Occurrence of Hymenolepis diminuta: a potential helminth of zoonotic importance in murid rodents / Ocorrência de Hymenolepis diminuta: um helminto potencial de importância zoonótica em roedores murídeos

The study reveals the prevalence of a potential rodent-borne zoonotic helminth species, Hymenolepis diminuta in commensal rodents caught from irrigated and rain-fed areas of Swat, Pakistan. Three hundred and fifty rodents (269 rats and 81 mice) trapped during vegetative, flowering/fruiting and mature/harvesting stages of crops were studied from 2011-2013. Hymenolepisdiminuta eggs were identified on the basis of their shape, size, colour and markings on the surface of the egg shell and three pairs of embryonic hook-lets. Overall prevalence of H. diminuta was 3.14% (n=11/350). The highest prevalence 3.49% (n=5/143) of H. diminuta was noted at harvesting stages of the crops whereas the lowest 2.59% (n=2/77) during vegetative stage. Infection was higher in males 3.25% (n=7/215) than females 2.96% (n=4/135). Adult rodents were highly infected while no sub-adult was found infected. Infection was higher in mice 3.70% (3/81) than rats 2.69% (8/269) while no significance (p=1.0000:0.1250 to 32.00 CI). Rats and mice appears to show the most suitable reservoirs by hosting H. diminuta a zoonotic helminth. The presence of these rodents in all possible habitats can act as a main channel of transferring parasites through various habitats and can pose a hazard to humans in the area.

O estudo revela a prevalência de uma espécie potencial de helmintos zoonóticos transmitidos por roedores, Hymenolepis diminuta, em roedores comensais capturados em áreas irrigadas e alimentadas pela chuva de Swat, Paquistão. Trezentos e cinquenta roedores (269 ratos e 81 camundongos) presos durante os estágios vegetativo, floração/frutificação e maturidade/colheita das safras foram estudados de 2011-2013. Ovos de Hymenolepisdiminuta foram identificados com base em sua forma, tamanho, cor e marcações na superfície da casca do ovo e três pares de anzóis embrionários. A prevalência geral de H. diminuta foi de 3,14% (n = 11/350). A maior prevalência 3,49% (n = 5/143) de H. diminuta foi observada na fase de colheita das lavouras, enquanto a menor 2,59% (n = 2/77) durante a fase vegetativa. A infecção foi maior nos homens 3,25% (n = 7/215) do que nas mulheres 2,96% (n = 4/135). Roedores adultos foram altamente infectados, enquanto nenhum subadulto foi encontrado infectado. A infecção foi maior em camundongos 3,70% (3/81) do que em ratos 2,69% (8/269), embora sem significância (p = 1,0000: 0,1250 a 32,00 CI). Ratos e camundongos parecem mostrar os reservatórios mais adequados hospedando H. diminuta um helmintos zoonótico. A presença desses roedores em todos os habitats possíveis pode atuar como um canal principal de transferência de parasitas através de vários habitats e pode representar um perigo para os humanos na área.

Himenolepiasis por Hymenolepis nana, a propósito de 2 casos / Hymenolepiasis due to Hymenolepis nana, in relation to 2 cases

La himenolepiasis es una infección parasitaria cosmopolita; su prevalencia global oscila entre 0.1 y 58%, es más frecuente en niños. El agente etiológico es el cestodo Hymenolepis nana, que evoluciona mediante ciclos vitales: monoxénico (en el cual existe un único huésped definitivo e intermediario que puede ser el ser humano, ratas y ratones) y un ciclo heteroxénico (en el que un artrópodo ­pulga o gorgojo­ consume los huevos presentes en las materias fecales y desarrolla el cisticercoide ­larva­). Este vector es ingerido por el huésped definitivo (humano o rata) desarrollando posteriormente la infección. Los síntomas dependerán del grado de afectación de las vellosidades del intestino delgado; se destacan: dolor abdominal, meteorismo, diarrea, irritabilidad, prurito anal y anorexia. El tratamiento de elección es el praziquantel 25 mg/kg dosis única. Presentamos 2 casos de usuarios adultos que acuden al Centro de Salud de San Antonio de Pichincha ­ Quito, con sintomatología inespecífica, a los que se les realiza examen coproparasitario como control al primero y como sospecha por contacto con roedor al segundo; en ambos casos se encuentra el parásito. Aunque se decide iniciar el tratamiento con praziquantel, no se lo consigue, por lo que se prescribe niclosamida 2 g por día durante 2 días; desapareció el cuadro sintomático y el parásito en el examen de control de laboratorio (AU)

Hymenolepiasis is a parasitic infection with a cosmopolitan distribution, it has a global prevalence ranging from 0.1 to 58%. Is more frequent in children and is produced by the Hymenolepis nana basket, which evolves through life cycles: monoxenic, with a single final host and an intermediate host, which can be a man, rats or mice. In the heterocyclic cycle, it's evident the presence of an arthropod (flea or weevil) that consumes eggs in fecal matter and develops the cysticercoid (larva). Then, this vector is ingested by the definitive host (human or rat) who is going to develop the infection subsequently. Symptoms depend on the degree of involvement of villi in the small intestine, including abdominal pain, bloating, diarrhea, irritability, anal pruritus and anorexia. The treatment of choice is praziquantel in a single dose of 25 mg. In the present work, we describe the cases of users who visited the Health Center of San Antonio de Pichincha in Quito. They came with nonspecific symptomatology. At first, they were analyzed through a coproparasitary examination of the control and the suspicion of contact with the rodent at second. In both cases with the pathology. It was decided to start the treatment. However, this medication was not obtained, so a dose of 2 g per day for 2 days of niclosamide was given for disappearing of the clinical picture. (AU)

Prevalence of Hymenolepis nana and H. diminuta from Brown Rats (Rattus norvegicus) in Heilongjiang Province, China

Hymenolepis nana and Hymenolepis diminuta are globally widespread zoonotic cestodes. Rodents are the main reservoir host of these cestodes. Brown rats (Rattus norvegicus) are the best known and most common rats, and usually live wherever humans live, especially in less than desirable hygiene conditions. Due to the little information of the 2 hymenolepidid species in brown rats in China, the aim of this study was to understand the prevalence and genetic characterization of H. nana and H. diminuta in brown rats in Heilongjiang Province, China. Total 114 fecal samples were collected from brown rats in Heilongjiang Province. All the samples were subjected to morphological examinations by microscopy and genetic analysis by PCR amplification of the mitochondrial cytochrome c oxidase subunit 1 (COX1) gene and the internal transcribed spacer 2 (ITS2) region of the nuclear ribosomal RNA gene. In total, 6.1% (7/114) and 14.9% (17/114) of samples were positive for H. nana and H. diminuta, respectively. Among them, 7 and 3 H. nana isolates were successfully amplified and sequenced at the COX1 and ITS2 loci, respectively. No nucleotide variations were found among H. nana isolates at either of the 2 loci. Seventeen H. diminuta isolates produced 2 different COX1 sequences while 7 ITS2 sequences obtained were identical to each other. The present results of H. nana and H. diminuta infections in brown rats implied the risk of zoonotic transmission of hymenolepiasis in China. These molecular data will be helpful to deeply study intra-specific variations within Hymenolepis cestodes in the future.

Infección por Hymenolepis nana en una comunidad indígena del estado Bolívar, Venezuela / Hymenolepis nana infection in an indigenous community from Bolívar State, Venezuela

Introducción: la himenolepiosis es una parasitosis intestinal causada por el género Hymenolepis. De las dos especies que pueden afectar al hombre, H. nana es la más común. Su distribución es cosmopolita, pero más frecuente en regiones tropicales. Objetivos: en junio de 2014 se realizó un estudio transversal para determinar la prevalencia de himenolepiosis en habitantes de la comunidad indígena Itopoicon del estado Bolívar, Venezuela. Métodos: fueron evaluadas 136 muestras fecales procedentes de igual número de personas, mediante las técnicas de examen directo, Kato, Willis y sedimentación espontánea. Se llenó una ficha de control de cada participante con datos de identificación y clínico-epidemiológicos de interés. Resultados: un total de 118 habitantes (86,8 por ciento) resultaron parasitados. De ellos, 26 (19,1 por ciento) tenían infección por helmintos intestinales, siendo Hymenolepis nana el helminto más comúnmente diagnosticado con 19 casos (14 por ciento). De los 19 casos de himenolepiosis, 17 ocurrieron en niños y dos en adultos, siendo la diferencia estadísticamente significativa (x2= 14,26 g.l.= 7 p< 0,05). Con relación al género no se observaron diferencias estadísticamente significativas (p> 0,05). Se determinó una amplia variedad de manifestaciones clínicas (generales, toxico-alérgico o intestinales) en los habitantes con H. nana. Conclusiones: se determinó una elevada prevalencia (14 por ciento) de infección por H. nana en una comunidad indígena del estado Bolívar, Venezuela, siendo ambos géneros afectados por igual pero con un predominio en los niños menores de 10 años. La mayoría de los casos presentó sintomatología(AU)

Introduction: hymenolepiasis is an intestinal parasitic disease caused by the genus Hymenolepis. Of the two species affecting humans, H. nana is the most common. Its distribution is cosmopolitan, but more frequent in tropical regions. Objectives: a cross-sectional study was conducted in June 2014 to determine the prevalence of hymenolepiasis among dwellers from the indigenous community of Itopoicon, Bolívar State, Venezuela. Methods: evaluation was performed of 136 stool samples from an equal number of persons using the techniques known as direct examination, Kato, Willis and spontaneous sedimentation. A control card was filled in for each participant, containing identification details and data of clinical and epidemiological interest. Results: a total 118 inhabitants (86.8 percent) were positive for parasites. Of these, 26 (19.1 percent) had intestinal helminth infection, Hymenolepis nana being the most commonly diagnosed helminth with 19 cases (14 percent). Of the 19 cases of hymenolepiasis, 17 were children and 2 were adults, the difference being statistically significant (2= 14.26 g.l. = 7 p< 0.05). No statistically significant differences were found with respect to gender (p> 0.05). A wide range of clinical manifestations (general, toxic and allergic or intestinal) were found among people with H. nana. Conclusions: ahigh prevalence (14 percent) of H. nana infection was found in an indigenous community from Bolívar State in Venezuela. Both sexes are equally affected, but there is a predominance of children under 10 years of age. Most cases were symptomatic(AU)

Prevalence of ittestinal parasites among food handlers in western Iann / La prevalencia de parasitos intestinales entre los manipuladores de alimentos en el oeste de Iran

Parasitic infection is one of the problems that affect human health, especially in developing countries. In this study, all of the fast food shops, restaurants, and roast meat outlets of Khorramabad (Western Iran) and all the staff employed by them, some 210 people, were selected through a census and their stools were examined for the presence of parasites. The parasitological tests of direct wet-mount, Lugol's iodine staining, formaldehyde-ether sedimentation and Trichrome staining techniques were performed on the samples. The data was analyzed with a chi-square test and logistic regression was selected as the analytical model. The results showed 19 (9%) stool specimens were positive for different intestinal parasites. These intestinal parasites included Giardia lamblia 2.9%, Entamoeba coli 4.3%, Blastocystis sp. 1.4%, and Hymenolepis nana 0.5%. There was a significant difference between the presence of a valid health card, awareness of transmission of intestinal parasites, participation in training courses in environmental health with intestinal parasites (p < 0.05). No statistically significant difference was found between the rate of literacy and gender among patients infected with intestinal parasites (p > 0.05). To control parasitic infection in food handlers, several strategies are recommended such as stool examinations every three months, public education, application of health regulations, controlling the validity of health cards and training on parasitic infection transmission. In this regard, the findings of the present study can be used as a basis to develop preventive programs targeting food handlers because the spread of disease via them is a common problem worldwide.

Infección parasitaria es uno de los problemas de salud humana, especialmente en los países en desarrollo. En este estudio, todas las tiendas de comida rápida, restaurantes, y tiendas de carne asada en Khorramabad (oeste de Irán) y todo el personal que trabaja en ellos, incluyendo 210 personas fueron seleccionadas a través de los censos y las heces fueron examinadas para detectar la presencia de parásitos. La prueba parasitológica directa de mojado de montaje, la tinción de Lugol's yodo, sedimentación formaldehído-éter y tricrómicas técnicas de tinción se realizaron sobre las muestras. Los datos fueron analizados con la prueba de chi-cuadrado y regresión logística seleccionado como el modelo analítico. Los resultados mostraron 19 (9%) muestras de heces fueron positivos para diferentes parásitos intestinales. Los parásitos intestinales incluyen Giardia lamblia 2.9%, Entamoeba coli 4.3%, Blastocystis sp. 1.4%, Hymenolepis nana 0.5%. Hubo diferencia significativa entre la presencia de la tarjeta sanitaria válida, el conocimiento de la transmisión de los parásitos intestinales, la participación en cursos de formación en materia de salud ambiental con parásitos intestinales (p < 0.05). No hubo diferencia estadísticamente significativa entre la tasa de alfabetización y el sexo entre los pacientes infectados con parásitos intestinales (p > 0.05). Para controlar la infección parasitaria en los manipuladores de alimentos se recomiendan varias estrategias, tales como examen de heces cada tres meses, la educación pública, se aplican las normas sanitarias, el control de validez de la tarjeta sanitaria y la transmisión formación infección parasitaria. En este sentido, los resultados del presente estudio se pueden utilizar como una base para desarrollar programas de prevención dirigidos a los manipuladores de alimentos debido a la propagación de enfermedades a través de ellos es un problema común en todo el mundo.

Heavy Hymenolepis nana Infection Possibly Through Organic Foods: Report of a Case

We encountered a patient with heavy Hymenolepis nana infection. The patient was a 44-year-old Korean man who had suffered from chronic hepatitis (type B) for 15 years. A large number of H. nana adult worms were found during colonoscopy that was performed as a part of routine health screening. The parasites were scattered throughout the colon, as well as in the terminal ileum, although the patient was immunocompetent. Based on this study, colonoscopy may be helpful for diagnosis of asymptomatic H. nana infections.

Praziquantel Treatment in Trematode and Cestode Infections: An Update

Status and emerging issues in the use of praziquantel for treatment of human trematode and cestode infections are briefly reviewed. Since praziquantel was first introduced as a broadspectrum anthelmintic in 1975, innumerable articles describing its successful use in the treatment of the majority of human-infecting trematodes and cestodes have been published. The target trematode and cestode diseases include schistosomiasis, clonorchiasis and opisthorchiasis, paragonimiasis, heterophyidiasis, echinostomiasis, fasciolopsiasis, neodiplostomiasis, gymnophalloidiasis, taeniases, diphyllobothriasis, hymenolepiasis, and cysticercosis. However, Fasciola hepatica and Fasciola gigantica infections are refractory to praziquantel, for which triclabendazole, an alternative drug, is necessary. In addition, larval cestode infections, particularly hydatid disease and sparganosis, are not successfully treated by praziquantel. The precise mechanism of action of praziquantel is still poorly understood. There are also emerging problems with praziquantel treatment, which include the appearance of drug resistance in the treatment of Schistosoma mansoni and possibly Schistosoma japonicum, along with allergic or hypersensitivity reactions against praziquantel treatment. To cope with and overcome these problems, combined use of drugs, i.e., praziquantel and other newly introduced compounds such as triclabendazole, artemisinins, and tribendimidine, is being tried.

Food additives and Hymenolepis nana infection: an experimental study

The effect of sodium benzoate [SB] on the pathogenesis of Hymenolepis nana [H. nana] and its neurological manifestations was studied in the present work. One hundred and thirty five mice were classified into three groups. GI: received SB alone, GII: received SB before and after infection with H. nana and GIII: infected with H. nana. All groups were subjected to parasitological, histopathological, immunohistochemical and biochemical assays. The results revealed a significant decrease in TL-4 serum level with a significant increase in gamma amino butyric acid [GABA] and decrease in zinc brain levels in GI, while GII showed non significant increase in IL-4 level that resulted in a highly significant increase in the mean number of cysticercoids and adult worms with delayed expulsion as compared to GIII. This was reflected on histopathological and immunohistochemical changes in the brain. Also, there was a highly significant increase in GABA and decrease in zinc brain levels in GII to the degree that induced behavioral changes. This emphasizes the possible synergistic effect of SB on the neurological manifestations of H. nana and could, in part, explain the increased incidence of behavioral changes in children exposed to high doses of SB and unfortunately have H. nana infection

Epidemiología de himenolepiosis y otras parasitosis intestinales en una comunidad suburbana de Escuque, Trujillo-Venezuela / Himenolepiosis Epidemiology and other intestinal parasites in a suburban community of Escuque, Trujillo-Venezuela

Las parasitosis intestinales son enfermedades desasistidas de los países en vías de desarrollo, en comunidades sub-urbanas, rurales, marginales e indígenas, desfavorecidas por la atención médica calificada. En Venezuela se estima una prevalencia de 7 por ciento para Hymenolepis nana. El presente estudio epidemiológico de prevalencia en el sector Fray Ignacio Álvarez, Escuque-Trujillo, fue diseñado para determinar la ocurrencia las parasitosis intestinales, de Hymenolepis nana, correlacionar las variables epidemiológicas (Graffar-Méndez Castellano) con las parasitosis intestinales y evaluar la confiabilidad del método de Kato Katz, utilizando como método gold standard el Formol-Tritón-Éter (FTE), en el hallazgo de Hymenolepis nana. Se encuestaron a 319 personas y se realizaron 224 Kato Katz y 224 Formol-Tritón-Éter. Las condiciones higiénico-sanitarias y los síntomas gastrointestinales compatibles con himenolepiosis fueron frecuentes en la comunidad, pero sólo 2,2 por ciento (5/224) fueron positivos por formol-tritón-éter. El 50,2 por ciento, de los individuos encuestados se encuentran en pobreza relativa. El riesgo de prevalencia a estar infectado por cualquier parásito, se relacionó con el estrato socioeconómico IV y V (riesgo de prevalencia=11,03; 95 por ciento; P= 0,012), con el mayor índice de Graffar (riesgo de prevalencia=21,04; 95 por ciento; P= 0,000) y con la menor instrucción de la madre (riesgo de prevalencia=26,32; 95 por ciento; P=0,012). El Método Graffar-Méndez Castellano es confiable para estimar la probabilidad de los individuos de estar infectados con parasitosis intestinales; por el contrario, el método de Kato-Katz no es confiable para la determinación de Himenolepis nana ni de otros céstodes, por lo que en estudios de prevalencia de parasitosis intestinales debe emplearse otras técnicas coprológicas de concentración

The intestinal parasitosis are neglected diseases of developing countries in sub-urban, rural, indigenous and marginalized communities, disadvantaged by qualified medical care. In Venezuela is estimated a 7 percent of prevalence for Hymenolepis nana. This epidemiological study of prevalence in the Fray Ignacio Alvarez sector, Escuque-Trujillo, was designed to determine the occurrence of intestinal parasitosis, of Hymenolepis nana, correlate epidemiological variables (Graffar Mendez Castellanos) with the I intestinal parasitosis and assess the reliability Kato Katz method, using as the gold standard method Formol-Triton-ether, in finding Hymenolepis nana. It were surveyed 319 people and conducted 224 Kato Katz and 224 Formol-Triton-ether. The sanitary-hygienic conditions and gastrointestinal symptoms consistent with himenolepiosis were common in the community, but only 2.2 percent (5 / 224) were positive for Formol-Triton-ether. The 50.2 percent of individuals surveyed were in relative poverty. The prevalence of risk to be infected by any parasite was related to IV and V socioeconomic status (prevalence of risk = 11.03, 95 percent, P = 0.012), with the highest rate of Graffar (prevalence of risk = 21.04, 95 percent, P = 0.000) and with the least education of the mother (prevalence of risk = 26.32, 95 percent, P = 0012). The Graffar Méndez Castellanos method is reliable to estimate the probability of being infected individuals with intestinal parasitosis; by contrast, Kato-Katz method is unreliable for determining neither Himenolepis nana nor other Cestoda and consequently for prevalence studies of intestinal parasite diseases must be employed other coprology concentration techniques

Hymenolepis diminuta in a child from rural area.

We report a rare case of Hymenolepis diminuta infection in a 12-year-old girl from a rural area of Devghar.

Evaluation of enzyme-linked immunosorbaent assay, using somatic and excretory-secretory antigens of strongyloides stercoralis for the serodiagnosis of strongyloidosis

Strongyloidiasis, caused by a nematode parasite so-called Strongyloides stercoralis is one of the major human intestinal nematode infections. Considering that stool examination for Strongyloides larvae is not a sensitive method and immunodiagnostic methods are more applicable for this purpose, so the present study was conducted to compare the somatic [S] and excretory - secretory [ES] antigens of Strongyloides stercoralis in IgG-ELISA to diagnose human strongyloidiasis. Serum samples obtained from 50 individuals infected with Strongyloides stercoralis. Sera from healthy control individuals, not infected with any parasitic diseases [n=/30] and from others with different parasitic infections including hydatidosis [n=20], toxocariosis [n=18], ascariasis [n=2], trichostrongylosis [n=10], and hymenolepiasis [n=2] were examined as well. The cut-off point for [S] and ES was 0.48 and 0.36, respectively. Thirty eight and 42 out of 50 individuals infected with Strongyloides stercoralis were also seropositive using [S] and ES antigens, in that order, whereas 15 cases of false positive reactions for [S] and 10 for ES antigen were detected when non-strongyloidiasis sera were examined, therefore the sensitivity of the test was 80.6% and 86.2% for [S] and ES antigens, respectively. The specificity of those antigens was calculated as 84.2% and 88.2%, correspondingly. It was concluded that overall ES antigen showed a more convincing diagnosis in comparison with [S] antigen, although every interpretation of the results should be in accompany with clinical manifestations and a history of the disease

Effect of storage on the infectivity of vampirolepis nana var. nana eggs to swiss albino mice

Vampirolepis nana is the most common cestode in humans especially children. Domestic mice and rats can serve as definitive hosts for V. nana. Confusion exists over the species status and host-specificity of this tapeworm. In a previous study done by the same authors it was found that the Egyptian human isolates of V. nana could be used to infect mice for experimental work. Eggs in human feces and in the fecal pellets excreted by mice probably lose their infectivity sooner or later. Such information is very important from the epidemiologic and epizootic points of view. The aim of this work was to study the infectivity of V. nana var. nana eggs isolated from human feces, murine fecal pellets and worm gravid proglottids after storage for different periods of time. According to the results, the transmission potential capacity of the human strain of V. nana by mice can not be ignored. The relative infectivity of the eggs isolated from the murine rectal fecal pellets is higher than that isolated from the worm because some immature eggs are found in the gravid segments. It was clear that storage of eggs had a deteriorating effect and that the egg infectivity was dependent upon storage time. After 2 wk of storage in dechlorinated water some eggs were still viable and infective. Such a group of eggs present a health risk for people living in the wastewater-exposed areas like Egyptian rural areas, or when wastewater is reused for agricultural purposes as in countries with water scarcity

Intestinal helminthic infestation in children.

In this study of fecal samples from 1000 children below 6 years of age, 680 (68.0%) detected to have intestinal helminthic infection. The incidence of intestinal helminthiasis in urban group of children was 56.8% (284 out of 500 tested) while in rural group of children was 79.2% (396 out of 500 tested). Both in rural and urban population Ascaris lumbricoides was the single predominant species, whereas a combination of A. lumbricoides and Trichuris trichiura was common multiple infection. All cultures of fecal samples positive for hook worm ova revealed the prevalent species as Necator americanus in this area.

Incidence of intestinal parasitic infection in Tajik Tribe, a Central Asian Settled in Quetta, Pakistan

445 faecal samples, collected from Tajik tribe, were processed and examined for intestinal parasites. The parasites found were Entamoeba coli 28.31%, E. histolytica 12.58%, lodamoeba butschlii 1.12%, Giardia lamblia 12.13%, Chilomastix mesnili 0.6%, Hymenolepis nana 7.86%, H. diminuta 0.22%, Taenia saginata 1.12%, Ascaris lumbricoides 4.27%, Enterobius vermicularis 2.02% and Ancylostoma duodenale 0.45%. Epidemiological factors are also discussed

Diagnóstico e tratamento de parasitoses intestinais / Diagnosis and treatment of intestinal parasitosis

Säo revistas as principais técnicas utilizadas para o diagnóstico laboratorial de rotina das parasitoses intestinais prevalentes em nosso meio, bem como os esquemas terapêuticos habitualmente empregados.