, and fleas), and gastrointestinal (GI) parasites (hookworms, threadworms, tapeworms, whipworms, and coccidia). The isolated hemoparasites were further characterized by sequencing and phylogenetic analysis. The correlation studies to elucidate the association between the occurrence of different parasites and clinical manifestations (hyperthermia, pallor of mucous membrane, circulatory failure, respiratory signs, neurological instability, and GI signs), blood picture (anemia, leukopenia, thrombocytopenia), demographics (sex and age), and treatment history (hemoparasitic therapy, ectoparasiticidal application, and prophylactic deworming) were conducted. The co-infection status of these parasites was also evaluated. A substantial portion of the goats in the study group was found to be affected by vector-borne hemoparasitic diseases and their arthropod vectors or GI parasites or both. This can be attributed to the constantly warm and humid climate of the region, which is favorable for the survival and growth of different life cycle stages of these parasites and vectors. A strategic parasitic disease surveillance-cum-control program is the need of the hour for ensuring climate resilience and profitable goat farming in the region.

According to WHO, between 2000 and 2021, there were approximately 247 million malaria cases and 627,000 deaths globally, with the majority of cases occurring in sub-Saharan Africa. In Turkey, indigenous P. vivax malaria was a major public health problem until its eradication was achieved in 2010. Although indigenous malaria transmission has been significantly reduced since 2010, the country is challenged with imported malaria due to increasing global travel and migration from endemic regions. In this study, all imported malaria cases admitted to Dr. Sadi Konuk Research and Training Hospital, Istanbul, between 2018 and 2023 were included. DNA extraction was performed using archived slides and EDTA blood samples. Real-time PCR was performed to identify samples at the species level using previously reported primers and probes. In addition, all available patient demographics are presented. During the six years between 2018 and 2023, 157 patients were diagnosed with imported malaria. According to the real-time PCR results, 149 cases were P. falciparum (94.9%), five cases were P. vivax (3.2%), two cases were P. ovale (1.3%), and one case was P. malariae (0.6%). The male/female ratio among diagnosed patients was 2.34 (110♂/47♀) among diagnosed patients. Plasmodium falciparum was detected in patients from all African regions, whereas P. vivax was detected only in patients from Liberia and Djibouti. Although malaria cases in Turkey have significantly decreased due to elimination efforts and effective public health interventions, the recent increase in both imported and indigenous cases, as well as the presence of suitable vector species in the country, indicates that malaria still remains a serious public health problem for Turkey.