Neurocysticercosis: A case study of a Mongolian traveler who visited China and India with an updated review in Asia.

BACKGROUND: Neurocysticercosis (NCC) of Taenia solium has never been reported in Mongolia. A Mongolian traveler who visited China and India presented with epileptic seizures after his return to Mongolia. Magnetic resonance imaging showed multiple ring enhancing lesions with edema surrounding several lesions in his brain that were initially diagnosed to be viral encephalitis or NCC. METHODS: Serology for cysticercosis using diagnostic antigens partially purified by cation-exchange chromatography and chimeric recombinant antigens and DNA analysis of a proglottid found in the patient's stool were applied for differential diagnosis. RESULTS: Serology showed strong positivity for NCC, and mitochondrial cox1 gene analysis revealed Indian but not Chinese haplotype of T. solium. CONCLUSION: This NCC case was considered to be caused by eggs released from adult tapeworm(s) established after eating uncooked or undercooked pork contaminated with cysticerci during his stay in India. This is a case report of taeniasis and secondary NCC associated with travel to India with an updated review of NCC in Asia. Molecular tracking of the specimen is highly informative as a way to identify where the infection was acquired.

Cystic echinococcoses in Mongolia: molecular identification, serology and risk factors.

BACKGROUND: Cystic echinococcosis (CE) is a globally distributed cestode zoonosis that causes hepatic cysts. Although Echinococcus granulosus sensu stricto (s.s.) is the major causative agent of CE worldwide, recent molecular epidemiological studies have revealed that E. canadensis is common in countries where camels are present. One such country is Mongolia. METHODOLOGY/PRINCIPAL FINDINGS: Forty-three human hepatic CE cases that were confirmed histopathologically at the National Center of Pathology (NCP) in Ulaanbaatar (UB) were identified by analysis of mitochondrial cox 1 gene as being caused by either E. canadensis (n=31, 72.1%) or E. granulosus s.s. (n=12, 27.9%). The majority of the E. canadensis cases were strain G6/7 (29/31, 93.5%). Twenty three haplotypes were identified. Sixteen of 39 CE cases with data on age, sex and province of residence were citizens of UB (41.0%), with 13 of the 16 cases from UB caused by E. canadensis (G6/7) (81.3%). Among these 13 cases, nine were children (69.2%). All pediatric cases (n  =  18) were due to E. canadensis with 17 of the 18 cases (94.4%) due to strain G6/7. Serum samples were available for 31 of the 43 CE cases, with 22 (71.0%) samples positive by ELISA to recombinant Antigen B8/1 (rAgB). Nine of 10 CE cases caused by E. granulosus s.s. (90.0%) and 13 of 20 CE cases by E. canadensis (G6/7) (65.0%) were seropositive. The one CE case caused by E. canadensis (G10) was seronegative. CE cases caused by E. granulosus s.s. showed higher absorbance values (median value 1.131) than those caused by E. canadensis (G6/7) (median value 0.106) (p  =  0.0137). CONCLUSION/SIGNIFICANCE: The main species/strains in the study population were E. canadenis and E. granulossus s.s. with E. canadensis the predominant species identified in children. The reason why E. canadensis appears to be so common in children is unknown.

Recent situation of taeniasis in Mongolia (2002-2012).

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.

Molecular Detection and Seroprevalence of Babesia microti among Stock Farmers in Khutul City, Selenge Province, Mongolia

Babesiosis is an emerging tick-borne disease in humans worldwide; however, little is known about the frequency of infection or prevalence of this disease in other parts of the world, excluding North America. In this study, we aimed to investigate Babesia microti infection frequency in a human population in Mongolia. One hundred blood samples were collected from stock farmers living in Khutul city of Selenge province, Mongolia. The sera and DNA from blood samples were evaluated for the presence of B. microti infection by using indirect fluorescent antibody (IFA) tests and PCR. The positive detection rates obtained using the IFA tests and PCR assays were 7% and 3%, respectively. This study is the first to detect of B. microti infections based on antibody seroprevalence or PCR assays for the presence of B. microti DNA in a Mongolian population.

Echinococcus species from red foxes, corsac foxes, and wolves in Mongolia.

The small intestines of 420 wild canids (111 corsac foxes, 191 red foxes and 118 wolves) from Mongolia, were examined for adult worms of the genus Echinococcus. The Mongolian genotype of Echinococcus multilocularis was found in fifteen red foxes and four wolves, whereas two genotypes (G6/7 and G10) of Echinococcus canadensis were found in two and three wolves, respectively. No adult Echinococcus worms were found in the corsac foxes examined. The genotypes of E. multilocularis and E. canadensis are discussed in terms of host specificity and distribution in Mongolia. The importance of wolves in the completion of the life cycle of Echinococcus spp. is also discussed.

Histopathological, serological, and molecular confirmation of indigenous alveolar echinococcosis cases in Mongolia.

Alveolar echinococcosis cases diagnosed histopathologically in 2002, 2006, 2007, and 2009 in Ulaanbaatar, Mongolia were reconfirmed by evaluating the cytochrome c oxidase subunit I gene of mitochondrial DNA. The most recent three cases using paraffin-embedded and ethanol-fixed specimens revealed that one was of the "Asian" haplotype, whereas two others were of the "Inner Mongolian" type. All patients were born in the western provinces of Mongolia, they never resided outside of Mongolia, and they were given a preliminary diagnosis of malignant hepatic tumor or abscess. The most recent two cases were also confirmed serologically to be active alveolar echinococcosis.

Taeniasis in Mongolia, 2002-2006.

Survey on secondary data of taeniasis/cysticercosis was carried out in Mongolia in 2002-2006. A total of 118 taeniid proglottids, a diphyllobothriid segment, and 59 serum samples from 118 taeniasis cases were collected at National Center for Communicable Diseases, Ulaanbaatar, Mongolia. In 2006, 14 serum samples were collected from local people who had histories of epileptic seizures in Selenge Province where pig husbandry was the main business. The 118 proglottids were confirmed to be Taenia saginata by mitochondrial DNA analysis using cytochrome c oxidase subunit 1 and cytochrome b genes. T. saginata taeniasis was widely distributed at least in 10 of 21 provinces. No variation in the nucleotide sequences of the two genes was observed among T. saginata isolates from Mongolia. There was no evidence of Taenia solium taeniasis/cysticercosis or Taenia asiatica taeniasis. A diphyllobothriid segment was confirmed to be Diphyllobothrium latum by mitochondrial DNA analysis.