967 resultados para Hôte-parasite
Resumo:
In order to better understand the biology of Centrocestus formosanus in a definitive host model, mice of Swiss and AKR/J strains were experimentally infected with 100 metacercariae of the parasite. Fourteen days post-infection, the rodents were killed and adult trematodes were recovered from the small intestine. The percentage of parasite recovery from AKR/J mice (11.4%) was significantly higher than that from Swiss mice (5.3%). Moreover, trematodes recovered from the AKR/J strain were more developed and had greater fecundity. Peculiarities concerning the mice’s immune system could explain the difference in susceptibility and in worm development seen in the present study. The data obtained confirm that mice are susceptible to infection with C. formosanus and indicate that the AKR/J strain provides a more favorable environment for parasite development.
Resumo:
The aim of this study was to determine the occurrence of intestinal parasites in a quilombola community from the northern Espírito Santo, Brazil. Descendants of slaves who arrived in Brazil in the sixteenth century, this population settled in the municipality of São Mateus in 1858. Fresh fecal samples from 82 individuals who agreed to participate in the study were collected between August 2009 and July 2010, and immediately sent to the Clinical Laboratory of the Centro Universitário Norte do Espírito Santo of the Universidade Federal do Espírito Santo for analysis. Out of all the participants, 36 (43.9%) were male and 46 (56.1%) were female, whose ages ranged from six to 85 years. The study of the occurrence of intestinal parasites indicated that 35 individuals (42.7%) were infected with at least one intestinal parasite. Among helminths, the most frequent were hookworms, with a rate of 14.6%. With regard to protozoa, Entamoeba coli, Entamoeba histolytica/Entamoeba dispar and Endolimax nana stood out, with frequencies of 23.2%, 8.5% and 4.9%, respectively. The occurrence of biparasitism was observed in 13 of the 82 subjects, accounting for 15.8%, and no cases of multiple parasitic infections were observed. It was concluded that the reduction of cases of intestinal diseases due to parasites will only be achieved with the improvement of basic sanitation and quality of life of quilombola populations.
Resumo:
Enteric parasitosis remains an important public health problem in many areas around the world including in Brazil, and it is frequently associated with poverty and lack of sanitation facilities. Research carried out over the course of a year revealed that 96.6% (28/29) of children randomly selected from a 'landless farm workers' settlement in Araras, São Paulo, aged 4 - 15 years, presented Giardia intestinalis cysts. After referral to the neighborhood Health Office, all the children received tinidazole, given as a single dose of 50 mg/kg and 12 months later, new fecal samples were collected and analyzed. Despite the low adherence to the study, a high percentage (64.3% - 9/14) of the children remained positive for the parasite. This study showed a high positivity of giardiasis in child residents of the settlement, even after treatment; adults were not sensitized to the study and did not collected and/or deliver children fecal samples. The precarious living conditions are consistent with a high susceptibility to parasitic diseases, suggesting that the treatment of the infected individuals without identifying and eradicating the means of contamination is simply a palliative measure.
Resumo:
In Colombia, pentavalent antimonials and miltefosine are the drugs of choice for the treatment of cutaneous leishmaniasis; however, their toxicity, treatment duration, (treatment adherence problems), cost, and decreased parasite sensitivity make the search for alternative treatments of American cutaneous leishmaniasis necessary. Based on the results found in a controlled, open, randomized, phase III clinical trial, the efficacy and safety of miltefosine was compared to that of thermotherapy for the treatment of cutaneous leishmaniasis in Colombia. Adult patients from the Colombian army participated in the study; they received either 50 mg of miltefosine three times per day for 28 days by the oral route (n = 145) or a thermotherapy (Thermomed®) application of 50 °C for 30 seconds over the lesion and surrounding area (n = 149). Both groups were comparable with respect to their sociodemographic, clinical, and parasitological characteristics. The efficacy of miltefosine by protocol and by intention to treat was 70% (85/122 patients) and 69% (85/145 patients), respectively. The adverse effects were primarily gastrointestinal for miltefosine and pain at the lesion site after treatment for thermotherapy. No statistically significant difference was found in the efficacy analysis (intention to treat and protocol) between the two treatments. ClinicalTrials.gov: NCT00471705.
Resumo:
SUMMARY To evaluate soil contamination by parasites in different developmental stages in public squares used as recreation and leisure areas for children in Belo Horizonte (MG, Brazil), 210 soil samples and 141 canine fecal samples were collected from 42 squares in the city. These samples were analyzed by the Caldwell and Caldwell technique and the Hoffman, Pons, and Janer technique. Of the samples analyzed, 89 (42.4%) soil samples and 104 (73.5%) fecal samples were contaminated with Ancylostoma sp., Toxocara sp., Trichuris sp., or Dipylidium sp. eggs; Giardia sp. cysts; or Isospora sp. oocysts. The commonest parasite was Ancylostoma sp., found in 85% soil and 99% fecal samples, followed by Toxocara sp., found in 43.7% soil and 30.7% fecal samples.
Resumo:
SUMMARY A food-borne trematode infection fascioliasis is one among common public health problems worldwide. It caused a great economic loss for the human race. Control of snail population below a certain threshold level is one of the important methods in the campaign to reduce the incidence of fascioliasis. The life cycle of the parasite can be interrupted by killing the snail or Fasciola larva redia and cercaria inside of the snail Lymnaea acuminata. In vitro toxicity of different binary combinations (1:1 ratio) of plant-derived larvicidal active components such as citral, ferulic acid, umbelliferone, azadirachtin and allicin against Fasciola redia and cercaria were tested. The mortality of larvae was observed at 2h, 4h, 6h and 8h of treatment. In in vitro condition azadirachtin + allicin (1:1 ratio) was highly toxic against redia and cercaria (8h LC50 0.006 and 0.005 mg/L). Toxicity of citral + ferulic acid was lowest against redia and cercaria larvae.
Resumo:
SUMMARY Little is known about the frequency of intestinal parasites in the elderly due to a lack of attention given to the occurrence of these infections among older adults. This study compares the frequency of Strongyloides stercoralis and other enteroparasites between elderly living in nursing homes (n = 100) and those noninstitutionalized (n = 100) from Uberlândia, state of Minas Gerais, southeastern Brazil, associated with data of epidemiological and socio-demographic conditions. Through coproparasitological examination of both groups, enteroparasites were detected in 15 of 200 individuals examined (7.5%; CI: 5.1- 9.9). S. stercoralis was the most frequent parasite 10/200 (5%; CI: 4.2-5.8), being significantly higher in males and in individuals with autonomy for daily living activities. There were no statistical differences in the prevalence of parasites between the two groups compared. In conclusion, S. stercoralis infection was highly prevalent in elderly patients and it does not depend on whether the individual was institutionalized or not.