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Revista Do Instituto de Medicina... 2002
Topics: Animals; Antibodies, Helminth; Ascaris lumbricoides; Epitopes; Hemagglutination Inhibition Tests; Organ Specificity
PubMed: 12048551
DOI: 10.1590/s0036-46652002000200012 -
Parasitology Oct 2009Ascaris lumbricoides, the human roundworm, is a remarkably infectious and persistent parasite. It is a member of the soil-transmitted helminths or geohelminths and... (Review)
Review
Ascaris lumbricoides, the human roundworm, is a remarkably infectious and persistent parasite. It is a member of the soil-transmitted helminths or geohelminths and infects in the order of 1472 million people worldwide. Despite, its high prevalence and wide distribution it remains along with its geohelminth counterparts, a neglected disease. Ascariasis is associated with both chronic and acute morbidity, particularly in growing children, and the level of morbidity assessed as disability-adjusted life years is about 10.5 million. Like other macroparasite infections, the frequency distribution of A. lumbricoides is aggregated or overdispersed with most hosts harbouring few or no worms and a small proportion harbouring very heavy infections. Furthermore, after chemotherapeutic treatment, individuals demonstrate consistency in the pattern of re-infection with ascariasis, described as predisposition. These epidemiological phenomena have been identified, in a consistent manner, from a range of geographical locations in both children and adults. However, what has proved to be much more refractory to investigation has been the mechanisms that contribute to the observed epidemiological patterns. Parallel observations utilizing human subjects and appropriate animal model systems are essential to our understanding of the mechanisms underlying susceptibility/resistance to ascariasis. Furthermore, these patterns of Ascaris intensity and re-infection have broader implications with respect to helminth control and interactions with other important bystander infections.
Topics: Adult; Age Factors; Animals; Ascariasis; Ascaris; Ascaris lumbricoides; Child; Disease Susceptibility; Humans
PubMed: 19450374
DOI: 10.1017/S0031182009005952 -
Acta Medica Okayama Oct 2008In the present study, we examined the dynamic of school-health-based parasite control and the related socio-economic influences. This is an ecological study based on...
In the present study, we examined the dynamic of school-health-based parasite control and the related socio-economic influences. This is an ecological study based on data from 46 prefectures in Japan. The exponential decay of Ascaris lumbricoides prevalence was calculated by iterative least-squares method. Pearson's correlation and multiple linear regression model analysis were performed to assess the associations between the prevalence of Ascaris lumbricoides in Japanese school children and socio-economic variables such as the prefecture income per capita, the percentage of primary industry, the population density per 1 km2, the diffusion rate of population under water supply, and the percentage of upper secondary school enrollment. The results indicated that the parasite carrier rate was higher in younger students. The half-life of Ascaris lumbricoides prevalence was approximately 3 years with significant variation among prefectures. Multiple regression analyses showed that the decrease of infection in elementary and lower secondary school children had a significant positive association with primary industry and a significant negative association with prefecture income per capita. The school-health-based parasite intervention differs by prefecture and has changed over time according to the respective prefectural stage of economic development.
Topics: Adolescent; Animals; Ascariasis; Ascaris lumbricoides; Child; Child, Preschool; Female; Humans; Japan; Male; Prevalence; Regression Analysis; Socioeconomic Factors
PubMed: 18985090
DOI: 10.18926/AMO/30970 -
Zeitschrift Fur Parasitenkunde (Berlin,... Mar 1965
Topics: Animals; Ascariasis; Ascaris; Ascaris lumbricoides; Ascomycota; Bulgaria; Ecology; Mice; Research; Sheep; Sheep, Domestic
PubMed: 14272961
DOI: 10.1007/BF00329588 -
Revista de Saude Publica Feb 2002To estimate risk areas for Ascaris lumbricoides parasitic overload, using geoprocessing and geostatistic methods of analysis.
OBJECTIVE
To estimate risk areas for Ascaris lumbricoides parasitic overload, using geoprocessing and geostatistic methods of analysis.
METHODS
A coproparasitologic and domiciliary survey was conducted in 19 selected census districts of the state of Rio de Janeiro, Brazil. A sample of 1,664 children aged between 1 - 9 years was selected and plotted in their own home' centroid. Geostatistics techniques allowed spatial exploratory analysis, variographic study, and ordinary kriging. Student t-test, odds ratio and confidence intervals were used in the statistical analysis.
RESULTS
A prevalence of 27.5% was found for A. lumbricoides. Household income, housewife's education level and peridomiciliary conditions were identified as significantly associated factors to the occurrence of ascariasis. An isotropic spherical semivariogram model with 150-m reach, contribution of 0.45 and nugget effect of 0.55 was employed in ordinary kriging.
CONCLUSIONS
Peridomiciliary impact on ascariasis is confirmed by a spatial continuity of 150 m. Disease occurrence could be estimated in the study area and a risk map elaborated using ordinary kriging.
Topics: Animals; Ascariasis; Ascaris lumbricoides; Brazil; Child; Child, Preschool; Educational Status; Environment; Humans; Infant; Parasite Egg Count; Prevalence; Residence Characteristics; Risk Assessment; Sanitation; Socioeconomic Factors
PubMed: 11887232
DOI: 10.1590/s0034-89102002000100011 -
Revista Do Instituto de Medicina... 2009Sialic acid is responsible for the negative charge of the erythrocyte. The decrease of sialic acid has hemodynamical and hemorheological importance. The aim was to study...
Sialic acid is responsible for the negative charge of the erythrocyte. The decrease of sialic acid has hemodynamical and hemorheological importance. The aim was to study the effect of A. lumbricoides on the erythrocyte superficial charge using the Partition Method in aqueous two-phase system in order to indirectly evaluate the alteration of sialic acid in the red cells. We worked with five parasite extracts (AE) and larvae concentrate (LC). Erythrocyte superficial charge was studied by working with non-treated (Controls) and treated erythrocytes. The treatment consisted of incubating the erythrocytes with AE or LC for 30 minutes at 4 degrees C, 20 degrees C and 37 degrees C. The red cells were separated in a sensitive charge two-phase system (Dx/ PEG). The partition coefficient (P) of treated and untreated erythrocytes were calculated. The results showed a P decrease at the three temperatures for red cells treated with four of the AE. The remaining extract did change P values at any of the temperatures studied. The erythrocytes treated with LC showed a decrease in the P value at 37 degrees C and 4 degrees C but no change was observed at 25 degrees C. Statistical analysis concluded that P values were significantly lower in treated erythrocytes than in their corresponding untreated ones (p < 0.05). The Partition Method showed that this parasite alters the erythrocyte superficial charge which may indicate that it can catch sialic acid.
Topics: Animals; Ascaris lumbricoides; Cell Separation; Erythrocyte Membrane; Erythrocytes; Membrane Potentials; Models, Biological; N-Acetylneuraminic Acid; Osmolar Concentration
PubMed: 19739003
DOI: 10.1590/s0036-46652009000400008 -
Parasitology Dec 1998This paper describes the distribution of Ascaris suum in experimentally and naturally infected pigs, and offers a comparison with A. lumbricoides infections in humans.... (Comparative Study)
Comparative Study
This paper describes the distribution of Ascaris suum in experimentally and naturally infected pigs, and offers a comparison with A. lumbricoides infections in humans. In the first study, worms were recovered post-mortem from a group of 38 pigs that had been trickle inoculated with 10,000 infective A. suum eggs twice weekly for 12 weeks. In the second study, worms were collected from a group of 49 pigs that had been kept on a pasture contaminated with infective A. suum eggs for 10 weeks, after which they received treatment with an anthelmintic; they then were turned out on the same pasture for a second 10-week period before slaughter. The worm burdens of the naturally infected pigs were recorded both at treatment and post-mortem. Mean worm counts were similar at all occasions but the prevalence of infection was higher in the trickle infected and naturally reinfected pigs. Furthermore, the prevalence in naturally infected pigs increased significantly over the study period. Worm burden distributions in all groups were heavily overdispersed, but the distribution patterns differed significantly between groups: lower exposure (initial natural infection) gave a low prevalence and an almost uniform distribution of worm burdens among infected hosts. Continued or higher exposure (trickle and natural reinfection) resulted in increased prevalence and a reduction in the proportion of hosts with increasing worm load. A positive correlation was found between initial and reinfection worm burdens in the naturally infected pig population, suggesting that individual pigs are predisposed to a high or low intensity of infection. The prevalence and intensity as well as the distribution observed for A. suum infection in pigs were comparable to those reported for A. lumbricoides in endemic areas, and there is evidence for predisposition to A. suum in pigs, with an estimated correlation coefficient similar to that found in humans. It is concluded that A. suum infections in pigs are a suitable model to study the population dynamics of A. lumbricoides in human populations.
Topics: Administration, Oral; Animals; Antinematodal Agents; Ascariasis; Ascaris lumbricoides; Ascaris suum; Feces; Humans; Male; Parasite Egg Count; Piperazine; Piperazines; Prevalence; Specific Pathogen-Free Organisms; Swine; Swine Diseases
PubMed: 9881384
DOI: 10.1017/s0031182098003382 -
The American Journal of Tropical... Jun 1999Epidemiologic studies of helminthic infections have shown that susceptibility to these parasites frequently aggregates in families, suggesting the possible involvement...
Epidemiologic studies of helminthic infections have shown that susceptibility to these parasites frequently aggregates in families, suggesting the possible involvement of genetic factors. This paper presents a genetic epidemiologic analysis of Ascaris lumbricoides infection in the Jirel population of eastern Nepal. A total of 1,261 individuals belonging to a single pedigree were assessed for intensity of Ascaris infection at two time points. Following an initial assessment in which all individuals were treated with albendazole, a follow-up examination was performed one year later to evaluate reinfection patterns. Three measures of worm burden were analyzed, including eggs per gram of feces, direct worm counts, and worm biomass (weight). For all traits, variance component analysis of the familial data provided unequivocal evidence for a strong genetic component accounting for between 30% and 50% of the variation in worm burden. Shared environmental (i.e., common household) effects account for between 3% and 13% of the total phenotypic variance.
Topics: Adolescent; Adult; Age Distribution; Aged; Aged, 80 and over; Animals; Ascariasis; Ascaris lumbricoides; Child; Child, Preschool; Family; Feces; Female; Genetic Predisposition to Disease; Humans; Longitudinal Studies; Male; Middle Aged; Nepal; Parasite Egg Count; Pedigree; Prevalence; Sex Distribution
PubMed: 10403321
DOI: 10.4269/ajtmh.1999.60.921 -
The Antiseptic Mar 1948
Topics: Animals; Ascariasis; Ascaris lumbricoides; Humans
PubMed: 18912679
DOI: No ID Found -
Digestive and Liver Disease : Official... Mar 2018
Topics: Adult; Aged; Animals; Ascariasis; Ascaris lumbricoides; Capsule Endoscopy; Gastrointestinal Hemorrhage; Humans; Male
PubMed: 29126645
DOI: 10.1016/j.dld.2017.10.016