Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 19 de 19
Filter
1.
Trends Parasitol ; 40(8): 717-730, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39013660

ABSTRACT

The protozoan parasites Plasmodium, Leishmania, and Trypanosoma are transmitted by hematophagous insects and cause severe diseases in humans. These infections pose a global threat, particularly in low-resource settings, and are increasingly extending beyond the current endemic regions. Tropism of parasites is crucial for their development, and recent studies have revealed colonization of noncanonical tissues, aiding their survival and immune evasion. Despite receiving limited attention, cumulative evidence discloses the respiratory system as a significant interface for host-pathogen interactions, influencing the course of (co)infection and disease onset. Due to its pathophysiological and clinical implications, we emphasize that further research is needed to better understand the involvement of the respiratory system and its potential to improve prevention, diagnosis, treatment, and interruption of the chain of transmission.


Subject(s)
Plasmodium , Animals , Humans , Plasmodium/physiology , Respiratory System/parasitology , Trypanosoma/physiology , Insecta/parasitology , Insect Vectors/parasitology , Leishmania/physiology , Protozoan Infections/parasitology , Protozoan Infections/transmission , Leishmaniasis/transmission , Leishmaniasis/parasitology
3.
Pesqui. vet. bras ; 30(8): 641-645, ago. 2010. tab
Article in Portuguese | LILACS | ID: lil-559897

ABSTRACT

Os protozoários Neospora caninum e N. hughesi infectam os equinos e podem provocar diferentes sinais clínicos associados a problemas reprodutivos ou a distúrbios neurológicos, respectivamente. A patogenia da neosporose é pouco conhecida nos equinos, bem como as fontes de infecção horizontal de N. hughesi. Além disso, há dúvidas quanto ao papel da transmissão vertical de Neospora spp. na sua manutenção em populações equinas. Neste estudo avaliaram-se: (1) a ocorrência da infecção por Neospora spp. na população de éguas em idade reprodutiva em um haras de cavalos da raça Crioula; e (2) a possível associação entre o status sorológico destas éguas com o de suas crias, como meio de investigar, indiretamente, a relevância da transmissão transplacentária na ocorrência da infecção por Neospora spp. nestes animais. A associação entre o status sorológico das éguas e o de suas crias foi altamente significativa. Os animais descendentes de éguas soropositivas tiveram maior ocorrência de anticorpos anti-Neospora spp. do que os descendentes de éguas soronegativas, embora expostos aos mesmos fatores de risco ambientais. A associação entre parentesco em primeiro grau e status sorológico indica a influência da infecção vertical (transplacentária) na ocorrência de Neospora spp. na população equina estudada.


Neospora caninum and N. hughesi are protozoa which can infect horses and can cause reproductive and neurological diseases, respectively. The pathogenesis of neosporosis in horses is poorly understood, as well as the sources of horizontal infection of N. hughesi. Furthermore, there are doubts about the role of the vertical transmission of Neospora spp. in maintenance of these parasites in equine populations. In this study, we evaluated: (1) the occurrence of infections by Neospora spp. in a population of mares (in reproductive age) on a farm of Crioula breed horses; and (2) the possible association between the serological status of mares and of their offspring, aiming to investigate, indirectly, the relevance of transplacental transmission for the occurrence of Neospora spp. in these horses. We found a highly significant association between the serological status of mares and their offspring. Although had been exposed to the same environmental risk factors, the descendants of seropositive mares had a higher percentage of seropositivity against Neospora spp. compared to the descendants of seronegative mares. The association between kinship and serological status indicates an influence of vertical (transplacental) infection raising the occurrence of Neospora spp. in the studied equine population.


Subject(s)
Animals , Female , Pregnancy , Antibodies, Protozoan/adverse effects , Diagnosis/analysis , Protozoan Infections/immunology , Protozoan Infections/pathology , Protozoan Infections/transmission , Reproduction/immunology , Serologic Tests/methods , Serologic Tests/veterinary , Maternal-Fetal Relations , Infectious Disease Transmission, Vertical/veterinary
4.
Rev. panam. salud pública ; 27(6): 414-422, jun. 2010. tab
Article in English | LILACS | ID: lil-555982

ABSTRACT

OBJECTIVES: To determine 1) the degree of soil contamination by parasites; 2) the prevalence of contaminated samples; 3) the overall number of parasitic forms, by distance between the collection site and the domicile; 4) the mean number of parasite forms per peri-household area; and 5) the variables associated with the total number of parasite forms. METHODS: Soil samples were collected in the peridomicile of 18 (out of a total sample of 63) and 22 (out of 190) residences of the Faxinal and Ivaí indigenous territories (ITs), respectively, from March 2005 through October 2006, and evaluated by the methods of Baermann, modified Faust et al., and Lutz. RESULTS: The overall prevalence of samples contaminated by enteroparasites of humans or of animals with zoonotic potential was 75.7 percent (84 out of 111) in Faxinal and 96.2 percent (127 out of 132) in Ivaí. The most prevalent parasites were Ascaris spp., Isospora spp., and Toxocara spp. Positive statistical associations were observed between the number of parasitic forms per domicile and the following variables: time of year (season), the presence of bathrooms in the domicile, and the presence of excrement on peridomiciliar soil. CONCLUSIONS: The high level of soil contamination in Faxinal and Ivaí 1) constitutes a potential source of parasitic infection and 2) suggests that the treatment of human and animal excreta continues to be inadequate.


OBJETIVOS: Determinar: 1) el grado de contaminación parasitaria del suelo; 2) la prevalencia de muestras contaminadas; 3) el número general de formas parasitarias, en función de la distancia entre el sitio donde se tomaron las muestras y el domicilio; 4) el número promedio de formas parasitarias por área peridomiciliar y 5) las variables relacionadas con el número total de formas parasitarias. MÉTODOS: Se recogieron muestras del suelo de los alrededores de 18 (de una muestra total de 63) y 22 domicilios (de una muestra total de 190) situados en los territorios indígenas Faxinal e Ivaí, respectivamente, entre marzo del 2005 y octubre del 2006. Las muestras se evaluaron mediante los métodos propuestos por Baermann, Faust et al. (modificado) y Lutz. RESULTADOS: La prevalencia general de las muestras contaminadas por enteroparásitos humanos o animales que se consideraron de potencial zoonótico fue de 75,7 por ciento (84 de 111) en Faxinal y de 96,2 por ciento (127 de 132) en Ivaí. Las especies de parásitos más prevalentes fueron Ascaris, Isospora y Toxocara. Se observó una asociación estadística positiva entre el número de formas parasitarias halladas en los alrededores de cada domicilio y las siguientes variables: la época del año (estación), la existencia de baños domiciliarios y el hallazgo de excremento en el suelo peridomiciliar. CONCLUSIONES: La gran contaminación del suelo hallada en Faxinal e Ivaí constituye una posible fuente de infección parasitaria e indica que sigue siendo insuficiente el tratamiento de los excrementos de seres humanos y animales.


Subject(s)
Humans , Animals , Parasites/isolation & purification , Soil Microbiology , Animals, Domestic/parasitology , Brazil/epidemiology , Feces/parasitology , Helminthiasis/epidemiology , Helminthiasis/prevention & control , Helminthiasis/transmission , Housing , Hygiene , Indians, South American , Intestinal Diseases, Parasitic/epidemiology , Intestinal Diseases, Parasitic/prevention & control , Intestinal Diseases, Parasitic/transmission , Intestinal Diseases, Parasitic/veterinary , Parasitic Diseases, Animal/epidemiology , Parasitic Diseases, Animal/prevention & control , Parasitic Diseases, Animal/transmission , Prevalence , Protozoan Infections/epidemiology , Protozoan Infections/prevention & control , Protozoan Infections/transmission , Sanitary Engineering
6.
J. bras. med ; 94(1/2): 55-58, jan.-fev. 2008. ilus
Article in Portuguese | LILACS | ID: lil-545610

ABSTRACT

A infecção por Entamoeba histolytica, identificada há mais de 130 anos por Fedor A. Lesh, existe praticamente em todo o mundo e é hoje considerada uma DST - com relação à transmissão é a doença dos cinco efes: finger, feces, flies, fomites e fornication. A epidemiologia da amebíase na cidade do Rio de Janeiro (Brasil), estudada por um de nós (R.M.), parece confirmar o lugar de infecção no rol das doenças sexualmente transmissíveis. Epidemiologia é o estudo da ocorrência de uma doença - estudos epidemiológicos podem influenciar a vida de populações inteiras. O estudo de Framingham (EUA), a investigação de Sharr sobre a doença dos legionários e o trabalho de John Snow sobre a cólera são exemplos clássicos de estudos epidemiológicos que mudaram o comportamento e estilos de vida.


Entamoeba histolytica infection was identified more than 130 years ago, has worldwide occurrence and nowadays is considered a sexually transmitted disease (STD). Regarding transmission is considered as the five Fs disease: finger, feces, flies, fomites and fornication. Rio de Janeiro city amebiasis epidemiology was studied by one of us and seems to confirm its place on STD list. Epidemiology consists on the study of the disease occurrence - epidemiological studies can influence an entire population life. Framinghan (EUA), Legionnaire's disease Sharr investigation and John Snow cholera study are classic examples of epidemiological studies that changed behaviour and lifestyle.


Subject(s)
Male , Female , Amebiasis/diagnosis , Amebiasis/epidemiology , Amebiasis/physiopathology , Amebiasis/transmission , Sexually Transmitted Diseases/transmission , Entamoeba histolytica/pathogenicity , Intestinal Diseases, Parasitic/transmission , Homosexuality, Male , Protozoan Infections/diagnosis , Protozoan Infections/etiology , Protozoan Infections/transmission , Prevalence
7.
PLoS clin. trials ; 1(5): 1-10, Maio. 2006. ilus, graf
Article in English | RSDM | ID: biblio-1531996

ABSTRACT

The candidate malaria vaccine RTS,S/AS02A is a recombinant protein containing part of the circumsporozoite protein (CSP) sequence of Plasmodium falciparum, linked to the hepatitis B surface antigen and formulated in the proprietary adjuvant system AS02A. In a recent trial conducted in children younger than age five in southern Mozambique, the vaccine demonstrated significant and sustained efficacy against both infection and clinical disease. In a follow-up study to the main trial, breakthrough infections identified in the trial were examined to determine whether the distribution of csp sequences was affected by the vaccine and to measure the multiplicity of infecting parasite genotypes. Design: P. falciparum DNA from isolates collected during the trial was used for genotype studies. Setting: The main trial was carried out in the Manhiça district, Maputo province, Mozambique, between April 2003 and May 2004. Participants: Children from the two cohorts of the main trial provided parasite isolates as follows: children from Cohort 1 who were admitted to hospital with clinical malaria; children from Cohort 1 who were parasite-positive in a cross-sectional survey at study month 8.5; children from Cohort 2 identified as parasite-positive during follow-up by active detection of infection. Outcome: Divergence of DNA sequence encoding the CSP T cell-epitope region sequence from that of the vaccine sequence was measured in 521 isolates. The number of distinct P. falciparum genotypes was also determined. Results: We found no evidence that parasite genotypes from children in the RTS,S/AS02A arm were more divergent than those receiving control vaccines. For Cohort 1 (survey at study month 8.5) and Cohort 2, infections in the vaccine group contained significantly fewer genotypes than those in the control group, (p = 0.035, p = 0.006), respectively, for the two cohorts. This was not the case for children in Cohort 1 who were admitted to hospital (p = 0.478). Conclusions: RTS,S/AS02A did not select for genotypes encoding divergent T cell epitopes in the C-terminal region of CSP in this trial. In both cohorts, there was a modest reduction in the mean number of parasite genotypes harboured by vaccinated children compared with controls, but only among those with asymptomatic infections.


Subject(s)
Humans , Child , Malaria Vaccines/immunology , Parasites/parasitology , Protozoan Infections/transmission , T-Lymphocytes/immunology , Cells , Malaria, Falciparum/diagnosis , Malaria, Falciparum/prevention & control , Malaria, Falciparum/transmission , Malaria , Mozambique
8.
Acta cir. bras ; 20(supl.1): 262-265, 2005.
Article in Portuguese | LILACS | ID: lil-474157

ABSTRACT

PURPOSE: There are several ways to propagation of parasitary diseases and how there aren't many bibliographic work about this theme, it was realized a study near to the Natal-RN population, to verify the enteroparasites transmission through the paper money. METHODS: In the Laboratório Parasitologia Clínica was analysed 500 bills of several worths gotten in shops and, concomitantly it was examined samples of a water got from the washed hands of the people who held the money. The methods to realize the parasitologic exams were: Ritchie and Faust et al. RESULTS: It was observed the following parasites prevalent in 48 (9.6%) examined bills: Endolimax nana 31 (6.2%), Entamoeba coli 06 (1.2%), Entamoeba histolytica 01 (0.2%), Ascaris lumbricoides 10 (2.0%). In the water, it vas observed that 40 (40.0%) of them had the same kinds of parasites in their hands. CONCLUSIONS: Finally, it is postulated that the paper money is important to the enteroparasites transmission and it is suggested that new researches must be done in this area.


Subject(s)
Animals , Ascaris lumbricoides/isolation & purification , Intestinal Diseases, Parasitic/transmission , Protozoan Infections/transmission , Paper , Disease Reservoirs/parasitology , Tubulina/isolation & purification , Ascariasis/transmission , Dysentery, Amebic/transmission , Endolimax/isolation & purification , Entamoebiasis/transmission , Entamoeba/isolation & purification , Statistics, Nonparametric
9.
Brasília; s.n; 2000. 101 p. ilus, tab.
Thesis in Portuguese | LILACS | ID: lil-317038

ABSTRACT

As infecções causadas por protozoários da Ordem cinetoplastida, Trypanosoma Cruzi, Leishemania chagasi e Leishemania braziliensis são enzooticas nos trópicos, em cuja floresta úmida encontra-se abundância de reservatórios mamíferos, vetores e ecótopos naturais onde são observados os elos da cadeia de transmissão...


Subject(s)
Humans , Animals , Male , Adult , Protozoan Infections/transmission , Kinetoplastida , Vector Control of Diseases , Brazil , Chagas Disease/transmission , Leishmania braziliensis , Leishmania infantum , Trypanosoma cruzi
10.
J. pediatr. (Rio J.) ; 73(1): 21-5, jan.-fev. 1997. tab
Article in Portuguese | LILACS | ID: lil-199615

ABSTRACT

Objetivo: Devido à alta prevalência das enteroparasitoses entre crianças no Brasil e do possível envolvimento de objetos na transmissäo dessas doenças, foi desenvolvido um estudo para pesquisar a presença de cistos de protozoários, larvas e ovos de helmintos em chupetas. Métodos: No período de março a dezembro de 1993, foram examinadas 86 chupetas de crianças na faixa etária de zero a sete anos, residentes no bairro Vila Promessa, município de Alfenas, MG. A pesquisa de cistos, larvas e ovos foi realizada através do exame microscópico do sedimento obtido da centrifugaçäo do líquido resultante da lavagem das chupetas. Os resultados obtidos foram avaliados empregando-se a análise percentual. Paralelamente aos exames, foram realizadas entrevistas com os responsáveis pela criança...


Subject(s)
Humans , Infant, Newborn , Infant , Child, Preschool , Child , Eukaryota/isolation & purification , Helminths/isolation & purification , Protozoan Infections/transmission , Parasite Egg Count , Sucking Behavior , Ancylostomatoidea/parasitology , Ascaris lumbricoides/parasitology , Enterobius/parasitology , Infant Care
11.
Bol. chil. parasitol ; 50(3/4): 101-2, oct.-dic. 1995. ilus
Article in Spanish | LILACS | ID: lil-173157

ABSTRACT

This is the first report of henneguya sp, a myxozoan parasite of fishes, in faeces of phalacrocorax olivaceus, a piscivorous bird, from Valdivia river, Chile. Phalacrocorax olivaceus would be a mechanical vector of henneguya sp an contributes to diseminate the infection in fishes


Subject(s)
Animals , Birds/parasitology , Disease Vectors , Eukaryota/isolation & purification , Ecosystem , Eukaryota/pathogenicity , Feces/parasitology , Fish Diseases/transmission , Microscopy , Parasite Egg Count , Protozoan Infections/transmission , Spores/isolation & purification , Spores/pathogenicity
15.
Rev. biol. trop ; 35(1): 21-4, jun. 1987. ilus
Article in Spanish | LILACS | ID: lil-103723

ABSTRACT

Se describen formas quísticas de Tritrichomonas muris tal y como se observan a fresco, teñidas con hematoxilina y en preparaciones estudiadas al microscopio electrónico. Se comenta la importancia del hallazgo desde los puntos vista biológico y epidemiológico


Subject(s)
Female , Male , Mice , Cricetinae , Intestinal Diseases, Parasitic/transmission , Protozoan Infections/transmission , Tritrichomonas/ultrastructure , Feces/parasitology , Mesocricetus , Tritrichomonas/growth & development
SELECTION OF CITATIONS
SEARCH DETAIL