Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 48
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Parasitol Res ; 115(6): 2485-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26987642

RESUMO

Fresh fruit, vegetables, mushrooms, and other fresh produce are recognised as important vehicles of infection for several foodborne parasites, particularly those with a faecal-oral transmission route and robust environmental transmission stages. Nevertheless, analysis of such foods for parasite transmission stages, even during outbreaks, tends to show only low contamination. Echinococcus multilocularis is considered one of the most important foodborne parasites, but there are few studies in which fresh produce or like foods collected in their natural habitat is analysed for contamination with E. multilocularis eggs. In this article, we question a recent study from Poland reporting over 23 % of fresh berries, vegetables, and mushroom being highly contaminated with E. multilocularis eggs. In particular, it appears unlikely that 20 % of raspberries, which are elevated from ground level, should be exposed to faecal contamination. Additionally, the similar egg contamination of vegetation in forest and plantation environments is surprising considering the preference of the parasite's most competent intermediate hosts for the latter environment. Furthermore, a lack of specific temporal information is concerning due to the varying infection pressure (and therefore environmental contamination) occurring in definitive hosts over the course of the year. Several important aspects of the study seem to us to have been neglected, and we are concerned that the published data might, if not questioned, lead to incorrect interpretation, and unnecessary losses in the agricultural sector.


Assuntos
Equinococose/epidemiologia , Equinococose/transmissão , Echinococcus multilocularis/isolamento & purificação , Doenças Transmitidas por Alimentos/parasitologia , Frutas/parasitologia , Verduras/parasitologia , Agaricales , Animais , Europa (Continente) , Fezes/parasitologia , Raposas/parasitologia , Polônia
2.
Parasitol Res ; 114(7): 2777-80, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25895063

RESUMO

Invertebrate models provide several important advantages over their vertebrate counterparts including fewer legislative stipulations and faster, more cost-effective experimental procedures. Furthermore, various similarities between insect and mammalian systems have been highlighted. To obtain maximum use of invertebrate models in pharmacology, their fidelity as analogues of vertebrate systems requires verification. We utilised a flour beetle (Tenebrio molitor)-tapeworm (Hymenolepis diminuta) model to evaluate the efficacy of known anthelmintic compounds, praziquantel, mebendazole and levamisole against H. diminuta cysticercoid larvae in vitro. Inhibition of cysticercoid activity during the excystation procedure was used as a proxy for worm removal. The effects of the three compounds mirrored their relative efficacy in treatment against adult worms in mammalian systems; however, further study is required to determine the fidelity of this model in relation to dose administered. The model precludes comparison of consecutive daily administration of pharmaceuticals in mammals due to cysticercoids not surviving outside of the host for multiple days. Treatment of beetles in vivo, followed by excystation of cysticercoids postdissection could potentially allow for such comparisons. Further model validation will include analysis of pharmaceutical efficacy in varying H. diminuta isolates and pharmaceutical dilution in solvents other than water. Notwithstanding, our results demonstrate that this model holds promise as a method to efficiently identify promising new cestocidal candidates.


Assuntos
Anti-Helmínticos/administração & dosagem , Cestoides/efeitos dos fármacos , Infecções por Cestoides/tratamento farmacológico , Besouros/parasitologia , Praziquantel/administração & dosagem , Animais , Cestoides/parasitologia , Infecções por Cestoides/parasitologia , Besouros/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Humanos , Masculino
3.
Parasitol Res ; 114(7): 2705-14, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26008635

RESUMO

Eggs of the pig whipworm, Trichuris suis ova (TSO), are currently tested in human clinical trials for their potential immunomodulatory capacity. The biological potency of TSO (egg viability and infectivity) is traditionally assessed in Göttingen minipigs as the establishment of intestinal larvae after inoculation with a known number of eggs. To minimize testing in animal models, development of an in vitro egg hatching assay is proposed as a reliable, cost-effective, and a faster alternative to test the egg viability. The present study aimed to investigate the influence of different chemical, physical, and biological factors on egg hatching. Thus, in a series of experiments and in different combinations, the eggs were stimulated with glass beads, artificial gastric juice, bile salt and trypsin solution, fermentation gut medium, or stimulated with mucosal scrapings from the ileum and the large intestine of the infected and uninfected Göttingen minipig. Mechanical stimulation with glass beads presented a simple and reproducible method for egg hatching. However, incubation of eggs with mucosal scrapings from the ileum, caecum, and colon for 24 h at 38 °C significantly increased hatching.


Assuntos
Óvulo/crescimento & desenvolvimento , Trichuris/crescimento & desenvolvimento , Animais , Terapia Biológica/instrumentação , Terapia Biológica/métodos , Ceco/parasitologia , Humanos , Intestino Grosso/parasitologia , Larva/crescimento & desenvolvimento , Suínos , Porco Miniatura , Fatores de Tempo
4.
J Crohns Colitis ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899778

RESUMO

BACKGROUND AND AIMS: To demonstrate that administration of 7500 Trichuris suis ova every second week over 24 weeks would reduce the intestinal inflammation in moderate ulcerative colitis. METHODS: A single-centre, randomized, double-blinded, placebo-controlled, phase 2b clinical trial of 7500 Trichuris suis ova every two weeks for 24 weeks compared to placebo in moderate activity of ulcerative colitis (Mayo score 6-10) were performed. Primary outcome: Clinical remission. Secondary outcomes: Clinical response at 24 weeks, complete corticosteroid-free clinical remission, endoscopic remission, symptomatic remission at 12 and 24 weeks and partial Mayo score over time. RESULTS: 119 patients were randomized to Trichuris suis ova (n=60) and placebo (n=59). At week 24, clinical remission was achieved in 30% of Trichuris suis ova-treated vs. 34% of placebo-treated (RR=0.89; CI:0.52-1.50; p=0.80, ITT). No difference was found in clinical response in any of the clinical response subgroups. However, in patients who did not need treatment with corticosteroids during the trial, a temporary effect of TSO was seen in the analysis of symptomatic remission of week 12 (p=0.01), and the partial Mayo score at week 14 and week 18 (p<0.05 and p=0.02). CONCLUSIONS: Compared to placebo, Trichuris suis ova was not superior in achieving clinical remission at week 24 in ulcerative colitis or in achieving clinical Mayo score reduction, complete corticosteroid-free clinical remission or endoscopic remission. However, Trichuris suis ova treatment induced symptomatic temporary remission at week 12.

5.
Malar J ; 10: 75, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21457533

RESUMO

BACKGROUND: Sulphadoxine-pyrimethamine (SP) and chloroquine (CQ) have been used in treatment of falciparum and vivax malaria in Nepal. Recently, resistance to both drugs have necessitated a change towards artemisinin combination therapy (ACT) against Plasmodium falciparum in highly endemic areas. However, SP is still used against P. falciparum infections in low endemic areas while CQ is used in suspected cases in areas with lack of diagnostic facilities. This study examines the prevalence of molecular markers of CQ and SP resistance in P. falciparum and Plasmodium vivax to determine if high levels of in vivo resistance are reflected at molecular level as well. METHODS: Finger prick blood samples (n=189) were collected from malaria positive patients from two high endemic districts and analysed for single nucleotide polymorphisms (SNPs) in the resistance related genes of P. falciparum and P. vivax for CQ (Pfcrt, Pfmdr1, Pvmdr1) and SP (Pfdhfr, Pfdhps, Pvdhfr), using various PCR-based methods. RESULTS AND DISCUSSION: Positive P. vivax and P. falciparum infections were identified by PCR in 92 and 41 samples respectively. However, some of these were negative in subsequent PCRs. Based on a few P. falciparum samples, the molecular level of CQ resistance in P. falciparum was high since nearly all parasites had the Pfcrt mutant haplotypes CVIET (55%) or SVMNT (42%), though frequency of the Pfmdr1 wild type haplotype was relatively low (35%). Molecular level of SP resistance in P. falciparum was found to be high. The most prevalent Pfdhfr haplotype was double mutant CNRNI (91%), while frequency of Pfdhps double mutant SGEAA and AGEAA were 38% and 33% respectively. Combined, the frequency of quadruple mutations (CNRNI-SGEAA/AGEAA) was 63%. Based on P. vivax samples, low CQ and SP resistance were most likely due to low prevalence of Pvmdr1 Y976F mutation (5%) and absence of triple/quadruple mutations in Pvdhfr. CONCLUSIONS: Based on the limited number of samples, prevalence of CQ and SP resistance at molecular levels in the population in the study area were determined as high in P. falciparum and low in P. vivax. Therefore, CQ could still be used in the treatment of P. vivax infections, but this remains to be tested in vivo while the change to ACT for P. falciparum seems justified.


Assuntos
Antimaláricos/farmacologia , Resistência a Medicamentos , Malária Falciparum/tratamento farmacológico , Malária Vivax/tratamento farmacológico , Plasmodium falciparum/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Polimorfismo de Nucleotídeo Único , Proteínas de Protozoários/genética , Antimaláricos/uso terapêutico , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Combinação de Medicamentos , Humanos , Malária Falciparum/genética , Malária Falciparum/parasitologia , Malária Vivax/genética , Malária Vivax/parasitologia , Nepal , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Plasmodium vivax/efeitos dos fármacos , Plasmodium vivax/genética , Reação em Cadeia da Polimerase , Pirimetamina/farmacologia , Pirimetamina/uso terapêutico , Sulfadoxina/farmacologia , Sulfadoxina/uso terapêutico
6.
Parasitol Res ; 109(5): 1293-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21541754

RESUMO

The genus Taenia includes several species of veterinary and public health importance, but diagnosis of the etiological agent in definitive and intermediate hosts often relies on labor intensive and few specific morphometric criteria, especially in immature worms and underdeveloped metacestodes. In the present study, a multiplex PCR, based on five primers targeting the 18S rDNA and ITS2 sequences, produced a species-specific banding patterns for a range of Taenia spp. Species typing by the multiplex PCR was compared to morphological identification and sequencing of cox1 and/or 12S rDNA genes. As compared to sequencing, the multiplex PCR identified 31 of 32 Taenia metacestodes from rodents, whereas only 14 cysts were specifically identified by morphology. Likewise, the multiplex PCR identified 108 of 130 adult worms, while only 57 were identified to species by morphology. The tested multiplex PCR system may potentially be used for studies of Taenia spp. transmitted between rodents and carnivores.


Assuntos
Carnívoros/parasitologia , Reação em Cadeia da Polimerase Multiplex/métodos , Parasitologia/métodos , Roedores/parasitologia , Taenia/classificação , Taenia/isolamento & purificação , Teníase/veterinária , Animais , Primers do DNA/genética , DNA de Helmintos/genética , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , RNA Ribossômico/genética , RNA Ribossômico 18S/genética , Taenia/genética , Teníase/parasitologia
7.
Vet Med Sci ; 7(6): 2290-2302, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34390537

RESUMO

The present study aimed to estimate the prevalence of zoonotic pathogens Giardia duodenalis, Cryptosporidium spp., Toxoplasma gondii and Erysipelothrix in muskoxen (Ovibos moschatus) and sheep (Ovis aries) from Greenland. In 2017 and 2018, faecal samples were collected from wild muskoxen from three distinct populations (Zackenberg, Kangerlussuaq, and Ivittuut) and from domestic sheep from southwest Greenland. Blood samples were collected from muskoxen from Kangerlussuaq and Ivittuut and from sheep. Faecal samples were tested for specific DNA of G. duodenalis and Cryptosporidium spp., and blood samples were tested for antibodies against T. gondii and Erysipelothrix. The estimated prevalence of G. duodenalis was 0% (0/58), 17% (7/41) and 0% (0/55) in muskoxen from Zackenberg, Kangerlussuaq and Ivittuut, respectively, and 37% (16/43) in sheep. The estimated prevalence of Cryptosporidium was 0% (0/58), 2% (1/41), 7% (4/55) in muskoxen from Zackenberg, Kangerlussuaq, Ivittuut, respectively, and 2% (1/43) in sheep. Neither Giardia nor Cryptosporidium were detected in winter samples (0/78). Of the positive samples, Giardia from one muskox sample only was successfully typed as G. duodenalis assemblage A, and Cryptosporidium from two muskoxen was successfully typed as C. parvum, subtype IIdA20G1e. The estimated T. gondii seroprevalence was 2% (1/44) and 0% (0/8) in muskoxen from Kangerlussuaq and Ivittuut, respectively, and 1% (1/155) in sheep. The estimated Erysipelothrix seroprevalence was 2% (1/45) and 13% (1/8) in muskoxen from Kangerlussuaq and Ivittuut, respectively, and 7% (10/150) in sheep. The results of this study add to the scarce knowledge on zoonotic pathogens in the Arctic.


Assuntos
Criptosporidiose , Cryptosporidium , Doenças dos Ovinos , Animais , Criptosporidiose/epidemiologia , Cryptosporidium/genética , Groenlândia , Estudos Soroepidemiológicos , Ovinos , Doenças dos Ovinos/epidemiologia , Carneiro Doméstico
8.
Pathogens ; 10(11)2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34832667

RESUMO

Dogs infected with the cardiopulmonary nematode Angiostrongylus vasorum may suffer from respiratory distress and/or bleeding disorders. Descriptions of clinical signs in foxes are rare, despite high prevalence. To evaluate the impact of infection on coagulation and immune response, serum proteins from eight experimentally infected foxes before and after inoculation (day 0, 35, 84, 154) were subjected to differential proteomic analyses based on quantitative data and compared to available data from dogs. The number of proteins with differential abundance compared to the uninfected baseline increased with chronicity of infection. Bone marrow proteoglycan, chitinase 3-like protein 1 and pulmonary surfactant-associated protein B were among the most prominently increased proteins. The abundance of several proteins involved in coagulation was decreased. Enriched pathways obtained from both increased and decreased proteins included, among others, "platelet degranulation" and "haemostasis", and indicated both activation and suppression of coagulation. Qualitative comparison to dog data suggests some parallel serum proteomic alterations. The comparison, however, also indicates that foxes have a more adequate immunopathological response to A. vasorum infection compared to dogs, facilitating persistent infections in foxes. Our findings imply that foxes may be more tolerant to A. vasorum infection, as compared to dogs, reflecting a longer evolutionary host-parasite adaptation in foxes, which constitute a key wildlife reservoir.

9.
Parasitol Res ; 107(1): 147-51, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20369254

RESUMO

Experimental infection with Angiostrongylus vasorum was conducted in Iberian slugs Arion lusitanicus. Initially, different size/age groups of juvenile slugs (small, <0.5 g and medium, 0.5-1 g) were exposed to freshly isolated first-stage parasitic larvae (L1) of A. vasorum. The slugs were subsequently incubated at 5, 10 and 15 degrees C for 6 weeks. Larval development within the slugs differed significantly with temperature. At 15 degrees C, all larvae developed into the third larval stage (L3), at 10 degrees C into the second stage (L2), whereas no development was observed at 5 degrees C. The mean larval burdens were highest in the largest group of slugs and tended to increase with higher temperature. In a second experiment isolated L1 were incubated at 5, 10 and 15 degrees C for 3 and 7 days prior to infection of slugs, which then were kept for 6 weeks at 15 degrees C. The infectivity decreased significantly with the larval storage time and the mean larval burden per slug was lower at higher incubating temperature. However, all established larvae developed into infective L3. Temperature had an effect on the development of the larvae and thus an impact on transmission of the parasite as only L3 are infective to the definitive canid hosts.


Assuntos
Angiostrongylus/crescimento & desenvolvimento , Angiostrongylus/patogenicidade , Gastrópodes/parasitologia , Temperatura , Fatores Etários , Animais , Larva/crescimento & desenvolvimento , Larva/patogenicidade
10.
Parasitol Res ; 107(1): 135-40, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20372926

RESUMO

The cardiovascular nematode Angiostrongylus vasorum is spreading in the fox and dog populations of northern Europe. A. vasorum can result in severe clinical manifestations in dogs; therefore, specific diagnosis is crucial for assessing its prevalence. In the present study, faecal samples from foxes and domestic dogs were tested by a new polymerase chain reaction (PCR) targeting the second internal transcribed region of the ribosomal DNA (ITS2) of A. vasorum. Initial isolation of faecal larvae by sieving facilitated the processing of larger sample volumes and allowed for the recovery of dead larvae from frozen samples. The sieve-PCR method enabled the identification of a single larva per 2 g of faecal sample and did not amplify DNA of a range of canine helminths, thus presenting a non-invasive tool for wildlife surveillance and for confirmative diagnosis in dogs.


Assuntos
Angiostrongylus/isolamento & purificação , Doenças do Cão/diagnóstico , Fezes/parasitologia , Raposas/parasitologia , Parasitologia/métodos , Reação em Cadeia da Polimerase/métodos , Infecções por Strongylida/veterinária , Angiostrongylus/genética , Animais , Primers do DNA/genética , DNA de Helmintos/genética , DNA Espaçador Ribossômico/genética , Doenças do Cão/parasitologia , Cães , Europa (Continente) , Sensibilidade e Especificidade , Infecções por Strongylida/parasitologia
11.
Ann Parasitol ; 66(2): 259-263, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32592563

RESUMO

Herein we describe the origin of the International Commission on Trichinellosis more than 60 years after its foundation. We attempt to clarify previous debate over the founding presidents and particularly the role of Polish parasitologist, Zbigniew Kozar. Seminal and core proceedings of the Commission published in Wiadomosci Parazytologiczne and other records were used to advance this goal. An early regional commission initially held in Budapest, Hungary at the Hungarian Meeting of Parasitologists was devoted to trichinellosis and was presided over by Kozar from 1958 to 1960. However, the official formation of the Commission did not occur until 1960 during the 1st International Conference on Trichinellosis held in Warsaw, Poland, where Witold Stefanski was elected president. During the 2nd International Conference on Trichinellosis, which was held in 1969 in Wroclaw, Poland, Samuel E. Gould was elected president until his untimely death in 1970. Zbigniew Kozar was secretary general from 1960 to 1972. Beginning with the 3rd International Conference held in Miami, Florida, USA in 1972, the activities of the Commission and the Conference became better documented.


Assuntos
Cooperação Internacional , Sociedades Médicas , Triquinelose , História do Século XX , Humanos , Sociedades Médicas/história , Sociedades Médicas/organização & administração
12.
PLoS One ; 15(1): e0227561, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31935259

RESUMO

Host-parasite interactions may be modulated by host- or parasite-associated microbes, but the role of these are often overlooked. Particularly for parasites with intestinal stages (either larval or adult), the host gut microbiome may play a key role for parasite establishment; moreover, the microbiome may change in response to invading parasites. Hypothesis testing at the organismal level may be hampered, particularly in mammalian definitive hosts, by ethical, logistical, and economical restrictions. Thus, invertebrates naturally serving as intermediate hosts to parasites with complex life cycles may inform the development of mammalian models as an early-stage host-parasite model. In addition, several important pathogens are vectored by insects, and insect gut microbiome-pathogen interactions may provide essential base-line knowledge, which may be used to control vectorborne pathogens. Here, we used the grain beetle, Tenebrio molitor, a host of the tapeworm Hymenolepis diminuta, to explore interactions between infection status and resident gut microbiota at two pre-determined time points (day two and seven) post infection. Using 16S/18S microbial profiling, we measured key parameters of the composition, relative abundance, and diversity of the host gut bacteriome and mycobiome. In addition, we quantified the systemic beetle immune response to infection by Phenoloxidase activity and hemocyte abundance. We found significant changes in the gut bacteriome and mycobiome in relation to infection status and beetle age. Thus, the relative abundance of Proteobacteria was significantly higher in the gut of infected beetles and driven mostly by an increased abundance of Acinetobacter. In addition, the mycobiome was less abundant in infected beetles but maintained higher Shannon diversity in infected compared with non-infected beetles. Beetles treated with a broad-spectrum antibiotic (Tetracycline) exhibited significantly reduced parasite establishment compared with the untreated control group, indicating that the host microbiome may greatly influence hatching of eggs and subsequent establishment of H. diminuta larvae. Our results suggest that experimental work using invertebrates may provide a platform for explorative studies of host-parasite-microbe interactions and their underlying mechanisms.


Assuntos
Besouros/parasitologia , Microbioma Gastrointestinal , Hymenolepis diminuta/fisiologia , Animais , Antibacterianos/farmacologia , Besouros/imunologia , DNA Bacteriano/isolamento & purificação , DNA Bacteriano/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Hemolinfa/metabolismo , Interações Hospedeiro-Parasita , Monofenol Mono-Oxigenase/metabolismo , Micobioma/efeitos dos fármacos , Análise de Componente Principal , Proteobactérias/genética , Proteobactérias/isolamento & purificação , Tetraciclina/farmacologia
13.
PLoS Negl Trop Dis ; 14(6): e0008382, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32569309

RESUMO

BACKGROUND: A substantial proportion of echinococcosis transmission to humans via contamination of food has been assumed. However, the relative importance of food as a transmission vehicle has previously been estimated through expert opinion rather than empirical data. OBJECTIVE: To find and evaluate empirical data that could be used to estimate the source attribution of echinococcosis, in particular the proportion that is transmitted through contaminated food. METHODS: A systematic review was undertaken to identify reports on the risk factors for human cystic (CE) and alveolar (AE) echinococcosis. Data bases searched included PubMed, Scopus, Web of Knowledge, Cab Direct, Science Direct, Google Scholar, eLIBRARY.RU, CyberLeninka, CNKI and VIP. Search terms included Echinococc*, hydatid, epidemiology, logistic regression, risk factors, odds ratio, relative risk, risk factors. Reports, including grey literature where available, that had suitable data were selected and data were extracted. The main pathways of transmission were hypothesised to be contact with the definitive host, contaminated water, contaminated food and contaminated environment (other than food). For each study the attributable fraction for these potential sources of infection was calculated from the data presented. A meta-analysis was then undertaken to obtain pooled estimates for the relative contribution of these transmission pathways. RESULTS: Data from 28 cross-sectional studies and 14 case-control studies were extracted. There was strong evidence for transmission by direct contact with dogs for both CE and AE. The estimated attributable fractions were 26.1% (CI 13.8%-39.6%) and 34.4% (CI 20.7% -48.2%) respectively. Transmission through contaminated water was estimated to be responsible for approximately 29.4% (CI 12.1%-51.7%) for CE and 24.8% (CI 10.6% to 42.6%) for AE. Contaminated food may be responsible for approximately 23.4% of CE cases (CI 2.1%-47.3%). Globally, there was insufficient evidence to conclude AE can be transmitted by food, although case control studies from low human incidence areas suggested that possibly 32.5% (CI 10.0%-53.2%) could be transmitted by food. There was also insufficient evidence that direct contact with foxes was a significant source of human disease. There were no suitable studies with a risk of environmental contact reported, but the residual attributable fraction thatwould likely include this pathway was approximately 21.1% for CE and 11.1% for AE. CONCLUSIONS: The results support the hypothesis that dog contact and drinking contaminated water are major pathways of transmission of both CE and AE. For contaminated food, the results are less consistent, but suggest that it is an important transmission pathway and provide better evidence than expert elicitations as previously used.


Assuntos
Equinococose/epidemiologia , Equinococose/transmissão , Animais , Estudos de Casos e Controles , Estudos Transversais , Bases de Dados Factuais , Cães , Alimentos , Contaminação de Alimentos , Raposas , Humanos , Modelos Logísticos , Razão de Chances , Fatores de Risco
14.
Vet Parasitol ; 163(1-2): 93-100, 2009 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-19380206

RESUMO

Trichinella surveillance in wildlife has relied on the detection of muscle larvae using digestion techniques. Serology has been proposed as more suitable for large-scale epidemiological studies in wildlife. In this study, 328 individual sera from wild red foxes and 16 sera from experimentally infected farmed foxes were serologically tested with both excretory/secretory antigen (E/S) and the synthetic beta-tyvelose glycan antigen, in indirect ELISA tests. The wild red foxes (Vulpes vulpes) had previously been examined for muscle larvae, using muscle digestion, whilst the experimentally infected farmed foxes were inoculated per os with either a low dose, 500 larvae, or a high dose, 10,000 of Trichinella nativa muscle larvae. Western blot (WB) was carried out on all seropositive samples using crude larval antigen. The present study found both beta-tyvelose and E/S antigen suited for the detection of antibodies to Trichinella spp., and T. nativa in particular, in foxes. Both ELISA antigens performed well, although, the E/S antigen was superior to the beta-tyvelose antigen, with sera that had been stored at -20 degrees C for more than 10 years. Neither antigen, however, detected all of the samples proven seropositive by WB: E/S detected 21 of the 27 wild red fox sera positive by WB; beta-tyvelose detected 22 positive sera; and in total 24 of the 27 positive WB sera were identified using both antigens. Serology alone, without WB or muscle digestion, led to a two- to threefold higher seroprevalence estimate, respectively. The use of E/S antigen in conjunction with the WB was the method of choice for the screening of wild red fox populations for Trichinella. Antibody persistence to T. nativa was short in the low dose group where antibody levels were not different from background by 32 wpi. In total, 7.3% (24/328) of the wild red fox population had antibodies to Trichinella on ELISA and WB. Antibodies were identified in foxes from a further two regions in Norway compared to the original muscle digestion results.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Raposas/parasitologia , Testes Sorológicos/veterinária , Trichinella/imunologia , Triquinelose/veterinária , Agricultura , Animais , Ensaio de Imunoadsorção Enzimática/veterinária , Raposas/imunologia , Músculo Esquelético/parasitologia , Noruega , Triquinelose/sangue , Triquinelose/imunologia
15.
Vet Parasitol ; 155(1-2): 59-66, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18513873

RESUMO

Ingestion of eggs of the small fox tapeworm, Echinococcus multilocularis, causes the severe human disease alveolar echinococcosis. Previously, the dynamics of the egg excretion from infected carnivores have been studied only where the host animals have been exposed to a single experimental infection. In nature, foxes are most likely repeatedly infected. To study the effect of repeated exposure, twenty-one foxes were inoculated with a high dose of E. multilocularis protoscoleces three times over a 1-month period. For comparative purposes, three groups of twenty-one foxes were respectively inoculated with low, medium, or high single dose of protoscoleces. For each group, worm number and morphology were analyzed after necropsy of seven foxes at 1, 2, and 4 months after last inoculation. The establishment of intestinal worms was very low in all foxes, and surprisingly, most of the worms did not produce eggs. Although most reproductive structures were detectable, the genital pore and the cirrus pouch often had abnormal enlargements that spread internally, most likely preventing the reproductive function. The reason for this abnormality could not be determined, but the preparation and storage conditions of the inoculated protoscoleces may have contributed to the stunted development. Physical stress of E. multilocularis at the larval stage in rodents may later adversely affect the reproductive success of the adult tapeworm in the carnivore definitive host; as in the present study where a worm establishment in the definitive host was only followed by a neglectable egg production.


Assuntos
Equinococose/veterinária , Echinococcus multilocularis/fisiologia , Raposas/parasitologia , Óvulo/fisiologia , Animais , Equinococose/parasitologia , Fezes/parasitologia , Feminino , Interações Hospedeiro-Parasita , Contagem de Ovos de Parasitas , Reprodução , Fatores de Tempo
16.
Parasit Vectors ; 10(1): 4, 2017 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-28049507

RESUMO

BACKGROUND: Infections and clinical cases of Angiostrongylus vasorum in dogs are found increasingly across Europe, thus rendering knowledge on its infection biology more important. We used red foxes as a carnivore model to examine the effect of host age and infection dose on the establishment of adult A. vasorum in single experimental infections. METHODS: Fourteen juvenile and fourteen adult red foxes, free of metastrongyloid infections, were given a low (50) or high (200) dose of third-stage larvae (L3) of A. vasorum. Two groups of three foxes of each age group served as uninfected controls. Larval excretion by Baermann and blood parameters were followed for ten weeks. Worm counts were performed at necropsy by sequential perfusion, dissection and Baermann method. RESULTS: The establishment rate (i.e. recovery in percentage of inoculation dose) of A. vasorum primary infections in red foxes was associated with host age and inoculation dose. In the low dose juveniles, 61% (range 52-72%) of the infection dose was recovered as worms in the pulmonary arteries and heart at necropsy while only 35% (21-50%) were recovered in the high dose. Corresponding establishment rates for adults were 39% (18-98%) and 8% (1-21%). In juveniles, a higher dose resulted in significantly higher adult worm counts, higher larval excretion and more pronounced pathophysiological changes, particularly in coagulation parameters. Earlier onset of patency was also found in the juveniles. In contrast, the larval excretion in high dose adults was very low and two infected animals never reached patency. However, a few adults showed only limited resistance as judged by excretion of larvae. The increase to very high larval excretion levels (> 4,000 larvae per g of faeces) after several months in a single animal, indicated that any potential acquired immunity does not affect worm fecundity. CONCLUSIONS: Resistance to a primary A. vasorum infection was generally higher in older animals, and this age resistance was reflected in lower worm counts and reduced excretion of larvae. The juvenile red foxes were fully susceptible, as reflected in high establishment rates. Although severe clinical disease was never observed in the foxes, A. vasorum infections in red foxes appear to be chronic and moreover, to resemble infections in dogs. The results underline the red fox as a suitable model as well as natural reservoir for the parasite.


Assuntos
Angiostrongylus/crescimento & desenvolvimento , Raposas/parasitologia , Infecções por Strongylida/patologia , Infecções por Strongylida/parasitologia , Fatores Etários , Animais , Resistência à Doença , Europa (Continente) , Carga Parasitária
17.
Vet Parasitol ; 141(3-4): 243-50, 2006 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-16822617

RESUMO

Canine alveolar echinococcosis (AE) is a rare liver disease caused by the larval stage (metacestode) of E. multilocularis. Its diagnosis so far is rather difficult and invasive. Imaging techniques for the diagnosis have been described recently and in this study, the serological diagnosis of canine AE was evaluated in 30 dogs with confirmed AE using ELISA based on seven different antigens (E. multilocularis-antigens: Em2G11, EmII/3-10, protoscolex (EmP), excretory/secretory and adult integument (EmAd/I); E. granulosus antigens: hydatid fluid (EgHF) and antigen B (EgAgB)) and by the detection of circulating Em2G11-antigen. EmII/3-10 and Em2G11-based tests detected AE in 50 and 53%. The combined serological investigation for specific circulating Em2G11-antigen and specific antibodies against this antigen showed a sensitivity of 77%. This strategy is useful in animals with large parasite masses and ascites. The highest sensitivities for AE were obtained by the EmAd/I and the EmP antigens (97 and 93% sensitivity) with high specificities in the control group of 76 dogs (100 and 98.7%, respectively). Heterologous E. granulosus antigens (EgHF and EgAgB) showed low sensitivities (43 and 50%, respectively) with high numbers of unspecific reactions (>16%) in the control group. In the follow-up of four dogs, the serological reaction patterns against the antigens Em2G11, EmP and EmAd/I showed some correlations with the development of the parasite mass. Intestinal infections cannot be differentiated from AE by most antigens (except EmII/3-10) and have to be excluded by the absence of coproantigens or DNA of E. multilocularis in faecal samples.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/imunologia , Doenças do Cão/diagnóstico , Equinococose Hepática/veterinária , Echinococcus multilocularis/imunologia , Animais , Diagnóstico Diferencial , Doenças do Cão/sangue , Cães , Equinococose Hepática/sangue , Equinococose Hepática/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Seguimentos , Masculino , Distribuição Aleatória , Sensibilidade e Especificidade , Testes Sorológicos/veterinária
18.
J Parasitol ; 92(6): 1196-201, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17304794

RESUMO

Toxocara canis, an intestinal helminth of canids with zoonotic potential, was found in 618 (59%) of 1,040 red foxes (Vulpes vulpes) collected from all Danish provinces (1997-2002). The prevalence and average worm burden were significantly higher for cubs than older foxes and in males than in females. A multiple logistic regression demonstrated that the prevalence was influenced significantly by sex and age of foxes in addition to location, season, and year of collection. The highest prevalence and worm burden were found in rural areas. The size and number of female worms was positively correlated to the fecal egg excretion. The length and fecundity of the worms was significantly higher in male foxes, and a general intensity dependence was suggested from a negative correlation between worm numbers and worm lengths. As compared to intestinal recovery of worms, somatic larvae were recovered from 20% of muscle samples and fecal eggs in 41% of fecal samples. The consistent finding of T. canis larvae in somatic tissues of naturally infected foxes is new.


Assuntos
Raposas/parasitologia , Toxocara canis/isolamento & purificação , Toxocaríase/epidemiologia , Distribuição por Idade , Animais , Distribuição Binomial , Dinamarca/epidemiologia , Fezes/parasitologia , Feminino , Fertilidade , Membro Anterior , Intestinos/parasitologia , Rim/parasitologia , Modelos Lineares , Masculino , Músculo Esquelético/parasitologia , Contagem de Ovos de Parasitas/veterinária , Dinâmica Populacional , Prevalência , Estações do Ano , Distribuição por Sexo , Toxocara canis/crescimento & desenvolvimento , Toxocara canis/fisiologia , Toxocaríase/parasitologia , Zoonoses
19.
J Travel Med ; 23(5)2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27296583

RESUMO

We report here three cases of trichinellosis due to polar bear meat consumption in East Greenland. In the past 20 years, 31 cases of trichinellosis have been reported in French travellers to the Arctic (North Quebec, Nunavut and Greenland) who consumed undercooked meat from black, brown, or polar bears. If local communities are increasingly becoming aware of the risk of trichinellosis, travellers visiting regions where bear meat is consumed should be informed of the risk of eating raw or non-heat-processed meats.


Assuntos
Animais Selvagens/parasitologia , Carne/parasitologia , Triquinelose/diagnóstico , Ursidae , Adulto , Animais , Feminino , Parasitologia de Alimentos , Groenlândia , Humanos , Masculino , Triquinelose/parasitologia
20.
Vet Parasitol ; 215: 48-57, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26790737

RESUMO

The therapeutic potential of infective pig whipworm eggs, Trichuris suis ova (TSO), is currently tested in several clinical trials on immune-mediated diseases. This paper studied the embryonic development of TSO in a medicinal raw product, where the parasite eggs were suspended in sulphuric acid (pH1). Unembryonated T. suis egg batches were stored at 5, 10, 15, 20, 25, 30, and 40°C (±1°C) and examined at 2, 4, 8, and 14 weeks. Subsequently, sub-batches from each temperature were allowed to embryonate for additional 14 weeks at 25°C, and selected samples were tested for infectivity in Göttingen minipigs. Both male and female pigs were used to evaluate eventual gender specific infectivity. Storage at 30°C up to 14 weeks and subsequent embryonation for 14 weeks at 25°C did not significantly reduce the overall larval establishment in minipigs, as compared to storage at 5°C and subsequent embryonation at 25°C. As marked impairment of egg development was observed during storage at 40°C, a second set of unembryonated egg batches were incubated at 30, 32, 34, 36, 38, and 40°C (±1°C) for 1-8 weeks. The development of the eggs was repeatedly examined by manual light microscopy, multispectral analysis (OvaSpec), and an egg hatching assay prior to the final testing in minipigs (Trial 1). These methods showed that the development started earlier at higher temperatures, but the long-term storage at higher temperature affected the egg development. The present study further documents tolerance of the TSO to storage at temperature 5-15°C, at which temperature development of larvae is not initiated.


Assuntos
Óvulo/fisiologia , Temperatura , Trichuris/embriologia , Animais , Feminino , Larva/crescimento & desenvolvimento , Masculino
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA