• Parasites, Hosts and Diseases
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• v.56 no.3
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• pp.295-300
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• 2018

Human sparganosis was diagnosed by morphological and genetic analyses in Korea. The complete mitochondrial genomes of Spirometra erinaceieuropaei and S. decipiens isolated in Korea have been recorded. Present study was performed to provide information to diagnose the etiologic agent of sparganosis by multiplex PCR using mitochondrial genome sequences of S. erinaceieuropaei and S. decipiens. In an effort to examine the differential diagnosis of spirometrid tapeworms, multiplex PCR assays were performed on plerocercoid larvae of S. erinaceieuropaei and S. decipiens. The PCR products obtained using species-specific primers were positively detected in all PCR assays on mixture of S. erinaceieuropaei and S. decipiens DNA. S. erinaceieuropaei-specific bands (239 bp and 401 bp) were obtained from all PCR assays using a mixture of S. erinaceieuropaei-specific primers (Se/Sd-1800F and Se-2018R; Se/Sd-7955F and Se-8356R) and S. erinaceieuropaei template DNA. S. decipiens-specific bands (540 bp and 644 bp) were also detected in all PCR assays containing mixtures of S. decipiens-specific primers (Se/Sd-1800F and Sd-2317R; Se/Sd-7955F and Sd-8567R) and S. decipiens template DNA. Sequence analyses on these species-specific bands revealed 100% sequence identity with homologous regions of the mtDNA sequences of S. erinaceieuropaei and S. decipiens. The multiplex PCR assay was useful for differential diagnosis of human sparganosis by detecting different sizes in species-specific bands.

• Parasites, Hosts and Diseases
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• v.57 no.1
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• pp.55-60
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• 2019

This study was undertaken to determine the complete mitochondrial DNA sequence and structure of the mitochondrial genome of Spirometra ranarum, and to compare it with those of S. erinaceieuropaei and S. decipiens. The aim of this study was to provide information of the species level taxonomy of Spirometra spp. using the mitochondrial genomes of 3 Spirometra tapeworms. The S. ranarum isolate originated from Myanmar. The mitochondrial genome sequence of S. ranarum was compared with that of S. erinaceieuropaei (GenBank no. KJ599680) and S. decipiens (GenBank no. KJ599679). The complete mtDNA sequence of S. ranarum comprised 13,644 bp. The S. ranarum mt genome contained 36 genes comprising 12 protein-coding genes, 22 tRNAs and 2 rRNAs. The mt genome lacked the atp8 gene, as found for other cestodes. All genes in the S. ranarum mitochondrial genome are transcribed in the same direction and arranged in the same relative position with respect to gene loci as found for S. erinaceieuropaei and S. decipiens mt genomes. The overall nucleotide sequence divergence of 12 protein-coding genes between S. ranarum and S. decipiens differed by 1.5%, and 100% sequence similarity was found in the cox2 and nad6 genes, while the DNA sequence divergence of the cox1, nad1, and nad4 genes of S. ranarum and S. decipiens was 2.2%, 2.1%, and 2.6%, respectively.

• Parasites, Hosts and Diseases
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• v.59 no.2
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• pp.179-182
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• 2021

Human infection with Taenia asiatica or a hybrid between Taenia saginata and T. asiatica has not been reported in Cambodia. We detected for the first time a hybrid form between T. saginata and T. asiatica in Preah Vihear Province, Cambodia. An adult tapeworm specimen, i.e., 75 cm long strobila without scolex, was expelled from a 27-year-old man after praziquantel medication and purging. It was morphologically indistinguishable between T. saginata and T. asiatica. Several proglottids were molecularly analyzed to confirm the tapeworm species. The mitochondrial gene encoding cytochrome c oxidase subunit 1 (cox1) and nuclear genes encoding elongation factor-1α (ef1) and ezrin-radixin-moesin (ERM)-like protein (elp) were sequenced, and a single-allele analysis was performed to confirm the haploid genotype. The results revealed that our sample showed a discrepancy between the mitochondrial and 2 nuclear genes. It possessed homozygous sequences typical of T. saginata at cox1 and ef1 loci. However, it was heterozygous at the elp locus, with 1 allele in T. asiatica (elpA) and 1 in T. saginata (elpC), which indicates that it is a hybrid between T. saginata and T. asiatica. The present results confirmed the presence of a hybrid between T. saginata and T. asiatica in Cambodia and strongly suggest the existence of also 'pure' T. asiatica in Cambodia.

• Biomedical Science Letters
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• v.11 no.2
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• pp.153-163
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• 2005

To clarify the species validity of the genus Spirometra, the biological characteristics of Spirometra erinacei and S. mansonoides by developmental stages were compared. Their experimental life cycles were maintained under the same laboratory conditions, and the biological characteristics were experimentally observed in vivo and in vitro conditions. Eggs of S. erinacei and S. mansonoides were $59.6\pm35.6{\mu}m\;and\;61.4\pm35.8{\mu}m$ in each average size. Both of them became fully matured and hatched in 8 days after incubation at $29^{\circ}C$. The coracidium of S. erinacei was $43.6\times35.8{\mu}m$ in average size, and retained a oncosphere of $39.3\times31.0{\mu}m$. That of S. mansonoides was $43.0\times36.3{\mu}m$ in average size, and retained a oncosphere of $38.3\times30.8{\mu}m$. Procercoids of S. erinacei were somewhat larger than those of S. mansonoides. Both species of procercoids older than 7 days in cyclops had minute spines at the anterior end, calcium corpuscles in the parenchyme and a cercomer at the posterior end. The procercoids older than 4 days in cyclops were infective to tadpoles. The procercoids older than 8 days revealed the infectivity to mice. Plerocercoids of S. erinacei were somewhat lager than those of S. mansonoides when they were compared by age of worms in tadpoles. Both species of plerocercoids older than 5 days were infective to mice. Among 138 plerocercoids of S. erinacei recovered from the experimental mice, $55(39.9\%)$ were detected in the neck portion, $35 (25.4\%)$ in the back portion, $25(18.1\%)$ in the anterior legs, and $23 (16.7\%)$ were found in the abdomen. In case of S. mansonoides plerocercoids, $42.0\%$ were found in the neck portion, $23.8\%$ in the back portion, $14.4\%$ in the abdomen, $13.3\%$ in the anterior legs, and $6.1\%$ were found in the posterior legs. From the above results, it was confirmed that the biological characteristics of S. erinacei and S. mansonoides are almost same when their life cycles are mainteined under the same laboratory condition. Accordingly, these findings suggest that S. erinacei and S. mansonoides may be the same species.

• Parasites, Hosts and Diseases
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• v.53 no.3
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• pp.299-305
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• 2015

Tapeworms of the genus Spirometra are pseudophyllidean cestodes endemic in Korea. At present, it is unclear which Spirometra species are responsible for causing human infections, and little information is available on the epidemiological profiles of Spirometra species infecting humans in Korea. Between 1979 and 2009, a total of 50 spargana from human patients and 2 adult specimens obtained from experimentally infected carnivorous animals were analyzed according to genetic and taxonomic criteria and classified as Spirometra erinaceieuropaei or Spirometra decipiens depending on the morphology. Morphologically, S. erinaceieuropaei and S. decipiens are different in that the spirally coiled uterus in S. erinaceieuropaei has 5-7 complete coils, while in S. decipiens it has only 4.5 coils. In addition, there is a 9.3% (146/1,566) sequence different between S. erinaceieuropaei and S. decipiens in the cox1 gene. Partial cox1 sequences (390 bp) from 35 Korean isolates showed 99.4% (388/390) similarity with the reference sequence of S. erinaceieuropaei from Korea (G1724; GenBank KJ599680) and an additional 15 Korean isolates revealed 99.2% (387/390) similarity with the reference sequences of S. decipiens from Korea (G1657; GenBank KJ599679). Based on morphologic and molecular databases, the estimated population ratio of S. erinaceieuropaei to S. decipiens was 35: 15. Our results indicate that both S. erinaceieuropaei and S. decipiens found in Korea infect humans, with S. erinaceieuropaei being 2 times more prevalent than S. decipiens. This study is the first to report human sparganosis caused by S. decipiens in humans in Korea.

• Biomedical Science Letters
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• v.4 no.1
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• pp.65-72
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• 1998

Recently there have been frequent reports on human infection caused by the Diphyllobothridae in Korea. The adequate opportunities for Koreans to eat raw fish, the primary infection medium of cestodes and the human infection through drinking water by cyclops, the first intermediate host are believed to be main reasons for the infection. The first task of this study was to classify and diagnose the species by differentiating morphological characteristic between scolex and proglottids of cestodes. However, the initially available diagnosis was done with the patient's symptoms and the eggs obtained from his stool. It is important to differentiate the species by the eggs of Diphyllobothrium latum especially in that it can help get advance information for a more reliable analysis in the near future. The morphological and diagnostic results from proglottids and eggs of Diphyllobothrium latum, Diphyllobothrium latum parvum and Spirometra erinacei are as follows； In each kind of cestodes from the patient's stool, the shape and size of 50 eggs were measured. Eggs of Diphyllobothrium latum had an operculum and were ovoidal or ellipsoid to elliptical in shape. Eggs of Diphyllobothrium latum parvum were more ovoidal in shape and smaller in size than Diphyllobothrium latum. And eggs of Spirometra erinacei were asymmetrical in width and long and slender in shape. The average lengths and widths of Diphyllobothrium latum, Diphyllobothrium latum parvum and Spirometra erinacei were 61.4$\times$41.7 $\mu\textrm{m}$, 55.9$\times$41.4 $\mu\textrm{m}$ and 66.7$\times$36.4 $\mu\textrm{m}$, respectively. After the segments of each cestode were fixed, embedding and hematoxylin-eosin dyeing on a microtome-made specimen were done. The micrographs of the semicon's aceto-carmine dyed specimen showed that Diphyllobothrium latum and Diphyllobothrium latum parvum had a centrally-located genital gland and an opened uterine pore. The yolks were observed on both sides of proglottids and had a typical rosette pattern. Yet, Diphyllobothrium latum parvum was shown smaller than Diphyllobothrium latum in the micrograph. Proglottids of Spirometra erinacei displayed that the uterus was rolled spirally more than five to seven times, and connected successively to the seminal vesicle in the cirrus sac. Shown above, this study was performed to measure the size of eggs and analyze the morphological characteristics of proglottids and provided the measurements of three types of cestodes obtained by a light microscope.