• Parasites, Hosts and Diseases
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• v.51 no.1
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• pp.9-17
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• 2013

History and current status of human taeniasis in the Republic of Korea, due to Taenia solium, Taenia asiatica, and Taenia saginata, are briefly reviewed. Until the 1980s, human taeniasis had been quite common in various localities of Korea. A study from 1924 reported 12.0% egg prevalence in fecal examinations. Thereafter, the prevalence of Taenia spp. ranged from 3% to 14% depending on the time and locality. Jeju-do, where pigs were reared in a conventional way, was the highest endemic area of taeniasis. An analysis of internal transcribed spacer 2 and mitochondrial cytochrome c oxidase 1 genes of 68 taeniasis cases reported from 1935 to 2005 in Korea by a research group revealed the relative occurrence of the 3 Taenia spp. as follows: T. solium (4.4%), T. asiatica (75.0%), and T. saginata (20.6%). However, national surveys on intestinal helminths conducted every 5 years on randomly selected people revealed that the Taenia egg prevalence dropped from 1.9% in 1971 to 0.02% in 1997 and finally to 0.0% in 2004. With the exception of 3 egg-positive cases reported in 2008 and 2 worm-proven cases in 2011, no more cases have been officially recorded. Based on these surveys and also on other literature, it can be concluded that taeniasis has virtually disappeared from Korea, although a few sporadic cases may remain hidden. Human cysticercosis is also expected to disappear within a couple of decades in Korea.

• Parasites, Hosts and Diseases
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• v.52 no.2
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• pp.125-129
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• 2014

Several reports on taeniasis and cysticercosis in Vietnam show that they are distributed in over 50 of 63 provinces. In some endemic areas, the prevalence of taeniasis was 0.2-12.0% and that of cysticercosis was 1.0-7.2%. The major symptoms of taeniasis included fidgeted anus, proglottids moving out of the anus, and proglottids in the feces. Clinical manifestations of cysticercosis in humans included subcutaneous nodules, epileptic seizures, severe headach, impaired vision, and memory loss. The species identification of Taenia in Vietnam included Taenia asiatica, Taenia saginata, and Taenia solium based on combined morphology and molecular methods. Only T. solium caused cysticercosis in humans. Praziquantel was chosen for treatment of taeniasis and albendazole for treatment of cysticercosis. The infection rate of cysticercus cellulosae in pigs was 0.04% at Hanoi slaughterhouses, 0.03-0.31% at provincial slaughterhouses in the north, and 0.9% in provincial slaughterhouses in the southern region of Vietnam. The infection rate of cysticercus bovis in cattle was 0.03-2.17% at Hanoi slaughterhouses. Risk factors investigated with regard to transmission of Taenia suggested that consumption of raw meat (eating raw meat 4.5-74.3%), inadequate or absent meat inspection and control, poor sanitation in some endemic areas, and use of untreated human waste as a fertilizer for crops may play important roles in Vietnam, although this remains to be validated.

• Parasites, Hosts and Diseases
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• v.51 no.1
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• pp.19-29
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• 2013

This mini-review describes recent epidemiological trends in cysticercosis and taeniasis in Japan. Some of the topics discussed herein were presented at the first symposium on "Current perspectives of Taenia asiatica researches", that was held in Osong in Chungbuk Province, South Korea, in October 2011 and organized by Prof. K. S. Eom, Chungbuk National University School of Medicine. To better understand the trends in the occurrence of cysticercosis and taeniasis in Japan, clinical cases reported in 2005 have been updated. In addition, the current status of Taenia asiatica infections successively occurring in Japan since 2010 is also discussed.

• Parasites, Hosts and Diseases
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• v.52 no.2
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• pp.211-214
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• 2014

Epidemiological situation of taeniasis in Mongolia was assessed based on mitochondrial DNA identification of the parasite species. Multiplex PCR was used on a total of 194 proglottid specimens of Taenia species and copro-PCR and loop-mediated isothermal amplification (LAMP) assays were utilized for detection of copro-DNA of 37 fecal samples from taeniasis patients submitted to the Mongolian National Center for Communicable Diseases (NCCD) from 2002 to 2012. In addition, 4 out of 44 calcified cysts in beef kept in formalin since 2003 were evaluated for histopathological confirmation of cattle cysticercosis. All proglottid specimens and stool samples were confirmed to be Taenia saginata by multiplex PCR and by copro-PCR and LAMP, respectively. Cysts collected from cattle were morphologically confirmed to be metacestodes of Taenia species. T. saginata taeniasis was identified from almost all ages from a 2-year-old boy up to a 88-year-old woman and most prominently in 15-29 age group (37%, 74/198) followed by 30-44 age group (34.8%, 69/198 ) from 15 of Mongolia's 21 provinces, while cattle cysticerci were found from 12 provinces. The highest proportion of taeniasis patients was in Ulaanbaatar, the capital of Mongolia.

• Parasites, Hosts and Diseases
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• v.51 no.1
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• pp.51-54
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• 2013

Not only Taenia solium and Taenia saginata, but also Taenia asiatica infects humans. The last species is not included in the evaluation of the specificity of the immunodiagnostic techniques for taeniasis/cysticercosis. There is currently no specific immunodiagnostic method for T. asiatica available. Therefore, due to the fact that molecular techniques (the only tool to distinguish the 3 Taenia species) are normally not employed in routine diagnostic methods, the 2 questions concerning T. asiatica (its definite geographic distribution and its ability to cause human cysticercosis), remain open, turning T. asiatica into the most neglected agent of human taeniasis-cysticercosis.

• Parasites, Hosts and Diseases
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• v.57 no.3
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• pp.313-318
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• 2019

In recent years, the taeniasis has been rarely reported in the Republic of Korea (Korea). But in this study, we intend to report 4 taeniasis cases caused by Taenia saginata during a 5-month period (February to June 2018) at a unversity hospital in Gwangju, Korea. Worm samples (proglottids) discharged from all cases were identified by phenotypic and molecular diagnostics. Mitochondrial cytochrome c oxidase subunit I sequences showed 99.4-99.9% identity with T. saginata but, differed by 4% from T. asiatica and by 7% from T. multiceps, respectively. We found that tapeworms in 2 cases (Cases 2 and 3) yielded exactly the same sequences between them, which differed from those in Cases 1 and 4, suggesting intra-species variation in tapeworms. These taeniasis cases by T. saginata infection in this study, which occurred within a limited time period and region, suggest the possibility of a mini-outbreak. This study highlights the need for further epidemiological investigation of potentially overlooked cases of T. saginata infection in Korea.

• Parasites, Hosts and Diseases
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• v.51 no.1
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• pp.31-36
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• 2013

An overview of the epidemiological, biological, and clinical studies of Taenia and taeniasis in Taiwan for the past century is presented. The phenomenal observations that led to the discovery of Taenia asiatica as a new species, which differ from Taenia solium and Taenia saginata, are described. Parasitological surveys of the aborigines in Taiwan revealed a high prevalence of taeniasis, which might be due to the culture of eating raw liver of hunted wild boars. Chemotherapeutic deworming trials involving many patients with taeniasis were discussed. Praziquantel was found to be very effective, but sometimes complete worms could not be recovered from the feces after treatment, probably due to the dissolution of the proglottids. Atabrine, despite some side effects, can still be used, in properly controlled dosages, as the drug of choice for human T. asiatica infection if we need to recover the expelled worms for morphological examinations. Research results on the infection of T. asiatica eggs from Taiwan aborigines in experimental animals were also noted. Since the pig serve as the natural intermediate host of T. asiatica and the predilection site is the liver, a differential comparison of other parasitic pathogens that might cause apparently similar lesions is also presented.

• Parasites, Hosts and Diseases
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• v.59 no.4
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• pp.369-376
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• 2021

Several factors presumed to facilitate the transmission of Taenia spp. were reported in Vietnam. We conducted a cross-sectional study taking questionnaires from 1,185 participants, and collecting 1,151 sera and 1,036 stool samples in northern Vietnam. Sera were examined for circulating antigens of Taenia solium cysticerci using ELISA, stools for Taenia eggs by Kato-Katz smear, and copro-antigens by ELISA. Ag-ELISA revealed 4.6% antigen positivity, indicating infection with viable cysticerci. Taenia eggs were detected in 1.5% of participants. Copro-antigens were found in 2.8% of participants. Eating raw meat and/or vegetables was significantly associated with the presence of copro-antigen (OR=8.6, 95% CI: 1.16-63.9, P=0.01). Considering the high taeniasis prevalence and the associated threat, public health attention should be given to treat the tapeworm carriers in the projected areas.

• Parasites, Hosts and Diseases
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• v.47 no.1
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• pp.73-77
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• 2009

Differential diagnosis of Taenia asiatica infection from other human taeniases by serology has been tested. An enzyme-linked immunoelectrotransfer blot (EITB) was applied to subjected human sera and tapeworm materials. Thirty-eight proteins reactive to serum IgG were observed between 121 and 10 kDa in adult worms, and more than 22 serum-reactive components between 97kDa and 21.5kDa were observed in eggs of T. asiatica. Antigens of adult T. asiatica revealed immunoblot bands between 120 and 21.5 kDa against T. asiatica infected sera. Antigens of adult Taenia saginata revealed 110-100, 66, 58-56, and 46 kDa immunoblot bands against T. asiatica infected sera. Antigens of adult Taenia solium also revealed 99-97, 68-66, and 46 kDa bands against T. asiatica infected sera. The immunoblot band of 21.5 kDa exhibited specificity to T. asiatica.

• Parasites, Hosts and Diseases
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• v.51 no.1
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• pp.37-42
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• 2013

Taeniasis is prevalent in all regions of Thailand, except the South. Infections were more frequently found in males than females of any age from 7-83 years. Taenia saginata is the most common species throughout the country. Taenia asiatica was reported only in the province of Kanchanaburi in the Central region. Co-infections, with Taenia solium and T. asiatica or T. solium and T. saginata, were found. Hybridization between T. asiatica and T. saginata is evidence that co-infection is never found between these 2 species. Finding more than 1 worm in a single patient was not entirely rare. Genetic variation was found without correlation to its geographic distribution in T. saginata, whereas no variation was found in T. asiatica.