Parasite最新文献

Schistosomiasis is an endemic disease in Côte d'Ivoire. We compared the conventional Kato Katz (KK) test and a more sensitive but rarely used method, the point-of-care circulating cathodic antigen (POC-CCA), in order to contribute to the development of a more appropriate strategy for the control and elimination of intestinal schistosomiasis in western Côte d'Ivoire. A cross-sectional epidemiological survey was conducted in eight elementary schools in the Guémon and Cavally regions from February to December 2020. Selected schoolchildren provided stool and urine samples to detect the presence of Schistosoma mansoni eggs and parasite antigen using the KK and POC-CCA tests, respectively. A total of 554 schoolchildren were included in the study. The overall prevalence of intestinal schistosomiasis was 10% and 67% for KK and POC-CCA, respectively. The POC-CCA detected an infection rate of 100%, while the KK yielded a rate of 42%. In schools, prevalence ranged from 27 to 100% with POC-CCA and from 0 to 42% with KK. Swimming, fishing, washing clothes, and dishwashing were significantly associated with the onset of infection and high intensities. The epidemiological risk factors for intestinal schistosomiasis updated here using KK and POC-CCA diagnostic methods showed that prevalence was much higher than previously estimated using the KK. The POC-CCA is more sensitive and ways should be considered to improve its specificity in order to improve the diagnosis.

Feline pulmonary capillariosis is a significant disorder due to its distribution and clinical impact. This study evaluated the safety and efficacy of two administrations 28 days apart of a topical solution containing esafoxolaner, eprinomectin and praziquantel (NexGard^® Combo) in treating Eucoleus aerophilus (syn. Capillaria aerophila) infection in naturally infected cats. Cats were allocated to two groups: G1 cats (n = 23) received two treatments at study days (SDs) 0 and 28 (±2) and were evaluated for 6 weeks, and G2 cats (n = 17) served as a negative control for 6 weeks and were then treated twice on SDs 42 (±2) and 70 (±2), allowing for an additional 6-week assessment of efficacy. Each cat was subjected to McMaster coproscopy at SDs -7/0, 28 (±2) and 42 (±2) for both groups, 70 (±2) and 84 (±2) only for G2. Clinical examination and chest radiographic images were performed at SDs 0, 28 (±2) and 42 (±2) for G1 and G2, 70 (±2) and 84 (±2) only for G2. The comparison of EPG (eggs per gram of feces), clinical (CS), and radiographic scores (RS) at each time-point was used as a criterion. The efficacy based on the EPG reduction was 99.5% (G1) and 100% (G2) after two administrations of NexGard^® Combo 2 weeks apart. At SD 0, no significant differences for CS and RS were recorded between G1 and G2, while a significant reduction (p < 0.05) was observed post-treatment for CS, RS, oculo-nasal discharge, auscultation noises, and cough. Two doses of NexGard^® Combo 28 days apart stopped egg shedding and significantly improved clinical alterations in cats infected by E. aerophilus.

Anisakid nematodes are a globally distributed group of marine mammal parasites. Kogiid whales, including the pygmy sperm whale Kogia breviceps, host an assemblage of specific anisakid species. Currently, three species are known to be specific to kogiid hosts, i.e., Skrjabinisakis paggiae, S. brevispiculata, and the less studied Pseudoterranova ceticola. The aim of this study was to investigate the species diversity of anisakid nematodes sampled from a pygmy sperm whale stranded in 2013 at the edge of its distribution range in the Northeast Atlantic, specifically in the North of Scotland. Nematodes were assigned to genus level based on morphology and identified by sequence analysis of the mtDNA cox2 gene and the rDNA ITS region. The present finding represents the first observation of syntopic occurrence of adult stages of S. brevispiculata, S. paggiae, and P. ceticola in a pygmy sperm whale in the Northeast Atlantic, and represent the northernmost record of these species in this area. Skrjabinisakis brevispiculata was the most abundant species, accounting for 55% of the identified nematodes, predominantly in the adult stage. Anisakis simplex (s.s.) was also abundant, with most specimens in the preadult stage, followed by S. paggiae and P. ceticola. The pygmy sperm whale is rarely documented in Scottish waters, and its occurrence in the area could suggest expansion of its geographic range. The presence of S. brevispiculata, S. paggiae, and P. ceticola in this whale species in this region may indicate a shift in the whole host community involved in the life cycle of these parasites in northern waters. However, it is also plausible that these parasites were acquired while the whale was feeding in more southern regions, before migrating northbound.

Eimeria tenella is an obligate intracellular parasite which causes great harm to the poultry breeding industry. Protein phosphorylation plays a vital role in host cell-E. tenella interactions. However, no comprehensive phosphoproteomic analyses of host cells at various phases of E. tenella infection have been published. In this study, quantitative phosphoproteomic analysis of chicken embryo DF-1 fibroblasts that were uninfected (UI) or infected with E. tenella for 6 h (PI6, the early invasion phase) or 36 h (PI36, the trophozoite development phase) was conducted. A total of 10,122 phosphopeptides matched to 3,398 host cell phosphoproteins were identified and 13,437 phosphorylation sites were identified. Of these, 491, 1,253, and 275 differentially expressed phosphorylated proteins were identified in the PI6/UI, PI36/UI, and PI36/PI6 comparisons, respectively. KEGG pathway enrichment analysis showed that E. tenella modulated host cell processes through phosphorylation, including focal adhesion, regulation of the actin cytoskeleton, and FoxO signaling to support its early invasion phase, and modulating adherens junctions and the ErbB signaling pathway to favor its trophozoite development. These results enrich the data on the interaction between E. tenella and host cells and facilitate a better understanding of the molecular mechanisms underlying host-parasite relationships.

The plerocercoid larvae of Spirometra mansoni are etiological agents of human and animal sparganosis. Annexins are proteins with important roles in parasites. However, our knowledge of annexins in S. mansoni is still inadequate. In this study, 18 new members of the Annexin (ANX) family were characterized in S. mansoni. The clustering analysis demonstrated that all the SmANXs were divided into two main classes, consistent with the patterns of conserved motif organization. The 18 SmANXs were detected at all developmental stages (plerocercoid, adult, and egg) and displayed ubiquitous but highly variable expression patterns in all tissues/organs studied. The representative member rSmANX18 was successfully cloned and expressed. The protein was immunolocalized in the tegument and parenchyma of the plerocercoid and in the tegument, parenchyma, uterus and egg shell of adult worms. The recombinant protein can bind phospholipids with high affinity in a Ca²⁺-dependent manner, shows high anticoagulant activity and combines with FITC to recognize apoptotic cells. Annexin gene polymorphism and conservative core motif permutation were found in both cestodes and trematodes. SmANXs also revealed high genetic diversity among Platyhelminthes of medical interest. Our findings lay a foundation for further studies on the biological functions of ANXs in S. mansoni as well as other taxa in which ANXs occur.

Wild rodents serve as reservoirs for Cryptosporidium and are overpopulated globally. However, genetic data regarding Cryptosporidium in these animals from China are limited. Here, we have determined the prevalence and genetic characteristics of Cryptosporidium among 370 wild rodents captured from three distinct locations in the southern region of Zhejiang Province, China. Fresh feces were collected from the rectum of each rodent, and DNA was extracted from them. The rodent species was identified by PCR amplifying the vertebrate cytochrome b gene. Cryptosporidium was detected by PCR amplification and amplicon sequencing the small subunit of ribosomal RNA gene. Positive samples of C. viatorum and C. parvum were further subtyped by analyzing the 60-kDa glycoprotein gene. A positive Cryptosporidium result was found in 7% (26/370) of samples, involving five rodent species: Apodemus agrarius (36), Niviventer niviventer (75), Rattus losea (18), R. norvegicus (155), and R. tanezumi (86). Their respective Cryptosporidium positive rates were 8.3%, 5.3%, 11.1%, 7.1%, and 7.0%. Sequence analysis confirmed the presence of three Cryptosporidium species: C. parvum (4), C. viatorum (1), and C. muris (1), and two genotypes: Cryptosporidium rat genotype IV (16) and C. mortiferum-like (4). Additionally, two subtypes of C. parvum (IIdA15G1 and IIpA19) and one subtype of C. viatorum (XVdA3) were detected. These results demonstrate that various wild rodent species in Zhejiang were concurrently infected with rodent-adapted and zoonotic species/genotypes of Cryptosporidium, indicating that these rodents can play a role in maintaining and dispersing this parasite into the environment and other hosts, including humans.

Snakes are sometimes regarded as pets and are used in traditional Chinese medicine. Cryptosporidium spp. are frequently identified in snakes, representing an important pathogen and causing gastrointestinal diseases. Current data indicate that risk factors for infection and patterns of clinical symptom presentation may differ among Cryptosporidium spp. To better understand the infection status by Cryptosporidium spp., fecal samples were collected from 603 asymptomatic and 147 symptomatic snakes in 26 provinces of China. These samples came from Elaphe guttata, Elaphe obsoleta, Pituophis melanoleucus, Thamnophis sirtalis, Lampropeltis getulus, and Heterodon nasicus. The partial small subunit (SSU) rRNA gene was amplified using nested polymerase chain reaction (PCR) to investigate the infection rate of Cryptosporidium spp., and to assess evolutionary relationships and genetic characterization. A prevalence of 20% was recorded in asymptomatic snakes, with age identified as a significant risk factor. In contrast, 70% of symptomatic snakes were positive for Cryptosporidium spp., with Cryptosporidium serpentis and Cryptosporidium varanii (syn. C. saurophilum). Further analysis revealed a potential association between C. serpentis and regurgitation, and C. varanii and diarrhea, while neither species was linked to flatulence. To our knowledge, this is the first study to report Cryptosporidium spp. and associated clinical signs in symptomatic snakes in China. This study aims to enhance the understanding of Cryptosporidium infections, risk factors, and clinical manifestations in snakes, providing data crucial for the control and prevention of cryptosporidiosis.

Hyalomma anatolicum and Rhipicephalus microplus are tick species that are important vectors of numerous pathogens affecting both humans and livestock. Endosymbionts, such as Coxiella-like endosymbionts (CLE), Francisella-like endosymbionts (FLE), and Candidatus Midichloria, play a crucial role in the physiology and vector competence of these ticks. In this study, we investigated the microbial composition of H. anatolicum and R. microplus from four geographically distinct regions of Pakistan to assess whether environmental differences influence their microbiomes. We analyzed the ticks' gut microbiome targeting the V3-V4 hypervariable region of 16S rRNA for Illumina 16S metagenome NGS sequencing and processed overall 144 ticks. Analysis of gut bacterial composition resulted in observation of 1200 R. microplus and 968 H. anatolicum unique amplicon sequencing variants (ASVs). Relative abundance, Alpha diversity (Shannon, Faith's phylogenetic distance) and beta diversity metrics (Bray-Curtis, Jaccard and UniFrac) were analyzed and revealed that H. anatolicum ticks have significantly unique and diverse microbial communities with Acinetobacter indicus and Francisella-like endosymbionts dominating as opposed to Candidatus Midichloria. Rhipicephalus microplus exhibited results consistent with the previous studies with no major changes in microbiome including Coxiella-like endosymbionts as the major contributor. These findings suggest that geographical and environmental factors play a significant role in shaping the tick microbiome, with potential consequences for disease transmission and tick survivability. Further research is needed to elucidate the functional roles of these microbial shifts and their impact on public health and livestock in affected regions.

Enterocytozoon bieneusi, a zoonotic pathogen prevalent in both humans and animals, is the most frequently diagnosed microsporidian species in humans and presents significant public health risks. However, data on the prevalence and genotypes of E. bieneusi in farmed minks (Neovison vison) and raccoon dogs (Nyctereutes procyonoides) in China are limited. Therefore, 275 minks (89 from Hebei Province, 57 from Heilongjiang Province, 109 from Liaoning Province, 20 from Shandong Province) and 235 raccoon dogs (114 from Hebei Province, 27 from Heilongjiang Province, 61 from Liaoning Province, 33 from Jilin Province) were examined for the prevalence and genotypes of E. bieneusi through sequence analysis of the internal transcribed spacer (ITS) region of the rRNA gene. The overall prevalence of E. bieneusi was 18.6% (95/510), with 10.5% (29/275) in farmed minks and 28.1% (66/235) in raccoon dogs. Ten genotypes (CHN-F1, genotype D, Type IV, EbpC, NCF2, NCF5, NCF6, Peru8, Henan V, and MJ5) were identified in minks and raccoon dogs. This study is the first to detect the CHN-F1, NCF2, NCF6, Peru8, and Henan V genotypes in minks and the NCF5, NCF6, and MJ5 genotypes in raccoon dogs. Additionally, the D, Type IV, and Peru8 genotypes, previously identified in humans, were also found in minks and raccoon dogs, suggesting that these animals could be potential sources of human microsporidiosis. These findings expand the understanding of E. bieneusi's host distribution in China and contribute to the prevention of zoonotic E. bieneusi infections among farmed animals.

Tick-borne Apicomplexa encompass a group of parasites responsible for significant medical and veterinary diseases, including babesiosis, theileriosis, and hepatozoonosis. In this study, we investigated the presence and diversity of tick-borne Apicomplexa in wildlife and ticks inhabiting the Amazon rainforests of French Guiana. To this end, we conducted molecular screening and typing using 18S rRNA sequences on a collection of 1161 specimens belonging to 71 species, including 44 species of wild mammals, five species of passerines, and 22 species of ticks. We characterized eight genovariants of Babesia, Theileria, Hemolivia, and Hepatozoon parasites, some matching known species, while others suggested potential novel species. These parasites were detected in wild mammals, including opossums, sloths, armadillos, porcupines, margays, greater grisons, and ticks, but not in passerines. Finally, similarities with surveys conducted in Brazil highlight the specific sylvatic transmission cycles of South American tick-borne Apicomplexa.