Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Echinococcus multilocularis”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 271 records · Page 15Linked to original sources
PubMed1990

Complete life cycle of the canid tapeworm, Echinococcus multilocularis, in laboratory rodents.

Mongolian gerbils, Meriones unguiculatus, when treated at intervals of 2-6 days with prednisolone tertiary butyl acetate, sustained infection with adult Echinococcus multilocularis in the small intestine, with the tapeworm exhibiting normal strobilation and egg production as in the natural canid host. Host age is critical for the survival of the tapeworm in normal gerbils; parasites survive for only 2 days in 20-wk-old animals, 4 days in 4-wk-old animals, but at least 7 days in 3-wk-old animals. The host age dependence in parasite recovery between days 28-37 postinfection was not affected by treatment from around the day of infection. Starting the treatment before infection (on day -17 relative to infection) remarkably improved the tapeworm's survival within the intestine of older animals. Eggs produced in this rodent model system 28 days postinfection were infective to rodents such as Mongolian gerbils and gray red-backed voles, Clethrionomys rufocanus bedfordiae, by oral or intraperitoneal inoculation. The E. multilocularis/Mongolian gerbil system can replace the natural canid hosts as a new way to obtain infective eggs and to analyze host-parasite interactions. The development of an alternative definitive host for zoonotic tapeworms may accelerate experimentation in this field.

Aging↗
PubMed2003

The Echinococcus multilocularis 14-3-3 protein protects mice against primary but not secondary alveolar echinococcosis.

Alveolar echinococcosis (AE), caused by the larval stage (metacestode) of the tapeworm Echinococcus multilocularis, exhibits very similar disease characteristics in humans and rodents. Recently, it has been shown that an over-expression of the parasite 14-3-3 protein could be associated to the proliferative growth of the E. multilocularis metacestode. We now demonstrate the expression of this protein at the E. multilocularis oncospheral stage as well. A recombinant E. multilocularis 14-3-3 protein (E14t) was used to vaccinate mice against either primary or secondary experimental E. multilocularis infection in BALB/c mice. Conversely to non-vaccinated but control infected mice, which developed a very weak anti-E14t response during infection, the response elicited in the E14t-vaccinated and subsequently infected animals exhibited a strong reactivity against the parasite 14-3-3 protein. Major differences became apparent between secondarily and primarily infected animals: whereas no protection against secondary infection was achieved by vaccination, vaccinated animals were protected by 97% against challenge primary infection with 2000 E. multilocularis eggs. Consequently, the parasite 14-3-3 molecule appears crucially involved in the early stage of the host-parasite interplay and exhibits potential to be used as target molecule for the development of protective tools against AE.

14-3-3 Proteins↗
PubMed2003

Perspective on control options for Echinococcus multilocularis with particular reference to Japan.

Following a brief introduction of recent advances in molecular and immunological technology for detection of persons and animals infected with Echinococcus multilocularis and an overview of the current situation of alveolar echinococcosis (AE) in Japan, perspectives on control options are discussed with reference to different epidemiological situations. AE is considered the most serious parasitic zoonosis in temperate and arctic regions of the northern hemisphere. The number of human cases differs drastically among regions. While high numbers of patients are apparently associated with high E. multilocularis prevalence in domestic dogs, e.g. in parts of Alaska and western China, the number of cases is moderate or low in areas where the parasite is mainly transmitted by wild canid species (e.g. in central Europe or temperate North America). However, the severity of the disease, the absence of curative treatment for most cases, the high cost of long-term chemotherapy and the anxiety caused for the population in highly endemic areas call for the development of preventive strategies even in regions where human AE is rare. Furthermore, in view of (1) drastically increasing numbers and infection rates of foxes involved in transmission of E. multilocularis, and (2) increasingly close contact between humans and foxes e.g. in Europe and Japan, there is considerable concern that AE incidences may in future increase in these regions. Control options depend on a variety of factors including the species of canid principally responsible for transmission and the socio-economic situation in the region. Where domestic dogs (stray or owned) are the principal hosts for E. multilocularis, control options can include those applicable to E. granulosus, i.e. reduction of the number of stray dogs, registration and regular preventive chemotherapy of owned dogs, and information campaigns for the population promoting low-risk behaviour for man and dogs. Where E. multilocularis is mainly transmitted by wild canids, the situation is far more difficult with preventive strategies still being in trial stage. Integrated control measures could include prevention information campaigns, restricting access of pet animals (dogs and cats) to rodents, chemotherapy of foxes on local or regional scales, and strategies to minimize contacts between people and foxes.

Animals↗
PubMed1997

Chemotherapy with praziquantel has the potential to reduce the prevalence of Echinococcus multilocularis in wild foxes (Vulpes vulpes).

In order to evaluate the applicability of anthelminthic treatment of wild foxes (Vulpes vulpes) to limit their infection with Echinococcus multilocularis, bait pellets, each containing 50 mg praziquantel, were repeatedly distributed in an area of 566 km2 where many foxes are infected, in southern Germany. After six baiting campaigns (15-20 baits/km2) over a period of 14 months, the prevalence of the cestode in foxes, initially 32%, had fallen to 4%. The effect was most pronounced in the central part of the treated area, where no positive fox was found in the 2 months before the end of the trial. The study was controlled for other factors that could influence the parasite's prevalence, such as the availability of intermediate hosts. While the potential of this baiting method to remove E. multilocularis from wild hosts has been demonstrated, the question of its long-term efficacy and other unresolved problems have to be addressed by consecutive studies before routine application can be recommended.

Animals↗
PubMed1981

Efficacy of praziquantel against immature Echinococcus multilocularis in dogs and cats.

Efficacy of an injectable formulation of praziquantel (given IM at a dosage of 5 mg/kg of body weight) against immature Echinococcus multilocularis was studied in 18 experimentally infected dogs and 22 experimentally infected cats. There were no worms recovered at necropsy from any of the treated hosts. However, whereas E multilocularis worms were recovered from all nontreated control dogs (n = 9; min-max 15-1,840, mean 483), such tapeworms were recovered from only k6 of the 11 nontreated control cats (min-max 2-820; overall mean 123.4). The study demonstrates 100% clearance of E multilocularis by praziquantel in experimentally infected dogs and cats, and shows that cats are not as suitable as experimental hosts for this parasite as are dogs.

Animals↗
PubMed2003

Echinococcus multilocularis: secondary poisoning of fox population during a vole outbreak reduces environmental contamination in a high endemicity area.

This paper describes the role of fox population level on Echinococcus multilocularis infection in foxes in a highly endemic area in eastern France. Fox population level was monitored by spotlight survey at Le Souillot from 1989 to 2000, and from 1992 to 2000 at Chemin, a control site located in a low endemic area. The infection level of the fox population was estimated at Le Souillot from winter 1995 to winter 1999 using a coproantigen ELISA performed on faeces collected in the field. Population biomass of intermediate hosts (Microtus arvalis and Arvicola terrestris) was monitored using index methods from 1995 to 1999. At Le Souillot, a significant decline in the fox population level was recorded after spring 1997 (P<0.001), and the population level remained low until 2000. The decline occurred when 31% of the grassland area was treated with bromadiolone, an anticoagulant used at a large scale for the control of A. terrestris population outbreaks. No decline of population was recorded at Chemin, where bromadiolone was not used for rodent control. Significant differences among ELISA OD distributions in fox faeces were recorded for the five winters under study at Le Souillot (P=0.0004). The median of ELISA OD distribution was 0.209 and 0.207 before the population decline (winter 1995 and 1996, respectively), significantly increased to 0.306 just after the decline (winter 1997), and then significantly decreased to 0.099 and 0.104 afterwards (winter 1998 and 1999, respectively). Therefore, the decrease in infection level occurred during winter 1998, 1 year after the population decline, when the intermediate host biomass in the field was at its highest. These results suggest a complex dependence between the fox population level and E. multilocularis infection in a high endemicity area. Alternative ways to control fox population as a way to reduce E. multilocularis transmission in a given area are discussed.

4-Hydroxycoumarins↗
PubMed1987

A comparative study of UTP-D-glucose-1-phosphate uridylyl transferase in the cysts of Echinococcus multilocularis and the livers of infected and control Meriones unguiculatus.

Kinetic and physical parameters of UDP-glucose pyrophosphorylase were determined in Meriones unguiculatus infected with Echinococcus multilocularis metacestodes (cestoda). Studies were carried out on parasite cysts, and on livers from control and infected animals after purification of the enzyme by affinity chromatography on UTP-agarose. The enzyme from infected and control livers had km values for UTP of 0.01 mM and 0.5 mM, respectively; for glucose-1-phosphate values were 0.46 mM and 0.07 mM, respectively. On the other hand the enzyme from cysts was found to have a higher Km for UTP (1 mM) and for glucose-1-phosphate (1.5 mM) than from infected or non-infected livers. Physical characteristics (pI = 6 and Mr = 160,000) of UDP-glucopyrophosphorylases were the same in controls and infected host livers but were different from the cyst enzyme (pI = 7 and Mr = 251,000). These results provide evidence for the existence of significant differences between parasitic and host enzymes, which could possibly be exploited in chemotherapy.

Animals↗
PubMed2000

Dose dependency of prednisolone on the establishment of Echinococcus multilocularis infection in an alternative definitive host, Mongolian gerbil.

This study revealed the dose dependency of prednisolone tertiary-butylacetate (PTBA) treatment on the establishment of Echinococcus multilocularis in the small intestine of Mongolian gerbil (Meriones unguiculatus) and that some of the physiological parameters of host were correlated with the doses of PTBA and establishment of the worm. Twenty Mongolian gerbils were divided into 5 groups, according to the doses of PTBA; 0 mg, 0.5 mg, 2 mg, 5 mg and 10 mg per head. All animals were injected intraperitoneally with PTBA every other day from 6 days before to 6 days after infection. Doses of PTBA and the number of worms recovered at 7 days post-infection showed a positive correlation (r = 0.929, P < 0.0001). The increase of total protein (TP) and the decrease of the percentage of lymphocytes in the peripheral leukocytes were dependent on doses of PTBA (TP: r = 0.811, P < 0.0001, percentage of lymphocyte: r = -0.92, P < 0.0001). The TP and the percentage of lymphocyte also correlated with the number of worms recovered (TP: r = 0.617, P = 0.0049; percentage of lymphocyte: r = -0.800, P < 0.0001).

Animals↗
PubMed1997

Antibodies against Echinococcus multilocularis alkaline phosphatase as markers for the specific diagnosis and the serological monitoring of alveolar echinococcosis.

The immunological properties of the purified alkaline phosphatase (pAP) of Echinococcus multilocularis metacestodes have been investigated using alveolar echinococcosis (AE) patient sera in ELISA tests. A comparative study was done with EmC-Ag (crude antigen) and pAP-Ag (purified antigen). When the parasite purified enzyme pAP was used as antigen, the specificity of the ELISA was markedly increased since it reached 100% without any decrease of its sensitivity (100%). The serologic follow-up of AE patients was conducted during several months with these two antigens in three categories of patients: cured, stabilized and aggravated. There was a good correlation between clinical and serologic data when the pAP was used as antigen in ELISA tests. The anti-pAP antibodies titres did change more rapidly than anti-EmC antibodies titres when a recurrence occurred. Modifications of the anti-pAP antibodies levels were also observed during the patient's therapy: mebendazole, albendazole and Isoprinosine. These results suggest that pAP-Ag should be used for the diagnosis and the follow-up of AE patients.

Alkaline Phosphatase↗
PubMed1999

Echinococcus multilocularis coproantigen detection by enzyme-linked immunosorbent assay in fox, dog, and cat populations.

A sandwich enzyme-linked immunosorbent assay (ELISA) for the detection of Echinococcus multilocularis coproantigens (EM-ELISA) was developed with polyclonal rabbit (solid phase) and chicken egg (catching) antibodies that were directed against E. multilocularis coproantigens and somatic worm antigens, respectively. In experimentally infected dogs and cats, coproantigens were first detectable 6-17 days postinfection (PI) in samples of 8 dogs (worm burdens at necropsy: 6,330-43,200) and from 11 days PI onward in samples of 5 cats infected with 20-6,833 worms. After anthelmintic treatment of 4 dogs and 5 cats at day 20 PI, coproantigen excretion disappeared within 3-5 days. The sensitivity of the ELISA was 83.6% in 55 foxes infected with 4-60,000 E. multilocularis, but reached 93.3% in the 45 foxes harboring more than 20 worms. The EM-ELISA was used in surveys of "normal" dog and cat populations in Switzerland. Among 660 dogs and 263 cats, 5 dogs and 2 cats exhibited a positive reaction. In 2 of these dogs (0.30%) and 1 cat (0.38%), intestinal E. multilocularis infections were confirmed by necropsy, polymerase chain reaction PCR, or both. The specificites of the ELISA in these groups were found to be 99.5% and 99.6%, respectively, if positive ELISA results that could not be confirmed by other methods were classified as "false positive" reactions.

Animals↗
PubMed1988

Risk factors for infection with Echinococcus multilocularis in Alaska.

We studied 19 Eskimo patients with alveolar hydatid disease from the north-western coast of Alaska for risk factors for infection with Echinococcus multilocularis. Each case-patient was matched by age and sex with 2 unrelated controls who had no clinical or serologic evidence of infection with E. multilocularis and who resided in three villages endemic for alveolar hydatid disease. Behaviors thought to increase exposure to E. multilocularis and the chronologic occurrence of these behaviors in the participant's life were assessed by a standardized questionnaire. Case-patients were more likely than controls to have owned dogs for their entire lives (odds ratio 6.00, P less than 0.05), tethered their dogs near the house (odds ratio 8.50, P less than 0.05), and lived in houses built directly on the tundra rather than on gravel or a permanent foundation (odds ratio 11.00, P less than 0.01). Case-patients were not more likely to have owned sled dogs, trapped or skinned foxes, or engaged in other outdoor activities away from home. These findings suggest that controlling the parasite in the domestic dog population, as well as controlling the dog population itself, are important aspects of preventing alveolar hydatid disease in the northwestern Native Alaskan population.

Adolescent↗
PubMed1983

Serologic tests for diagnosis and post-treatment evaluation of patients with alveolar hydatid disease (Echinococcus multilocularis).

The indirect hemagglutination (IHA) and immunoelectrophoresis (IEP) tests were used for diagnosis and follow-up evaluation of 17 patients with alveolar hydatid disease caused by Echinococcus multilocularis. Follow-up periods ranged from 2 to 22 years. At the time of diagnosis 16 (94%) patients' sera gave IHA titers greater than or equal to 1:128. Serum specimens from 13 patients were examined by IEP; nine (69%) revealed the arc 5, and three of the four arc 5-negative sera revealed one or more non-characterized bands. Titers declined markedly during the first year following radical surgical resection of the larval lesions; in three cases clinical evidence of recurrence was preceded by rising serologic titers. Antibody has persisted at high levels in non-resected patients treated continuously with high doses of mebendazole.

Adolescent↗
PubMed1991

Specific cellular and humoral immune responses in patients with different long-term courses of alveolar echinococcosis (infection with Echinococcus multilocularis).

Alveolar echinococcosis is a serious and often fatal disease of humans that in most cases can be efficiently cured only by complete surgical resection of the Echinococcus multilocularis lesion. In a few patients, however, a spontaneous cure of the disease has been observed by demonstrating the presence of lesions with dead metacestodes. The present study shows a comparative analysis of the cellular (lymphoproliferative assay) and humoral (antibody activity in an Em2 enzyme-linked immunosorbent assay [ELISA] and immunoblotting) immune response in 1) patients who were cured by a radical surgical resection of the E. multilocularis parasite lesion, 2) patients who had a partial surgical resection of the parasite lesion, 3) patients who had a non-resectable alveolar echinococcosis, and 4) patients who were shown to be spontaneously cured and had lesions with dead parasites. The in vitro lymphoproliferative response to E. multilocularis antigen stimulation was very high in cured patients who had radical surgery or in patients with lesions containing dead parasites, but it was significantly lower in patients who had partial surgical or no resection. Antibody concentrations in the Em2-ELISA were high in patients who had incomplete or no surgery, and low or negative in cured patients who had radical surgery or in patients with lesions containing dead parasites. Immunoblot analysis of patient sera revealed a consistent antibody banding pattern among cured patients with radical surgery and patients with incomplete or no surgery, whereas cured patients with lesions containing dead parasites showed a very faint antibody pattern.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Echinococcus multilocularis metacestodes: biochemical and ultrastructural investigations on the effect of isatin (2-3 indoline dione) in vivo.

A study on the biochemical and ultrastructural effects of isatin on Echinococcus multilocularis metacestodes in Meriones unguiculatus is reported. In the metacestode, after an 18 day treatment period, the alkaline phosphatase and lactate dehydrogenase activities decreased and the acid phosphatase activity increased. Glucose and glycogen stores declined significantly. Examinations of the ultrastructure revealed an increase of lysosomes and phagocytic reactions. The protoscolesces were damaged and an abnormal striated process appeared. The tegumental cytoplasmic syncytium remained unaltered. These observations suggest that isatin derivatives may have a role in the chemotherapy of infections caused by Echinococcus spp.

Acid Phosphatase↗
PubMed1998

Monitoring of Echinococcus multilocularis infection in red foxes in Shiretoko, Japan, by coproantigen detection.

The study was conducted to evaluate a mAb-based coproantigen detection assay for monitoring fox prevalence of Echinococcus multilocularis infections in the Shiretoko National Park in Hokkaido, Japan. Eight fox families, each consisting of 2-4 adults and their pups, were selected because their territories have been determined. Faeces of each family (total n = 537) were collected monthly from April to October, 1994. Detection of coproantigen and taeniid eggs was recognized in 58 and 27 faeces, respectively, but mostly restricted in 1 family, in which coproantigen ELISA OD values had dual peaks, one in June and the other in October, whereas taeniid eggs were detected only from April to July. Fox pup faeces (n = 51) collected around the dens used by the positive family were all coproantigen and taeniid egg negative except for 1 faeces. These results suggest that the prevalence and infection pressure in the study area were low and the infected family terminated the infection in the summer and acquired a new one in the early autumn, 1994. This monitoring method for fox infection will be a practical management tool for E. multilocularis infection, especially at the tourist spots in Hokkaido where close contact of fox with humans is frequently observed.

Animals↗
PubMed1979

Protection of cotton rats against experimental Echinococcus multilocularis infections with BCG cell walls.

Previous works has indicated that cotton rats treated with Mycobacterium bovis strain BCG are effectively protected against an infection with the metastatically proliferating metacestodes of Echinococcus multilocularis. In an attempt to induce a similar protection in the absence of tubercular granulomatous lesions, cotton rats were treated with BCG cell walls. A single injection of 150 micrograms of cell walls, emulsified in mineral oil-Tween-saline, 2 weeks before the inoculation of the parasite completely protected the animals against infection with E. multilocularis. This protection was correlated with an increase in the numbers of monocytes and, as judged by acid phosphatase activity, an activation of these cells. This study shows that BCG cell walls are as effective in protecting animals against E. multilocularis as the viable organism.

Animals↗
PubMedDate not supplied

[The occurrence of Echinococcus multilocularis in red foxes in lower Saxony: identification of a high risk area by spatial epidemiological cluster analysis].

There is considerable interest in the spatial distribution of Echinococcus multilocularis in red foxes (Vulpes vulpes L.), because this parasite causes the zoonoses of alveolar echinococcosis which is potentially of high fatality rate. High risk areas are known from France, Switzerland and the Swabian Alb in Germany for a long time. In this work, the spatial scan statistic is introduced as an instrument for identification and localisation of high risk areas, so called disease clusters in spatial epidemiology. The use of the spatial scan statistic along with data about the distribution of the parasite in 5365 red foxes in Lower Saxony, that were collected during 1991 to 1997, led to the identification of another high risk area. The relative risk for this disease cluster is approximated by RR = 5.03 (CI0.95(RR) = [4.27; 6.58]) for the period of 1991 to 1994 and by RR = 4.45 (CI0.95(RR) = [3.53; 5.59]) for the period of 1994 to 1997, respectively.

Animals↗
PubMed2004

Wilderness in the city: the urbanization of Echinococcus multilocularis.

A distinct increase in fox populations, particularly in urban areas, has been observed in Europe. This is of particular concern in endemic regions of the small fox tapeworm Echinococcus multilocularis, the aetiological agent of human alveolar echinococcosis. Novel tools have facilitated the investigation of the ecology of urban foxes and have demonstrated the urban wildlife cycle of E. multilocularis. Such studies are essential for estimating the risk of transmission to humans and to determine the basics for the development of control strategies.

Animals↗