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1.
J Helminthol ; 94: e96, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31679534

RESUMO

Toxocariasis is an emerging zoonotic disease caused by Toxocara canis and T. cati. Toxocariasis and its etiological agents are of global public health importance, whose burden appears underestimated, especially in sub-Saharan Africa (SSA). The diversity in the transmission routes of these parasites contributes to disease prevalence and often hinders disease control measures. This study aimed to review the epidemiological distribution of Toxocara infections in SSA region. A systematic review and meta-analysis were performed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis). We identified 94 relevant, peer-reviewed articles, out of which, 75 articles were found eligible based on Toxocara infections in dogs, cats and humans. Overall, 27,102 samples were examined for T. canis in dogs, T. cati in cats and Toxocara serology in humans, out of which 6142 were positive for Toxocara infection: 3717 (13.7%) in dogs (faecal, 3487; necropsy, 180; hair, 50); 266 (1%) in cats (faecal, 101; necropsy, 165); and 2159 (8%) in humans (serology). Overall mean prevalences of 19% (95% confidence interval (CI): 14-23%), 9% (95% CI: 0-28%) and 36% (95% CI: 24-49%) were recorded in dogs, cats and humans, respectively. Substantial heterogeneity was observed between studies and subgroups (I2 = 99%, P < 0.01). Findings from the review showed that studies on the epidemiology of Toxocara infections in the SSA region are limited. We strongly recommend focused, collaborative and coordinated studies to determine Toxocara spp. prevalence in various hosts, including food animals and the environment, through a 'One Health' approach across SSA countries.


Assuntos
Doenças do Gato/parasitologia , Doenças do Cão/parasitologia , Toxocaríase/parasitologia , África ao Sul do Saara/epidemiologia , Animais , Doenças do Gato/epidemiologia , Doenças do Gato/transmissão , Gatos , Doenças do Cão/epidemiologia , Doenças do Cão/transmissão , Cães , Fezes/parasitologia , Humanos , Toxocara/classificação , Toxocara/genética , Toxocara/isolamento & purificação , Toxocara/fisiologia , Toxocaríase/epidemiologia , Toxocaríase/transmissão , Zoonoses/parasitologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-31778390

RESUMO

Public parks are leisure environments widely used by both, adults and children, often accompained by their pets. Soil contamination of these environments by enteric viruses and intestinal parasites occurs through these animals feces. The aim of this work was to detect Carnivore protoparvovirus 1 (CPV-1) and different species of Mastadenovirus in soils samples from a park located in a medium-sized city in Brazil and evaluate the presence of helminth eggs and larvae in 18 points of a public park soil samples, as well as feces found on this site during six months. Parasitological analyzes were conducted through flotation and sedimentation techniques, and polymerase chain reaction (PCR) was used for viral detection. Of the 216 soil and 16 feces samples, 49% (106/216) and 12% (2/16) were positivefor nematodes larvae, respectively, through sedimentation techniques. Toxocara spp eggs were found in one soil sample and one feces sample, Trichuris spp eggs were found in only one feces sample and Hookworms eggs were found in four soil samples. After reconstruction work in the streets near the park, 30% (64/216) of the samples were positive for Human Mastadenovirus C (HAdV-C), 1.4% (3/216) for HAdV-E and 0.4% (1/216) for Canine Mastadenovirus A (CAdV-A). The parasitic forms found in this study have demonstrated that the contamination of the park's soil pose a threat to human and animal health. This was the first study to report the presence of HAdVs and CAdVs in soil samples.


Assuntos
Ancylostomatoidea/isolamento & purificação , Mastadenovirus/isolamento & purificação , Microbiologia do Solo , Solo/parasitologia , Toxocara/isolamento & purificação , Ancylostomatoidea/classificação , Ancylostomatoidea/genética , Animais , Cães , Fezes/parasitologia , Humanos , Mastadenovirus/classificação , Mastadenovirus/genética , Parques Recreativos , Reação em Cadeia da Polimerase em Tempo Real , Toxocara/classificação , Toxocara/genética
3.
J Helminthol ; 93(3): 306-312, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-29733009

RESUMO

Human toxocariasis, a worldwide parasitic disease, is caused by the larval stage of intestinal nematodes of dogs and cats, namely Toxocara canis and Toxocara cati. Human infection occurs by the accidental ingestion of embryonated eggs present in the soil, vegetables or on other contaminated surfaces, as well as via consumption of uncooked paratenic hosts, such as bird meat and giblets. The objective of this study was to evaluate the contamination of soil in public parks and playgrounds in Shiraz using microscopy and molecular methods. A total of 150 soil samples were collected from public parks and playgrounds in various areas of Shiraz, southern Iran. The samples were treated with saturated zinc sulphate solution, and Toxocara spp. eggs were detected by microscopic observation followed by nested polymerase chain reaction (PCR). To differentiate T. canis and T. cati eggs from each other, PCR restriction fragment length polymorphism (RFLP) of the internal transcribed spacer (ITS)-rDNA region by SalI endonuclease enzyme was used. PCR-sequencing was performed to confirm the results of the PCR-RFLP method. Based on the flotation results of the 150 soil samples, six (4%) were found to be positive for Toxocara spp. eggs, whereas nested-PCR showed 24 samples to be positive (16%). Based on the PCR-RFLP method and the sequence of the ITS-rDNA region, a total of 23 out of 24 isolates were confirmed as T. cati and one out of 24 as T. canis. The results showed a higher number of soil samples to be positive for Toxocara by the molecular method than microscopy, and higher T. cati infection in soil samples, which could have an important role in human infection with toxocariasis in this region.


Assuntos
Solo/parasitologia , Toxocara/isolamento & purificação , Animais , Análise por Conglomerados , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Irã (Geográfico) , Microscopia , Parasitologia/métodos , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA , Toxocara/classificação , Toxocara/genética
4.
Vet Parasitol ; 262: 16-19, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30389006

RESUMO

To find out the transmission routes for Toxocara infection, the possibility of transfer of Toxocara eggs from the soil on the paws of animals and on the shoes of people was explored. For this purpose, a study was conducted to find helminth eggs in washings from the paws of dogs after walking, from the shoes of their owners, as well as non-dog owners. Toxocara eggs were detected in 19.4% of the dogs' paws washings and in 11.4% of washings from the shoes of their owners. The number of eggs found on the paws was about twice as high as on the shoes. The mean number of eggs in the sample was 2.9 in washings from the paws and 1.8 from the shoes. In the samples, Toxocara cati eggs prevailed both in occurrence and in abundance. Out of the total number of positive samples, the eggs of T. cati were found in 83%, and T. canis in 42%. 79% of the found eggs belonged to T. cati and 21% to T. canis. In the washings from shoes of people that do not own dogs, the eggs of parasites were not found. This study demonstrates that the helminth eggs can be transferred from contaminated soil to people's homes on the paws and shoe soles. Even animals without a patent infection may take part in propagation of infection causing risks of human toxocariasis. In dogs, in addition, the transferred on paws T. canis eggs can serve as a causative agent of permanent, cumulative subclinical infection with a deferred manifestation in posterity. It is supposed that infestation "through the paws" is one of the probable routes of transmission of toxocariasis in dogs.


Assuntos
Doenças do Cão/parasitologia , Toxocara/classificação , Toxocaríase/parasitologia , Animais , Doenças do Cão/transmissão , Cães , Humanos , Contagem de Ovos de Parasitas/veterinária , Solo/parasitologia , Toxocara/citologia , Toxocara/isolamento & purificação , Toxocara canis/classificação , Toxocara canis/citologia , Toxocaríase/transmissão
5.
Arq. bras. med. vet. zootec. (Online) ; 70(1): 1-5, Jan.-Feb. 2018. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-888102

RESUMO

Both the presence of owned dogs and stray dogs allows the spread of Toxocara, a parasite whose eggs can be found in soil, water and food. Animals, including horses, serve as definitive and paratenic hosts. In México, where consumption of horse meat is common, Toxocara is a zoonotic parasite. The aim of this study was to identify the presence of anti-Toxocara antibodies in work horses and horses intended for human consumption by ELISA. ELISA was chosen for analysis as paratenic hosts do not shed Toxocara eggs in their feces. Blood samples were collected from a total of 188 horses, 94 of which were work horses and 94 horses from the slaughter house. Samples were analyzed by ELISA, and the general equine seroprevalence was found to be 44.6% (n = 188). Adult horses for slaughter had a 61.7% greater presence of anti-Toxocara antibodies (p = 0.006). Toxocara IgG antibodies were found in horses, confirming that horses are paratenic hosts and possible sources of infection for other animals and people.(AU)


Tanto a presença de cães com dono quanto de cães vadios permitem a disseminação de Toxocara, e o parasita está presente no solo, na água e nos alimentos. Animais, incluindo cavalos, apresentam-se como hospedeiros definitivos e paratênicos. No México, o consumo de carne de cavalo é comum, e Toxocara é um parasita zoonótico. ELISA foi escolhido para análise, já que hospedeiros paratênicos não jogam ovos de Toxocara em suas fezes. O objetivo deste estudo foi identificar a presença de anticorpos anti-Toxocara por ELISA, em cavalos de trabalho e em cavalos para o consumo humano. As amostras de sangue foram retiradas de 188 cavalos: 94 cavalos de trabalho e 94 cavalos de trabalho do matadouro. Soros dos animais foram analisados por ELISA e 44,6% dos equinos apresentaram anticorpos anti-Toxocara. Cavalos adultos para abate têm 61,7% mais elevada a presença de anticorpos anti-Toxocara (P = 0,006). Anticorpos IgG Toxocara foram encontrados em cavalos, confirmando cavalos paratênicos como hospedeiros e possíveis fontes de infecção para outros animais e pessoas.(AU)


Assuntos
Animais , Cavalos/imunologia , Imunoglobulina G/classificação , Toxocara/classificação , Zoonoses
6.
Am J Trop Med Hyg ; 97(6): 1846-1850, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29016316

RESUMO

Caused by the parasitic nematodes Toxocara canis and cati, toxocariasis in humans can result in covert toxocariasis, ocular toxocariasis, visceral larval migrans, and neurotoxocariasis. A common infection, toxocariasis exposure varies widely within and between countries, with a previous estimate of Toxocara seroprevalence using data from 1988 to 1994 in the United States of approximately 13%. Age, poverty, sex, educational attainment, ethnicity, and region have been associated with Toxocara seroprevalence. In this study, we sought to determine the seroprevalence of and factors associated with Toxocara seropositivity in the United States using data from the National Health and Nutrition Examination Survey from 2011 to 2014 to provide a more recent estimate of Toxocara seroprevalence in the United States. We found an overall Toxocara seroprevalence of 5.1%. Increasing age, male sex, low educational attainment, low income, and immigration status each was associated with Toxocara seropositivity. Mexican Americans had reduced odds of exposure. These findings show that exposure to Toxocara continues in the United States and that several demographic factors influence the risk of exposure.


Assuntos
Toxocara/isolamento & purificação , Toxocaríase/epidemiologia , Animais , Feminino , Humanos , Masculino , Inquéritos Nutricionais , Fatores de Risco , Estudos Soroepidemiológicos , Fatores Socioeconômicos , Toxocara/classificação , Estados Unidos/epidemiologia
7.
Acta Parasitol ; 62(3): 549-556, 2017 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-28682773

RESUMO

The definitive genetic identification of Toxocara species is currently based on PCR/sequencing. The objectives of the present study were to design and conduct an in silico polymerase chain reaction-restriction fragment length polymorphism method for identification of Toxocara species. In silico analyses using the DNASIS and NEBcutter softwares were performed with rDNA internal transcribed spacers, and mitochondrial cox1 and nad1 sequences obtained in our previous studies along with relevant sequences deposited in GenBank. Consequently, RFLP profiles were designed and all isolates of T. canis and T. cati collected from dogs and cats in different geographical areas of Iran were investigated with the RFLP method using some of the identified suitable enzymes. The findings of in silico analyses predicted that on the cox1 gene only the MboII enzyme is appropriate for PCR-RFLP to reliably distinguish the two species. No suitable enzyme for PCR-RFLP on the nad1 gene was identified that yields the same pattern for all isolates of a species. DNASIS software showed that there are 241 suitable restriction enzymes for the differentiation of T. canis from T. cati based on ITS sequences. RsaI, MvaI and SalI enzymes were selected to evaluate the reliability of the in silico PCR-RFLP. The sizes of restriction fragments obtained by PCR-RFLP of all samples consistently matched the expected RFLP patterns. The ITS sequences are usually conserved and the PCR-RFLP approach targeting the ITS sequence is recommended for the molecular differentiation of Toxocara species and can provide a reliable tool for identification purposes particularly at the larval and egg stages.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/genética , Mitocôndrias/enzimologia , NADH Desidrogenase/genética , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Toxocara/genética , Animais , DNA Mitocondrial/genética , DNA Espaçador Ribossômico/genética , Regulação Enzimológica da Expressão Gênica/fisiologia , Mitocôndrias/genética , NADH Desidrogenase/metabolismo , Especificidade da Espécie , Toxocara/classificação
8.
J Vet Diagn Invest ; 29(5): 645-653, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28424002

RESUMO

We report the development and field validation of 2 ELISAs for the detection of Ancylostoma caninum or Toxocara canis coproantigens in the feces of dogs with experimental and natural infections, and evidence of cross-reactivity with respective feline counterparts. A. caninum-specific coproantigens were detected in feces of experimentally infected dogs starting at 9 d post-infection (dpi), whereas eggs were not seen until 23 dpi. T. canis-specific coproantigens were detected in 3 of 5 experimentally infected dogs by 31 dpi, and 4 of the 5 animals by 38 dpi. T. canis eggs were seen in feces of 4 of the 5 animals by 38 dpi. One dog had delayed coproantigen detection and low egg output. Additionally, 817 canine and 183 feline fecal samples from naturally infected animals tested by flotation were subjected to coproantigen ELISA testing. Of these 1,000 canine and feline samples, 13 and 23 samples, respectively, were positive for "hookworm" or "roundworm" eggs; 19 and 26 samples were ELISA positive, respectively. The T. canis ELISA detected T. cati coproantigen in cat fecal samples. Discrepant ELISA and flotation results were obtained for 16 hookworm- and 13 roundworm-positive samples. Re-examination of the egg-positive, ELISA-negative samples indicated several instances of possible misidentification or coprophagy, whereas detection of antigen in samples without egg observations is likely a reflection of true infection status with egg shedding below detection levels. There is good indication, based on accumulated field data, that these antigen tests also detect other hookworm and ascarid species.


Assuntos
Ancylostoma/isolamento & purificação , Ancilostomíase/veterinária , Doenças do Gato/parasitologia , Doenças do Cão/parasitologia , Toxocara/isolamento & purificação , Toxocaríase/diagnóstico , Ancylostoma/imunologia , Ancilostomíase/diagnóstico , Animais , Antígenos de Helmintos/isolamento & purificação , Doenças do Gato/diagnóstico , Gatos , Doenças do Cão/diagnóstico , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Fezes/química , Fezes/parasitologia , Óvulo , Toxocara/classificação , Toxocara/imunologia , Toxocara canis/imunologia , Toxocara canis/isolamento & purificação , Toxocaríase/parasitologia
9.
Ann Agric Environ Med ; 24(1): 44-48, 2017 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-28378972

RESUMO

The objective of this study was to evaluate the risk of soil transmitted zoonotic helminth infections for families with young children, inhabitants of villages in the Mazowieckie Province of Central Poland. Epidemiological survey was conducted at 33 randomly selected households with 2-3 children present. Examination of soil samples from yards surrounding the houses for the presence of geohelminth eggs was conducted, the households were inspected, and family members interviewed using a designed questionnaire. Among 55 localities examined, i.e. 33 backyards, 10 vegetable gardens and 12 sandpits, contamination was found in 2 backyards (6.1%) and 1 sandpit (8.3%) at 3 households (9.1%). Of the total 550 examined soil samples, 4 (0.7%) were found to contain Trichuris and Toxocara eggs, with an average density of 1.5 and 2.0 eggs per sample. The study showed a low level of soil contamination, which was the result of inhabitants care about the sanitation of their domiciles. However, the results of the questionnaire survey demonstrated the need to warn rural residents about the risk factors for zoonotic helmints infections. In particular, parents should be advised how to minimize the threat of parasitic diseases for children in the rural environment. The presented study showed that promotional campaigns implemented in recent years on the prevention of parasitic zoonoses have had little effect to increase the awareness of the rural community. The present results confirmed that Toxocara is the most common zoonotic agent among geohelminths in the rural environment.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , População Rural , Solo/parasitologia , Toxocara/isolamento & purificação , Trichuris/isolamento & purificação , Zoonoses/psicologia , Adulto , Animais , Criança , Pré-Escolar , Meio Ambiente , Humanos , Óvulo/classificação , Polônia , Fatores de Risco , População Rural/estatística & dados numéricos , Inquéritos e Questionários , Toxocara/classificação , Trichuris/classificação , Adulto Jovem , Zoonoses/parasitologia
10.
J Helminthol ; 91(5): 633-636, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27571878

RESUMO

Consuming raw and undercooked meat is known to enhance the risk of human toxocariasis because Toxocara species have a wide range of paratenic hosts, including chickens. The aim of this study was to identify species of Toxocara in naturally infected broiler chickens using molecular approaches. A polymerase chain reaction (PCR) method was used for the differentiation of Toxocara canis and Toxocara cati larvae recovered from tissues and organs, and identified by microscopic observations. Thirty-three 35- to 47-day-old broiler chickens were used for examination of Toxocara larvae. The duodenum, liver, lungs, heart, kidneys, skeletal muscles and brain of each chicken were examined using the pepsin method, and DNA from each tissue was extracted as the template for PCR assay. The findings revealed that 5 of 33 (15.2%) broiler chickens were infected with Toxocara larvae. Larvae were recovered from the liver (n = 19), duodenum (n = 8), skeletal muscles (n = 8) and brain (n = 2) of broiler chickens naturally infected with Toxocara spp. The results showed that the frequencies of the species in the chickens were T. canis larvae (n = 5, 83.3%) and T. cati larvae (n = 1, 16.7%). Our data from the present study demonstrated the importance of broiler chickens as a paratenic host for the parasite's life cycle in the environment. The implementation of DNA amplification as a routine diagnostic technique is a specific and alternative method for identification of Toxocara larvae, and allowed the observation of specific species under field conditions within the locations where broiler chickens are typically raised and exposed to Toxocara spp. eggs or larvae.


Assuntos
Galinhas/parasitologia , Técnicas de Diagnóstico Molecular/métodos , Doenças das Aves Domésticas/diagnóstico , Toxocara/classificação , Toxocara/isolamento & purificação , Toxocaríase/diagnóstico , Estruturas Animais/parasitologia , Animais , Reação em Cadeia da Polimerase/métodos , Doenças das Aves Domésticas/parasitologia , Toxocara/genética , Toxocaríase/parasitologia
11.
Korean J Parasitol ; 54(5): 645-652, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27853122

RESUMO

Toxocara vitulorum has been rarely reported in yaks at high altitudes and remote areas of Sichuan Province of Tibetan Plateau of China. The current study was designed to investigate the prevalence, associated risk factors, and phylogenetic characteristics of T. vitulorum in yak calves on the Qinghai Tibetan plateau. Fecal samples were collected from 891 yak calves and were examined for the presence of T. vitulorum eggs by the McMaster technique. A multivariable logistic regression model was employed to explore variables potentially associated with exposure to T. vitulorum infection. T. vitulorum specimens were collected from the feces of yaks in Hongyuan of Sichuan Province, China. DNA was extracted from ascaris. After PCR amplification, the sequencing of ND1 gene was carried out and phylogenetic analyses was performed by MEGA 6.0 software. The results showed that 64 (20.1%; 95% CI 15.8-24.9%), 75 (17.2; 13.8-21.1), 29 (40.9; 29.3-53.2), and 5 (7.6; 2.5-16.8) yak calves were detected out to excrete T. vitulorum eggs in yak calve feces in Qinghai, Tibet, Sichuan, and Gansu, respectively. The present study revealed that high infection and mortality by T. vitulorum is wildly spread on the Qinghai Tibetan plateau, China by fecal examination. Geographical origin, ages, and fecal consistencies are the risk factors associated with T. vitulorum prevalence by logistic regression analysis. Molecular detection and phylogenetic analysis of ND1 gene of T. vitulorum indicated that T. vitulorum in the yak calves on the Qinghai Tibetan plateau are homologous to preveiously studies reported.


Assuntos
Bovinos , Filogenia , Toxocara/classificação , Toxocara/isolamento & purificação , Toxocaríase/epidemiologia , Toxocaríase/parasitologia , Animais , Análise por Conglomerados , Fezes/parasitologia , Feminino , Proteínas de Helminto/genética , Masculino , Prevalência , Fatores de Risco , Análise de Sequência de DNA , Homologia de Sequência , Tibet/epidemiologia , Toxocara/genética
12.
Vet Parasitol ; 226: 74-7, 2016 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-27514888

RESUMO

The Siberian tiger is endangered and is listed by the International Union for the Conservation of Nature; the captive environment is utilized to maintain Siberian tiger numbers. Little information regarding the prevalence of parasites in Siberian tigers is available. A total of 277 fecal samples of Siberian tigers were analyzed in this study. The microscopic analysis indicated the presence of ascarid eggs of Toxascaris leonina and Toxocara cati. The ascarid infection rate was 67.5% in Siberian tigers. The internal transcribed spacer-1 (ITS-1) phylogenetic analysis indicated that T. leonina belonged to Toxascaris and that Toxo. cati belonged to Toxocara. The infestation rate and intensity of T. leonina were higher than those of Toxo. cati. One-way analysis of variance showed that the presence of T. leonina was significantly associated with age (P<0.05). Temperature changes also influenced T. leonina and Toxo. cati infestation, and a rise in temperature caused an increase in the number of T. leonina and Toxo. cati eggs. This study provides a better understanding of ascarid infestation among the captive Siberian tigers and is helpful for the prevention of the spread of infectious parasitic diseases among other tigers in the zoo.


Assuntos
Animais de Zoológico/parasitologia , Tigres/parasitologia , Toxascaríase/veterinária , Toxocaríase/parasitologia , Distribuição por Idade , Animais , China/epidemiologia , Espécies em Perigo de Extinção , Fezes/parasitologia , Contagem de Ovos de Parasitas/veterinária , Filogenia , Reação em Cadeia da Polimerase/veterinária , Prevalência , Temperatura Ambiente , Toxascaríase/complicações , Toxascaríase/epidemiologia , Toxascaríase/parasitologia , Toxascaris/anatomia & histologia , Toxascaris/classificação , Toxascaris/genética , Toxocara/anatomia & histologia , Toxocara/classificação , Toxocara/genética , Toxocaríase/complicações , Toxocaríase/epidemiologia
13.
Infect Genet Evol ; 37: 94-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26584512

RESUMO

Toxocara canis of canids is a parasitic nematode (ascaridoid) that infects humans and other hosts, causing different forms of toxocariasis. This species of Toxocara appears to be the most important cause of human disease, likely followed by Toxocara cati from felids. Although some studies from Malaysia and China have shown that cats can harbor another congener, T. malaysiensis, no information is available about this parasite for other countries. Moreover, the zoonotic potential of this parasite is unknown at this point. In the present study, we conducted the first investigation of domestic dogs and cats for Toxocara in Vietnam using molecular tools. Toxocara malaysiensis was identified as a common ascaridoid of domestic cats (in the absence of T. cati), and T. canis was commonly found in dogs. Together with findings from previous studies, the present results emphasize the need to explore the significance and zoonotic potential of T. malaysiensis in Vietnam and other countries where this parasite is endemic and prevalent in cats.


Assuntos
DNA de Helmintos/análise , Toxocara/classificação , Toxocara/isolamento & purificação , Toxocaríase/parasitologia , Animais , Gatos , Cães , Humanos , Filogenia , Toxocara/genética , Toxocaríase/transmissão , Vietnã , Zoonoses/parasitologia
14.
Parasitol Res ; 114(11): 4289-93, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26319520

RESUMO

Human toxocariasis may be acquired by eating raw chicken liver. However, there are no reports on the prevalence of natural infection of chickens with Toxocara. The aim of this study was to evaluate the presence of anti-Toxocara antibodies as indicators of natural infection with Toxocara, in free-range chickens from Espírito Santo State, Brazil. An ELISA test with secretory and excretory Toxocara canis antigens was used. Negative controls were 20 industrial chickens reared in a high hygiene standard environment. Positive control serum was from a chicken infected with embryonated eggs of T. canis. Sera were adsorbed with Ascaridia galli extract to reduce cross-reactivity. Cut-off was the mean plus four times the standard deviation of optical density (OD) in negative group. One hundred and fifty-seven sera from free-range chicken were investigated. Results showed 58.5% of the chickens were positive with ELISA test; 12.7% had OD over the positive control and may be considered as true infected chickens. The results between the cut-off and the positive control may include infections with low titers of antibodies or may represent serum scar of past infection or may be the result of cross-reaction with other nematodes rather than A. galli which is used for the adsorption of sera. In conclusion, high prevalence of Toxocara sp. antibodies demonstrates natural infection of free-range chickens from Espírito Santo State which may represent a risk of infection with this nematode in people who have the habit of eating raw or undercooked chicken meat or viscera. The results also suggest that chickens may be useful as sentinels to detect soil contaminated with Toxocara eggs.


Assuntos
Doenças das Aves Domésticas/parasitologia , Toxocara/isolamento & purificação , Toxocaríase/parasitologia , Animais , Anticorpos Anti-Helmínticos/imunologia , Brasil/epidemiologia , Galinhas/imunologia , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Humanos , Doenças das Aves Domésticas/imunologia , Prevalência , Toxocara/classificação , Toxocara/imunologia , Toxocaríase/epidemiologia , Toxocaríase/imunologia
15.
Int J Parasitol ; 45(7): 495-503, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25843806

RESUMO

Toxocara canis and Toxocara cati are globally occurring intestinal nematodes of dogs and cats with a high zoonotic potential. Migrating larvae in the CNS of paratenic hosts, including humans, may cause neurotoxocarosis resulting in a variety of neurological symptoms. Toxocara canis exhibits a stronger affinity to the CNS than T. cati, causing more severe neurological symptoms in the mouse model. Pathomechanisms of neurotoxocarosis as well as host responses towards the respective parasite are mostly unknown. Therefore, the aim of this study was to characterise the pathogenesis at a transcriptional level using whole genome microarray expression analysis and identify differences and similarities between T. canis- and T. cati-infected brains. Microarray analysis was conducted in cerebra and cerebella of infected C57Bl/6J mice 42daysp.i. revealing more differentially transcribed genes for T. canis- than T. cati-infected brains. In cerebra and cerebella of T. canis-infected mice, a total of 2304 and 1954 differentially transcribed genes, respectively, were identified whereas 113 and 760 differentially transcribed genes were determined in cerebra and cerebella of T. cati-infected mice. Functional annotation analysis revealed major differences in host responses in terms of significantly enriched biological modules. Up-regulated genes were mainly associated with the terms "immune and defence response", "sensory perception" as well as "behaviour/taxis" retrieved from the Gene Ontology database. These observations indicate a strong immune response in both infection groups with T. cati-infected brains revealing less severe reactions. Down-regulated genes in T. canis-infected cerebra and cerebella revealed a significant enrichment for the Gene Ontology term "lipid/cholesterol biosynthetic process". Cholesterol is a highly abundant and important component in the brain, representing several functions. Disturbances of synthesis as well as concentration changes may lead to dysfunction in signal transduction and neurodegenerative disease. Overall, only a minor overlap of differentially transcribed genes was observed between the two infection groups in both brain parts. Most genes are regulated individually in each infection group, supporting the evident differences of both roundworm species observed in the paratenic host in previous studies. In summary the present study underlines the differences in pathogenicity of T. canis and T. cati. It furthermore provides a comprehensive basis for future analyses over the course of infection as well as functional tests to identify gene regulatory circuits that are crucial for pathogenesis of neurotoxocarosis. The results of this study provide a promising foundation for further specific research to evaluate the particular pathogenetic mechanisms and to identify possible therapeutic targets.


Assuntos
Doenças do Sistema Nervoso Central/parasitologia , Lipídeos/biossíntese , Análise Serial de Proteínas , Toxocara/classificação , Toxocaríase/parasitologia , Animais , Encéfalo/parasitologia , Encéfalo/patologia , Regulação da Expressão Gênica/fisiologia , Camundongos , RNA/genética , RNA/metabolismo , Especificidade da Espécie
16.
Parasite Immunol ; 37(4): 204-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25711956

RESUMO

One of the most common zoonotic helminth infections is caused by species in the genus Toxocara, particularly Toxocara canis and T. cati (Syn. T. mystax). However, their relative contribution to toxocarosis in humans remains largely unknown because causative larvae are seldom recovered and uncertainties regarding the validity of existing serological assays. In this study, we used sera from a pig model experimentally infected with T. canis and T. cati to evaluate whether a Western blot could discriminate between the two species. No proteins were observed that could be used as a diagnostic tool. In addition, a heterogenic protein pattern between individual hosts was found, which was most pronounced in the T. cati-infected pigs. There is therefore an urgent need to optimize and validate current methods or develop new species-specific serological methods in order to implement appropriate control measures.


Assuntos
Western Blotting/métodos , Toxocara canis/isolamento & purificação , Toxocara/isolamento & purificação , Toxocaríase/diagnóstico , Toxocaríase/parasitologia , Animais , Antígenos de Helmintos , Reações Cruzadas , Diagnóstico Diferencial , Modelos Animais de Doenças , Humanos , Especificidade da Espécie , Organismos Livres de Patógenos Específicos , Sus scrofa , Toxocara/classificação , Toxocara canis/imunologia , Toxocaríase/imunologia , Zoonoses/diagnóstico , Zoonoses/imunologia , Zoonoses/parasitologia
17.
Acta Trop ; 135: 50-4, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24695242

RESUMO

In the present study, the microscopy and polymerase chain reaction methods were used for detection and identification of soil contamination by Toxocara eggs in squares, streets, public parks, and rubbish dumps in Ahvaz, southwestern Iran. A total of 210 soil samples were collected from different parts of the city and examined by microscopy and polymerase chain reaction (PCR) methods, following sodium nitrate flotation. Nucleotide sequencing was performed to confirm the results of the PCR method. Toxocara eggs were found in 64 and 71 soil samples using the microscopy and PCR methods, respectively. The highest contamination rate was observed in the central part of Ahvaz (39.5% and 46.5% by the microscopy and PCR methods, respectively). Based on internal transcribed spacer 2 (ITS2) PCR identification, 28% of the samples were diagnosed as Toxocara cati and 5.7% as Toxocara canis; no mixed contamination was observed. DNA sequencing of the ITS2 gene confirmed our findings. Compared to the conventional microscopic detection following by flotation, used as the gold standard, the PCR method appears to be rapid and sensitive as well as allows analysis of Toxocara spp. isolated from soil independent of the stage of egg development. Therefore, the PCR method appears to be a valuable tool for the diagnosis and differentiation of Toxocara spp. from soil samples in epidemiological studies, and will help the local health systems in effective prevention and control of disease.


Assuntos
Microbiologia Ambiental , Fezes/parasitologia , Toxocara/classificação , Toxocara/genética , Animais , DNA Intergênico/química , DNA Intergênico/genética , Coleta de Dados , Humanos , Irã (Geográfico) , Microscopia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Toxocara/isolamento & purificação
18.
Parasit Vectors ; 7: 194, 2014 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-24754900

RESUMO

BACKGROUND: Infective larvae of the worldwide occurring zoonotic roundworm T. canis exhibit a marked affinity to the nervous tissues of paratenic hosts. In humans, most cases of neurotoxocarosis are considered to be caused by larvae of T. canis as T. cati larvae have rarely been found in the CNS in previous studies. However, direct comparison of studies is difficult as larval migration depends on a variety of factors including mouse strains and inoculation doses. Therefore, the present study aims to provide a direct comparison of both roundworm species in mice as a model for paratenic hosts with specific focus on the CNS during the acute and chronic phase of disease to provide a basis for further studies dealing with neurotoxocarosis. METHODS: C57Bl/6J mice were infected with 2000 embryonated T. canis and T. cati eggs, respectively as well as Balb/c mice infected with T. cati eggs only. On 8 time points post infection, organs were removed and microscopically examined for respective larvae. Special focus was put on the CNS, including analysis of larval distribution in the cerebrum and cerebellum, right and left hemisphere as well as eyes and spinal cord. Additionally, brains of all infection groups as well as uninfected controls were examined histopathologically to characterize neurostructural damage. RESULTS: Significant differences in larval distribution were observed between and within the infection groups during the course of infection. As expected, significantly higher recovery rates of T. canis than T. cati larvae were determined in the brain. Surprisingly, significantly more T. canis larvae could be found in cerebra of infected mice whereas T. cati larvae were mainly located in the cerebellum. Structural damage in brain tissue could be observed in all infection groups, being more severe in brains of T. canis infected mice. CONCLUSIONS: The data obtained provides an extensive characterization of migrational routes of T. canis and T. cati in the paratenic host mouse in direct comparison. Even though to a lesser extent, structural damage in the brain was also caused by T. cati larvae and therefore, the potential as pathogenic agents should not be underestimated.


Assuntos
Encefalopatias/parasitologia , Cerebelo/parasitologia , Cérebro/parasitologia , Toxocara/classificação , Toxocara/fisiologia , Toxocaríase/parasitologia , Animais , Encefalopatias/patologia , Larva , Camundongos , Especificidade da Espécie , Distribuição Tecidual , Toxocaríase/patologia
19.
Pak J Biol Sci ; 16(22): 1557-62, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24511700

RESUMO

Since the integrity of Toxocara vitulorum cuticle is essential for the nutritive and protective functions, light and scanning electron microscopic studies were undertaken to assess, for the first time, whether the Nigella sativa oil (NSO) had any effect on the cuticle of adult T. vitulorum following incubation in vitro. Differences in response to NSO action were observed, depending on the used concentration. After 24 h incubation with 0.5 mg mL(-1) NSO, the cuticle of the anterior end of worms appeared to be slightly more swollen than normal. This swelling became pronounced and so severe, with lips showed wrinkled cuticular surface and deformed sensory papillae on increasing the concentration to 1.0 mg mL(-1). With the higher concentration of 1.5 mg mL(-1), extensive and severe disorganization of the cuticle and body musculature was observed. Structural alterations in the cuticle as observed in the present investigation were thus, clear indication of nematocidal activity of NSO that could offer a suitable and cheaper alternative for the more expensive anthelmintics.


Assuntos
Antinematódeos/farmacologia , Nigella sativa , Óleos Vegetais/farmacologia , Toxocara/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Microscopia Eletrônica de Varredura , Fitoterapia , Plantas Medicinais , Fatores de Tempo , Toxocara/classificação , Toxocara/crescimento & desenvolvimento , Toxocara/ultraestrutura
20.
J Helminthol ; 87(4): 432-42, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23069601

RESUMO

Some parasitic nematodes can inhabit different definitive hosts, which raises the question of the intraspecific variability of the nematode genotype affecting their preferences to choose particular species as hosts. Additionally, the issue of a possible intraspecific DNA microheterogeneity in specimens from different parts of the world seems to be interesting, especially from the evolutionary point of view. The problem was analysed in three related species - Toxocara canis, Toxocara cati and Toxascaris leonina - specimens originating from Central Europe (Poland). Using specific primers for species identification, internal transcribed spacer (ITS)-1 and ITS-2 regions were amplified and then sequenced. The sequences obtained were compared with sequences previously described for specimens originating from other geographical locations. No differences in nucleotide sequences were established in T. canis isolated from two different hosts (dogs and foxes). A comparison of ITS sequences of T. canis from Poland with sequences deposited in GenBank showed that the scope of intraspecific variability of the species did not exceed 0.4%, while in T. cati the differences did not exceed 2%. Significant differences were found in T. leonina, where ITS-1 differed by 3% and ITS-2 by as much as 7.4% in specimens collected from foxes in Poland and dogs in Australia. Such scope of differences in the nucleotide sequence seems to exceed the intraspecific variation of the species.


Assuntos
DNA de Helmintos/genética , DNA Espaçador Ribossômico/genética , Toxascaríase/veterinária , Toxascaris/classificação , Toxascaris/isolamento & purificação , Toxocara/classificação , Toxocara/isolamento & purificação , Animais , Sequência de Bases , DNA de Helmintos/química , DNA Espaçador Ribossômico/química , Cães , Feminino , Variação Genética , Masculino , Dados de Sequência Molecular , Polônia , Análise de Sequência de DNA , Toxascaríase/parasitologia , Toxascaris/genética , Toxocara/genética
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