Parasitology Research最新文献

This field study evaluated the effectiveness and safety of a single dose of a combination of milbemycin oxime and lotilaner (Credelio^® Plus) against Toxocara canis, Trichuris vulpis, and Ancylostoma caninum in dogs under field conditions in Korea. This clinical study was conducted with client-owned dogs under field conditions from April 2023 to May 2024. The drug was administered on Day 0, and fecal samples were collected on Days - 7, 0, 7, and 14. Samples were analyzed using fecal flotation for qualitative assessment and the modified McMaster method for quantitative determination of egg counts. A total of 25 dogs from 25 different households were enrolled. The geometric mean reduction rates for all target nematode species and total infections were 100%. No adverse events or significant changes in body weight, physical examination findings, or hematology and serum chemistry parameters were observed. The results of this study support the effectiveness and safety of the drug against gastrointestinal nematodes in dogs under field conditions in Korea. These results indicate that this combination product may serve as a valuable tool in veterinary parasite control, ultimately contributing to improved canine health.

The latest taxonomy recognizes two Spirometra species in Asia: S. mansoni and S. asiana, with the former exhibiting a global distribution. The isolates analyzed in this study were classified accordingly, and a S. mansoni isolate from India was identified using morphology, Polymerase Chain Reaction (PCR), sequencing, and phylogenetics. Furthermore, a global analysis of genetic diversity, haplotype network structure, and population dynamics of Spirometra spp. was conducted using the 28S rRNA marker. Phylogenetic analysis of Spirometra sequences (n = 104) revealed two distinct clades: a larger clade with Asian (China, Korea, and India) and African (Egypt) sequences (reclassified as S. mansoni) and a smaller clade with European (Latvia and Finland) sequences (true S. erinaceieuropaei). The Asian S. mansoni population showed high haplotype diversity (Hd = 0.821 ± 0.035) and moderate nucleotide diversity (π = 0.00695 ± 0.00054). Asian haplotypes were closely related, with Hap_6 being the most common. The European S. erinaceieuropaei population formed a single haplotype (Hap_15) and exhibited no genetic variation. Population dynamics suggested expansion in global and Asian populations, with strong geographic structuring. The global mismatch distribution indicated a structured population with variable genetic diversity among populations. Genetic differentiation between continents was evident and AMOVA results confirmed that most genetic variation was due to differences among continental populations. This study confirmed S. mansoni in India, clarified its global spread, and provided insights into its population dynamics. The results can inform public health strategies, improve understanding of these zoonotic tapeworms, and help reduce transmission risks to humans.

Hyalomma marginatum is a hard tick vector of various pathogens, including Crimean-Congo Haemorrhagic fever. This species has a wide distribution, from North Africa to Eastern Europe. Despite previous regional studies ofHyalomma marginatum, no research has yet focused on its intra-island genetic diversity and population dynamics. This study aims to investigate the introduction zones, genetic variability, and population structure of Hyalomma marginatum in Corsica thereby, enhancing our understanding of how its populations are distributed and maintained across the island. Ticks were collected from cattle and horses across Corsica between 2022 and 2024, and their morphological identification was conducted. DNA was extracted and two mitochondrial genes (12S and COX1) were amplified and sequenced with the Sanger method. Genetic diversity, phylogenetic relationships, and population structure were analyzed. A total of 162Hyalomma marginatum ticks were collected from cattle and horses from 2022 to 2024 and grouped into 133 pools. Genetic analyses focused on the COX1 gene and concatenated COX1 and 12S sequences revealed high haplotype diversity, with 21 COX1 haplotypes and 16 concatenated haplotypes identified, particularly in central and southern Corsica. One dominant COX1 haplotype was widely distributed across the island. AMOVA indicated that most genetic variation occurred within populations (FST = 0.225 for COX1; FST = 0.158 for concatenated sequences; p < 0.01). Corsican haplotypes were closely related to other Eurasian sequences, particularly Croatia, but more divergent from Asian ones like China. This study reveals significant genetic diversity in Hyalomma marginatum across Corsica, with patterns shaped by geography and host movement. The COX1 gene proved to be a considerably more informative genetic marker than 12S, providing higher resolution for haplotype differentiation and phylogenetic analysis. Results suggest a recent population expansion, limited gene flow, and possible roles of livestock in tick dispersal.

The increasing resistance to chemical pediculicides has raised concerns about the efficacy of head lice treatments, including in Thailand. This study evaluated the efficacy of three commercially available pediculicide shampoos (0.75% permethrin, 0.6% carbaryl, and 0.12% Stemona root crude extract) among infested children in Chonburi Province, Thailand. A pre-test/post-test experimental design was conducted with 135 infested female children assigned to three treatment groups (n = 45 each), with no significant differences in baseline demographic characteristics (level of head lice infestations, hairstyle, and hair length). Each group received two applications (Day 0 and Day 7) of the allocated pediculicide shampoo, following the manufacturer's instructions. The final proportion of cured individuals was assessed on Day 14 after treatment using a fine-tooth comb. The observed percentages of cured individuals were 42.22% for carbaryl shampoo, 24.44% for Stemona shampoo, and 6.67% for permethrin shampoo. No side effects were reported, although none of the shampoos achieved complete eradication, with particularly poor outcomes in children with heavy infestations. These findings provide clinical evidence of reduced efficacy of over-the-counter pediculicides in Thailand, consistent with emerging resistance trends. More effective alternatives with different mechanisms of action, including ivermectin, abametapir, and dimeticone-based products, should be considered, although their current availability in Thailand remains limited. In the interim, development of locally available herbal formulations, together with school-based screening and simultaneous treatment, represents more feasible strategies. These results highlight the need for updated treatment guidelines, restriction of ineffective products, and regular resistance surveillance to ensure effective control.

A survey was conducted across 11 provinces in Northern Vietnam to investigate the distribution of Dollfustrema bagarii metacercariae - a causative agent of significant losses in cultured channel catfish (Ictalurus punctatus) - and to identify its first intermediate host. A total of 337 fish specimens were collected from 103 farms. Metacercariae of D. bagarii were detected in 72 farms (69.9% of farms), and 44.51% of the sampled fish were positive. The prevalence in lowland provinces was 3.14 times higher than that in mountainous regions (p < 0.001), while no significant difference was observed between fish cultured in reservoir/lake and those in river (p = 0.634). We identified the golden mussel Limnoperna fortunei (Bivalvia: Mytilidae) as the first intermediate host of D. bagarii. The morphological characteristics of its daughter sporocyst and cercariae were described, and the identification was confirmed through comparison of 28 S rDNA sequences with those of D. bagarii.

Sparganosis is a parasitic zoonosis caused by the larval plerocercoid (sparganum) of tapeworms in the genus Spirometra. Humans become infected by ingesting raw or undercooked meat from second intermediate or paratenic hosts such as frogs, snakes, and wild boars by drinking water contaminated with cyclopoid copepods carrying the larval procercoid, or by applying frog meat poultices. The gold standard for diagnosis remains the molecular confirmation of plerocercoids in surgically removed specimens. However, because these larvae migrate in subcutaneous tissues and the central nervous system elicit a strong IgG antibody response, serological tests can provide valuable diagnostic support. Although several IgG antibody detection assays have been developed, they are often time consuming and require sophisticated equipment. To overcome these limitations, we developed an immunochromatography based diagnostic kit termed the "sparganosis whole-blood test kit" that employs a gold labeled secondary antibody and can be used directly on either whole blood or serum samples. When tested on simulated whole blood specimens, the kit achieved 100% sensitivity and 91.6% specificity; in paired serum samples, sensitivity and specificity were 100.0% and 84.1%, respectively. This rapid, user-friendly test can facilitate bedside diagnosis in high-risk populations (e.g., hospitalized patients), serve as a point-of-care tool in remote areas with limited medical infrastructure, and offer a noninvasive alternative when biopsy or excision is impractical.

Toxoplasmosis is a food- and waterborne zoonosis of a great importance, ranked as the fourth most important foodborne parasitosis in the world. The objective of this study was to determine the seroprevalence and molecular prevalence of Toxoplasma gondii in wild boar (Sus scrofa) and to identify genotypes circulating in Croatia. A total of 103 wild boars from four hunting areas in Croatia were screened. Cardiac fluid samples were tested for anti-T. gondii antibodies by MAT, while heart samples were tested for T. gondii DNA using qPCR. The seroprevalence in the cardiac fluid reached 54.4%, while 19.4% of the heart samples were positive by qPCR. The highest seroprevalence was detected in the hunting ground Visocica with 95.6%. Partial microsatellite genotyping was achieved for 2/20 qPCR-positive heart samples suggesting type II strain of T. gondii. Relatively high seroprevalence and detection of T. gondii DNA in tested samples highlights the risk of human infection through consumption of undercooked meat. Further studies focusing on parasite detection in wild boar meat, especially across different climates, are needed to understand regional differences. Expanding research to other wildlife species is also important to clarify their role in the spread of T. gondii.

Alveolar echinococcosis (AE) is a rare but severe zoonosis caused byEchinococcus multilocularis that predominantly affects the liver. While previous studies have focused on single ultrasound patterns, the significance of hepatic double pattern lesions is not yet fully understood. The aim of this study is to investigate the prevalence, characteristics and combinations of sonographic double patterns in AE. Based on data from Germany's national echinococcosis database (n=825),40 patients with AE and confirmed double pattern were analysed retrospectively. Inclusion criteria were patients with at least two hepatic lesions of different patterns on reference ultrasound (US). US images were evaluated using the Echinococcosis Multilocularis Ulm Classification (EMUC)-US classification, with the analysis conducted by independent, blinded sonographers. Overall, a double pattern was detected in 4.8 % of patients (n=40). Ten different pattern combinations between two different patterns were observed, with the hailstorm and ossification patterns being the most common combination (52.2 %). Pattern combinations of up to four patterns were found in a single patient. A statistically significant correlation between the pattern combination and lesion activity, as determined by ¹⁸FDG-PET/CT and serological markers, could not be demonstrated. Sonographic double pattern manifestations of AE are rare. Currently, the occurrence of specific patterns and their combinations does not correlate with lesion activity. Further studies with larger sample sizes are needed to better understand the significance of double patterns and their potential prognostic value.

The European sardine, Sardina pilchardus (Walbaum, 1792) is one of the most abundant small pelagic clupeids and holds significant commercial value. Adult specimens were obtained along the Western and Southern Iberia, covering three ICES sub-divisions: 9aCN-Northerwestern Iberia, 9aCS-Southern Iberia and 9aS-South Iberia. A parasitological survey was carried out to characterize sardine parasite fauna and to assess its potential as a proxy for the spatial distribution of free-living parasite biodiversity and sardine trophic interactions, based on parasite richness and diversity. Parasites were analysed in different host organs and tissues. Fourteen parasite taxa were identified, which include Apicomplexa, Myxozoa, Monogenea, Digenea, Cestoda, Nematoda and Acanthocephala. Species diversity was higher in the Digenea group with a total of 2 116 specimens recorded. The Monogenea, Mazocraes alosae; the Cestoda, Scolex pleuronectis; the Acanthocephala, Rhadinorhynchus sp. and the Nematoda, Anisakis sp. and Hystherothylacium sp. larvae were also identified. This is the first study to investigate the relationship between parasite assemblages and diet composition in sardines from the Atlanto-Iberian coast. The finding highlight the potential of parasite fauna as indicator of food webs structure, free living parasite biodiversity and ecosystem stress, providing insights into differences observed among ICES sub-divisions. Both qualitative and quantitative variations in sardines' parasite comunities from the three ICES sub-divisions are in line with the differences observed in their prey composition, reflecting fine-scale trophic interactions linking parasites with intermediate and paratenic hosts present in the sardine diet.