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A survey was carried out to determine the prevalence and seasonal abundance of Haemonchus contortus in the semi arid zone of Uttar Pradesh, India between January 2010 to December 2013. Entire gastrointestinal tract from slaughtered goats were brought to the laboratory. Parasites were collected from the abomasum, counted and recorded on monthly basis. The collected data were analyzed on the basis of temperature, rainfall and humidity of the months/seasons. Out of total 635 goats, 383 (60%) were found to be infected with H. contortus. The mean intensity and abundance was found as 354 and 263 respectively. Marked variations in the prevalence, mean intensity and abundance were noticed during different month/season of the year. Highest values of these infection indices were found in the rainy season and lowest in summer. Although prevalence, intensity and abundance were positively correlated with temperature, rainfall and humidity but only the effect of rainfall was found to be statistically significant. The present study provides a consolidated account on the seasonal dynamics of H. contortus , which can be used for integrated control measures of this blood sucking parasite under local environment conditions. [ABSTRACT FROM AUTHOR]

Background: Stray dogs are considered potential reservoirs for zoonotic diseases. Previous helminthic surveys in Iran, have accounted for mainly species of nematodes and cestodes, and rarely digeneans. Methods: We accessed 42 car-crashed stray dogs from the Farah Abad Region in the Mazandaran Province (North Iran) between Oct 2012 and Dec 2013, to be inspected for parasites. Helminths were collected from the intestine and they were morphologically studied. Results: We found five adult digeneans from the family Brachylaimidae, identified as Brachylaima sp. Worms were assigned to the genus based on the shape of the body, the position of genital pore, cirrus sac and testes, and the extension of the vitellarium. Absence of additional information on the developmental stages of the parasite precluded its specific identification. As the geographic distribution of species of Brachylaima is restricted to the Mediterranean region, we raise the hypothesis that dogs may become infected with parasites through the consumption of helicid snails when searching for food on the street. Conclusion: This is the second report of a species of Brachylaima in Iran and the third digenean species from stray dogs in the area. We want to raise the attention of researchers to helminthic surveys in potential zoonotic reservoirs like stray dogs. [ABSTRACT FROM AUTHOR]

Tapeworms of the species complex of Echinococcus granulosus sensu lato (s. l.) are the cause of a severe zoonotic disease – cystic echinococcosis, which is listed among the most severe parasitic diseases in humans and is prioritized by the World Health Organization. A stable taxonomy of E. granulosus s. l. is essential to the medical and veterinary communities for accurate and effective communication of the role of different species in this complex on human and animal health. E. granulosus s. l. displays high genetic diversity and has been divided into different species and genotypes. Despite several decades of research, the taxonomy of E. granulosus s. l. has remained controversial, especially the species status of genotypes G6–G10. Here the Bayesian phylogeny based on six nuclear loci (7387 bp in total) demonstrated, with very high support, the clustering of G6/G7 and G8/G10 into two separate clades. According to the evolutionary species concept, G6/G7 and G8/G10 can be regarded as two distinct species. Species differentiation can be attributed to the association with distinct host species, largely separate geographical distribution and low level of cross-fertilization. These factors have limited the gene flow between genotypic groups G6/G7 and G8/G10, resulting in the formation of distinct species. We discuss ecological and epidemiological differences that support the validity of these species. [ABSTRACT FROM AUTHOR]

Abstract Cystic echinococcosis (CE), a zoonotic disease caused by tapeworms of the species complex Echinococcus granulosus sensu lato, represents a substantial global health and economic burden. Within this complex, E. granulosus sensu stricto (genotypes G1 and G3) is the most frequent causative agent of human CE. Currently, there is no fully reliable method for assigning samples to genotypes G1 and G3, as the commonly used mitochondrial cox1 and nad1 genes are not sufficiently consistent for the identification and differentiation of these genotypes. Thus, a new genetic assay is required for the accurate assignment of G1 and G3. Here we use a large dataset of near-complete mtDNA sequences ( n = 303) to reveal the extent of genetic variation of G1 and G3 on a broad geographical scale and to identify reliable informative positions for G1 and G3. Based on extensive sampling and sequencing data, we developed a new method, that is simple and cost-effective, to designate samples to genotypes G1 and G3. We found that the nad5 is the best gene in mtDNA to differentiate between G1 and G3, and developed new primers for the analysis. Our results also highlight problems related to the commonly used cox1 and nad1. To guarantee consistent identification of G1 and G3, we suggest using the sequencing of the nad5 gene region (680 bp). This region contains six informative positions within a relatively short fragment of the mtDNA, allowing the differentiation of G1 and G3 with confidence. Our method offers clear advantages over the previous ones, providing a significantly more consistent means to distinguish G1 and G3 than the commonly used cox1 and nad1. Graphical abstract Unlabelled Image Highlights • We describe a reliable method to differentiate E. granulosus s. s. genotypes G1 and G3. • The analysis was based on a large global dataset of G1 and G3 sequences ( n = 303). • The novel genetic assay is based on the analysis of the partial nad5 gene (680 bp). • The 680 bp nad5 gene fragment comprises 6 diagnostic positions. • Novel primers EGnd5F1 and EGnd5R1 were designed. [ABSTRACT FROM AUTHOR]

Cystic echinococcosis (CE) is a severe parasitic disease caused by the species complex Echinococcus granulosus sensu lato. Human infections are most commonly associated with E. granulosus sensu stricto (s.s.), comprising genotypes G1 and G3. The objective of the current study was to provide first insight into the genetic diversity and phylogeography of genotype G3. Despite the epidemiological importance of the genotype, it has remained poorly explored due to the ambiguity in the definition of the genotype. However, it was recently demonstrated that long sequences of mitochondrial DNA (mtDNA) provide a reliable method to discriminate G1 and G3 from each other. Therefore, we sequenced near-complete mtDNA of 39 G3 samples, covering most of the known distribution range and host spectra of the genotype. The phylogenetic network revealed high genetic variation within E. granulosus s.s. G3 and while G3 is significantly less prevalent worldwide than G1, the genetic diversity of both of the genotypes is equally high. We also present the results of the Bayesian phylogeographic analysis, which yielded several well-supported diffusion routes of genotype G3 originating from Turkey and Iran, suggesting the Middle East as the origin of the genotype. [ABSTRACT FROM AUTHOR]

Echinococcus granulosus sensu stricto (s.s.) is the major cause of human cystic echinococcosis worldwide and is listed among the most severe parasitic diseases of humans. To date, numerous studies have investigated the genetic diversity and population structure of E. granulosus s.s. in various geographic regions. However, there has been no global study. Recently, using mitochondrial DNA, it was shown that E. granulosus s.s. G1 and G3 are distinct genotypes, but a larger dataset is required to confirm the distinction of these genotypes. The objectives of this study were to: (i) investigate the distinction of genotypes G1 and G3 using a large global dataset; and (ii) analyse the genetic diversity and phylogeography of genotype G1 on a global scale using near-complete mitogenome sequences. For this study, 222 globally distributed E. granulosus s.s. samples were used, of which 212 belonged to genotype G1 and 10 to G3. Using a total sequence length of 11,682 bp, we inferred phylogenetic networks for three datasets: E. granulosus s.s. ( n  = 222), G1 ( n  = 212) and human G1 samples ( n  = 41). In addition, the Bayesian phylogenetic and phylogeographic analyses were performed. The latter yielded several strongly supported diffusion routes of genotype G1 originating from Turkey, Tunisia and Argentina. We conclude that: (i) using a considerably larger dataset than employed previously, E. granulosus s.s. G1 and G3 are indeed distinct mitochondrial genotypes; (ii) the genetic diversity of E. granulosus s.s. G1 is high globally, with lower values in South America; and (iii) the complex phylogeographic patterns emerging from the phylogenetic and geographic analyses suggest that the current distribution of genotype G1 has been shaped by intensive animal trade. [ABSTRACT FROM AUTHOR]

Cystic echinococcosis, a zoonotic disease caused by Echinococcus granulosus sensu lato (s. l.), is a significant global public health concern. Echinococcus granulosus s. l. is currently divided into numerous genotypes (G1–G8 and G10) of which G1–G3 are the most frequently implicated genotypes in human infections. Although it has been suggested that G1–G3 could be regarded as a distinct species E . granulosus sensu stricto (s. s.), the evidence to support this is inconclusive. Most importantly, data from nuclear DNA that provide means to investigate the exchange of genetic material between G1–G3 is lacking as none of the published nuclear DNA studies have explicitly included G2 or G3. Moreover, the commonly used relatively short mtDNA sequences, including the complete cox1 gene, have not allowed unequivocal differentiation of genotypes G1–G3. Therefore, significantly longer mtDNA sequences are required to distinguish these genotypes with confidence. The main aim of this study was to evaluate the phylogenetic relations and taxonomy of genotypes G1–G3 using sequences of nearly complete mitogenomes (11,443 bp) and three nuclear loci (2984 bp). A total of 23 G1–G3 samples were analysed, originating from 5 intermediate host species in 10 countries. The mtDNA data demonstrate that genotypes G1 and G3 are distinct mitochondrial genotypes (separated by 37 mutations), whereas G2 is not a separate genotype or even a monophyletic cluster, but belongs to G3. Nuclear data revealed no genetic separation of G1 and G3, suggesting that these genotypes form a single species due to ongoing gene flow. We conclude that: (a) in the taxonomic sense, genotypes G1 and G3 can be treated as a single species E . granulosus s. s.; (b) genotypes G1 and G3 should be regarded as distinct genotypes only in the context of mitochondrial data; (c) we recommend excluding G2 from the genotype list. [ABSTRACT FROM AUTHOR]