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1.
PLoS One ; 17(1): e0262361, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34990483

RESUMO

BACKGROUND: Rwanda is a sub-Saharan country, where intestinal parasite infections, anemia and undernutrition coexist. The purpose of this research is to study the relationship between intestinal parasite infections and undernutrition/anemia to clarify the priorities of intervention in the rural area of Gakenke district in the Northern Province of Rwanda. MATERIALS AND METHODS: A total of 674 students from Nemba I School, participated in a cross-sectional study, in which their parasitological and nutritional status were analysed. Statistical analysis was performed by χ2 test, univariate analysis and Odds ratios (OR). RESULTS: A total of 95.3% of children presented intestinal parasitism, most of whom (94.5%) infected by protozoa and 36.1% infected by soil-transmitted helminths (STH), with Trichuris trichiura (27.3%) being the most prevalent. Multiple infections were found to be high (83.8%), with protozoa and STH co-infections in 30.6%. STH infections were mainly of low/moderate intensity. Neither infection nor STH infection of any intensity profile, was significantly related to anemia. In addition, STH infection, regardless of the intensity profile, was not associated with stunting, underweight or thinness. There was no difference between genders nor among ages in odds of anemia and nutritional status in STH-infected schoolchildren. CONCLUSION: Multiparasitism remains high among Rwandan schoolchildren and is likely to cause nutritional problems. This work emphasizes the importance of keeping up health programs to reduce the prevalence of infection.


Assuntos
Anemia/epidemiologia , Desnutrição/epidemiologia , Adolescente , Animais , Criança , Pré-Escolar , Estudos Transversais , Fezes/parasitologia , Feminino , Transtornos do Crescimento/epidemiologia , Transtornos do Crescimento/parasitologia , Helmintíase/epidemiologia , Helmintos/patogenicidade , Humanos , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Masculino , Estado Nutricional/fisiologia , Prevalência , Ruanda/epidemiologia , Solo/parasitologia , Magreza/epidemiologia , Magreza/parasitologia , Tricuríase/epidemiologia , Trichuris/patogenicidade
2.
Front Immunol ; 12: 627638, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33936040

RESUMO

Background: Tuberculosis (TB) is still a major challenge for humankind. Because regions with the highest incidence also have a high prevalence of helminthiasis and nutritional scarcity, we wanted to understand the impact of these on TB progression. Methods: We have developed an experimental murine model for active TB in C3HeB/FeJ, coinfected with Trichuris muris and Heligmosomoides polygyrus nematodes, and exposed to an environmental mycobacterium (M. manresensis) and intermittent fasting. Cause-effect relationships among these factors were explored with Partial Least Squares Path modelling (PLSPM). Results: Previous parasitization had a major anti-inflammatory effect and reduced systemic levels of ADA, haptoglobin, local pulmonary levels of IL-1ß, IL-6, TNF-α, CXCL-1, CXCL-5 and IL-10. Oral administration of heat-killed M. manresensis resulted in a similar outcome. Both interventions diminished pulmonary pathology and bacillary load, but intermittent food deprivation reduced this protective effect increasing stress and inflammation. The PLSPM revealed nematodes might have protective effects against TB progression. Conclusions: Significantly higher cortisol levels in food-deprivation groups showed it is a stressful condition, which might explain its deleterious effect. This highlights the impact of food security on TB eradication policies and the need to prioritize food supply over deworming activities.


Assuntos
Coinfecção , Privação de Alimentos , Helmintíase/parasitologia , Enteropatias Parasitárias/parasitologia , Pulmão/microbiologia , Mycobacterium tuberculosis/patogenicidade , Nematospiroides dubius/patogenicidade , Infecções por Strongylida/parasitologia , Tricuríase/parasitologia , Trichuris/patogenicidade , Tuberculose Pulmonar/microbiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Feminino , Helmintíase/imunologia , Helmintíase/metabolismo , Interações Hospedeiro-Parasita , Mediadores da Inflamação/metabolismo , Enteropatias Parasitárias/imunologia , Enteropatias Parasitárias/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Masculino , Camundongos Endogâmicos C3H , Mycobacterium tuberculosis/imunologia , Nematospiroides dubius/imunologia , Estado Nutricional , Infecções por Strongylida/imunologia , Infecções por Strongylida/metabolismo , Tricuríase/imunologia , Tricuríase/metabolismo , Trichuris/imunologia , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/metabolismo
3.
PLoS One ; 16(4): e0240872, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33882065

RESUMO

Social grooming in the animal kingdom is common and serves several functions, from removing ectoparasites to maintaining social bonds between conspecifics. We examined whether time spent grooming with others in a highly social mammal species was associated with infection status for gastrointestinal parasites. Of six parasites detected, one (Trichuris sp.) was associated with social grooming behaviors, but more specifically with direct physical contact with others. Individuals infected with Trichuris sp. spent significantly less time grooming conspecifics than those not infected, and time in direct contact with others was the major predictor of infection status. One model correctly predicted infection status for Trichuris sp. with a reliability of 95.17% overall when the variables used were time spent in direct contact and time spent grooming others. This decrease in time spent grooming and interacting with others is likely a sickness behavior displayed by individuals with less energy or motivation for non-essential behaviors. This study emphasizes the possible links between host behavior and parasitic infections and highlights the need for an understanding of a study population's parasitic infections when attempting to interpret animal behavior.


Assuntos
Comportamento Animal/fisiologia , Chlorocebus aethiops/fisiologia , Chlorocebus aethiops/parasitologia , Trichuris/patogenicidade , Animais , Criança , Pré-Escolar , Feminino , Asseio Animal/fisiologia , Humanos , Lactente , Enteropatias Parasitárias/parasitologia , Enteropatias Parasitárias/fisiopatologia , Masculino , Reprodutibilidade dos Testes , Comportamento Social , Tricuríase/fisiopatologia
4.
PLoS One ; 15(12): e0243946, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33320918

RESUMO

BACKGROUND: Soil-transmitted helminths (STH), i.e., Ascaris lumbricoides, Trichuris trichiura and hookworms are among the most prevalent Neglected Tropical Diseases (NTDs) in Ethiopia. Although pre-school aged children pay a high morbidity toll associated with STH infections, evidence on prevalence, intensity and intervention status is lacking in Ethiopia. This study, therefore, aimed to address these gaps to inform decision made on STH. METHODS: We did a community-based cross-sectional study in five districts of Gamo Gofa zone, Southern Ethiopia; in January 2019. Data were collected using pre-tested questionnaire, and the Kato-Katz technique was used to diagnose parasites eggs in stool. Then, collected data were edited and entered into EpiData 4.4.2, and exported to SPSS software (IBM, version 25) for analysis. RESULTS: A total of 2462 PSAC participated in this study. Overall, the prevalence of STH was 23.5% (578/2462) (95% confidence interval (CI) = 21.8%-25.2%). As caris lumbricoides was the most prevalent (18.6%), followed by Trichuris trichiura (9.2%), and hookworms (3.1%). Of the total, 7.4% PSAC were infected with two STH species. Most of the positive cases with STH showed low infection intensities, while 15.1% ascariasis cases showed moderate infection intensities. The study found that 68.7% of PSAC were treated with albendazole. Also, household's level data showed that 39.4% used water from hand-dug well; 52.5% need to travel ≥30 minutes to collect water; 77.5% did not treat water, and 48.9% had no hand washing facility. In addition, almost 93% care givers achieved less than the mean knowledge and practice score (≤5) on STH prevention. CONCLUSIONS: This study showed that significant proportions of pre-school aged children are suffering from STH infections despite preventive chemotherapy exist at the study area. Also, gaps in the interventions against STH were highlighted. Thus, a call for action is demanding to eliminate STH among PSAC in Ethiopia by 2030.


Assuntos
Ascaríase/transmissão , Helmintíase/transmissão , Solo/parasitologia , Tricuríase/transmissão , Adolescente , Idoso , Ancylostomatoidea/patogenicidade , Animais , Ascaríase/epidemiologia , Ascaríase/parasitologia , Ascaríase/prevenção & controle , Ascaris lumbricoides/patogenicidade , Criança , Pré-Escolar , Estudos Transversais , Etiópia/epidemiologia , Fezes/parasitologia , Feminino , Desinfecção das Mãos , Helmintíase/parasitologia , Helmintíase/patologia , Helmintíase/prevenção & controle , Helmintos/patogenicidade , Humanos , Masculino , Prevalência , Tricuríase/epidemiologia , Tricuríase/parasitologia , Tricuríase/prevenção & controle , Trichuris/patogenicidade
6.
Nat Rev Dis Primers ; 6(1): 44, 2020 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-32467581

RESUMO

Trichuriasis and ascariasis are neglected tropical diseases caused by the gastrointestinal dwelling nematodes Trichuris trichiura (a whipworm) and Ascaris lumbricoides (a roundworm), respectively. Both parasites are staggeringly prevalent, particularly in tropical and subtropical areas, and are associated with substantial morbidity. Infection is initiated by ingestion of infective eggs, which hatch in the intestine. Thereafter, T. trichiura larvae moult within intestinal epithelial cells, with adult worms embedded in a partially intracellular niche in the large intestine, whereas A. lumbricoides larvae penetrate the gut mucosa and migrate through the liver and lungs before returning to the lumen of the small intestine, where adult worms dwell. Both species elicit type 2 anti-parasite immunity. Diagnosis is typically based on clinical presentation (gastrointestinal symptoms and inflammation) and the detection of eggs or parasite DNA in the faeces. Prevention and treatment strategies rely on periodic mass drug administration (generally with albendazole or mebendazole) to at-risk populations and improvements in water, sanitation and hygiene. The effectiveness of drug treatment is very high for A. lumbricoides infections, whereas cure rates for T. trichiura infections are low. Novel anthelminthic drugs are needed, together with vaccine development and tools for diagnosis and assessment of parasite control in the field.


Assuntos
Ascaríase/tratamento farmacológico , Tricuríase/tratamento farmacológico , Animais , Ascaríase/epidemiologia , Ascaríase/fisiopatologia , Ascaris lumbricoides/efeitos dos fármacos , Ascaris lumbricoides/patogenicidade , Humanos , Prevalência , Tricuríase/epidemiologia , Tricuríase/fisiopatologia , Trichuris/efeitos dos fármacos , Trichuris/patogenicidade
7.
PLoS One ; 14(12): e0225142, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800582

RESUMO

Gastrointestinal parasites colonizing the mammalian gut influence the host immune system and health. Parasite infections, mainly helminths, have been studied intensively in both humans and non-human animals, but relatively rarely within a conservation framework. The Udzungwa red colobus monkey (Procolobus gordonorum) is an endangered endemic primate species living in the Udzungwa Mountains of Tanzania, a global biodiversity hotspot. Since this endemic primate species is highly sensitive to human disturbance, here we investigate whether habitat type (driven by natural and human-induced factors) is associated with helminth diversity. Using standard flotation and sedimentation techniques, we analyzed 251 fecal samples belonging to 25 social groups from four different forest blocks within the Udzungwa Mountains. Five parasitic helminth taxa were recovered from Udzungwa red colobus, including Trichuris sp., Strongyloides fulleborni, S. stercoralis, a strongylid nematode and Colobenterobius sp. We used Generalized Linear Mixed Models to explore the contribution of habitat type, altitude and fecal glucocorticoid levels (as biomarkers of stress) in predicting gut parasite variation. Although some parasites (e.g., Trichuris sp.) infected more than 50% of individuals, compared to others (e.g., Colobenterobius sp.) that infected less than 3%, both parasite richness and prevalence did not differ significantly across forests, even when controlling for seasonality. Stress hormone levels also did not predict variation in parasite richness, while altitude could explain it resulting in lower richness at lower altitudes. Because human activities causing disturbance are concentrated mainly at lower altitudes, we suggest that protection of primate forest habitat preserves natural diversity at both macro- and microscales, and that the importance of the latter should not be underestimated.


Assuntos
Altitude , Colobinae/parasitologia , Ecossistema , Estresse Psicológico/parasitologia , Animais , Colobinae/fisiologia , Espécies em Perigo de Extinção , Strongyloides/patogenicidade , Trichuris/patogenicidade
8.
Genes (Basel) ; 10(6)2019 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-31181837

RESUMO

The complete mitochondrial (mt) genome of Trichuris skrjabini has been determined in the current study and subsequently compared with closely related species by phylogenetic analysis based on concatenated datasets of mt amino acid sequences. The whole mt genome of T. skrjabini is circular and 14,011 bp in length. It consists of a total of 37 genes including 13 protein coding genes (PCGs), two ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNAs) genes, and two non-coding regions. The gene arrangement and contents were consistent with other members of the Trichuridae family including Trichuris suis, Trichuris trichiura, Trichuris ovis, and Trichuris discolor. Phylogenetic analysis based on concatenated datasets of amino acids of the 12 PCGs predicted the distinctiveness of Trichuris skrjabini as compared to other members of the Trichuridae family. Overall, our study supports the hypothesis that T. skrjabini is a distinct species. The provision of molecular data of whole mt genome of T. skrjabini delivers novel genetic markers for future studies of diagnostics, systematics, population genetics, and molecular epidemiology of T. skrjabini.


Assuntos
DNA Mitocondrial/genética , Genoma Mitocondrial/genética , Tricuríase/genética , Trichuris/genética , Sequência de Aminoácidos/genética , Animais , Humanos , Anotação de Sequência Molecular , Filogenia , Tricuríase/parasitologia , Trichuris/classificação , Trichuris/patogenicidade
9.
Pak J Pharm Sci ; 32(2 (Supplementary)): 799-803, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31103975

RESUMO

Information on prevalence of soil-transmitted helminth (STH) infections among school children is scarce in Pakistan. This study was aimed to investigate the prevalence of soil-transmitted helminth in school children of three districts in, Khyber Pakhtunkhwa, Pakistan. A total of 300 stool samples were examined from August 2015 to August 2016 using direct smear (Normal saline and Lugol's Iodine solution) and the concentration methods. One hundred and eighty seven (62.3%) pupils were found infected with soil-transmitted helminths. One hundred and forty five (77.5%) were infected with single parasite and forty two (22.4%) with multiple infections. Ascaris lumbricoides 125 (66.4%), Trichuris trichura 50 (26.5%) and Ancylostoma duedenale 13 (6.91%) were detected. The children above 8 years in age were more parasitized than below 8 years (p=0.7832; P>0.05). Males were found more parasitized than females (p=0.9315; P>0.05). Children in lower Dir district were found more infected followed by Swat and upper Dir (P< 0.0001; p<0.05). No significant relationship was found among the examined and that of infected children for ages and sex in all the districts. Malakand division is an area with poor hygiene located in temperate zone near the border of Afghanistan and China. The prevalence of reported nematode parasites here compared with the same studies is unexpectedly high. These types of studies should continue time to time to know the hazardous nature of such parasitic infections for the betterment of the human health.


Assuntos
Helmintíase/epidemiologia , Helmintíase/transmissão , Animais , Ascaríase/epidemiologia , Ascaríase/transmissão , Ascaris lumbricoides/isolamento & purificação , Criança , Coinfecção/epidemiologia , Coinfecção/parasitologia , Estudos Transversais , Fezes/parasitologia , Feminino , Infecções por Uncinaria/epidemiologia , Infecções por Uncinaria/transmissão , Humanos , Masculino , Paquistão/epidemiologia , Prevalência , Microbiologia do Solo , Tricuríase/epidemiologia , Tricuríase/transmissão , Trichuris/isolamento & purificação , Trichuris/patogenicidade
10.
PLoS One ; 14(2): e0211244, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30807587

RESUMO

Expulsion of parasitic gastrointestinal nematodes requires diverse effector mechanisms coordinated by a Th2-type response. The evolutionarily conserved JmjC protein; Myc Induced Nuclear Antigen (Mina) has been shown to repress IL4, a key Th2 cytokine, suggesting Mina may negatively regulate nematode expulsion. Here we report that expulsion of the parasitic nematode Trichuris muris was indeed accelerated in Mina deficient mice. Unexpectedly, this was associated not with an elevated Th2- but rather an impaired Th1-type response. Further reciprocal bone marrow chimera and conditional KO experiments demonstrated that retarded parasite expulsion and a normal Th1-type response both required Mina in intestinal epithelial cells (IECs). Transcriptional profiling experiments in IECs revealed anti-microbial α-defensin peptides to be the major target of Mina-dependent retention of worms in infected mice. In vitro exposure to recombinant α-defensin peptides caused cytotoxic damage to whipworms. These results identify a latent IEC-intrinsic anthelmintic pathway actively constrained by Mina and point to α-defensins as important effectors that together with Mina may be attractive therapeutic targets for the control of nematode infection.


Assuntos
Células Epiteliais/metabolismo , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Trichuris/imunologia , Animais , Citocinas/análise , Células Epiteliais/citologia , Intestinos/citologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Neoplasias/deficiência , Proteínas Nucleares/deficiência , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Células Th1/citologia , Células Th1/imunologia , Células Th1/metabolismo , Células Th2/citologia , Células Th2/imunologia , Células Th2/metabolismo , Transcriptoma , Tricuríase/tratamento farmacológico , Tricuríase/imunologia , Tricuríase/patologia , Trichuris/efeitos dos fármacos , Trichuris/patogenicidade , alfa-Defensinas/genética , alfa-Defensinas/metabolismo
11.
PLoS One ; 13(6): e0197399, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29924800

RESUMO

In this study, we screen archaeological soil samples by microscopy and analyse the samples by next generation sequencing to obtain results with parasites at species level and untargeted findings of plant and animal DNA. Three separate sediment layers of an ancient man-made pond in Hoby, Denmark, ranging from 100 BC to 200 AD, were analysed by microscopy for presence of intestinal worm eggs and DNA analysis were performed to identify intestinal worms and dietary components. Ancient DNA of parasites, domestic animals and edible plants revealed a change in use of the pond over time reflecting the household practice in the adjacent Iron Age settlement. The most abundant parasite found belonged to the Ascaris genus, which was not possible to type at species level. For all sediment layers the presence of eggs of the human whipworm Trichuris trichiura and the beef tapeworm Taenia saginata suggests continuous disposal of human faeces in the pond. Moreover, the continuous findings of T. saginata further imply beef consumption and may suggest that cattle were living in the immediate surrounding of the site throughout the period. Findings of additional host-specific parasites suggest fluctuating presence of other domestic animals over time: Trichuris suis (pig), Parascaris univalens (horse), Taenia hydatigena (dog and sheep). Likewise, alternating occurrence of aDNA of edible plants may suggest changes in agricultural practices. Moreover, the composition of aDNA of parasites, plants and vertebrates suggests a significant change in the use of the ancient pond over a period of three centuries.


Assuntos
DNA Antigo/análise , Parasitos/genética , Análise de Sequência de DNA , Trichuris/genética , Animais , Arqueologia , Bovinos , Dinamarca , Fezes/parasitologia , Cavalos/parasitologia , Humanos , Parasitos/isolamento & purificação , Plantas/genética , Ovinos/parasitologia , Suínos/parasitologia , Trichuris/isolamento & purificação , Trichuris/patogenicidade
12.
Sci Rep ; 8(1): 3782, 2018 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-29491349

RESUMO

Resistance to the intestinal parasitic helminth Trichuris muris requires T-helper 2 (TH2) cellular and associated IgG1 responses, with expulsion typically taking up to 4 weeks in mice. Here, we show that the time-of-day of the initial infection affects efficiency of worm expulsion, with strong TH2 bias and early expulsion in morning-infected mice. Conversely, mice infected at the start of the night show delayed resistance to infection, and this is associated with feeding-driven metabolic cues, such that feeding restriction to the day-time in normally nocturnal-feeding mice disrupts parasitic expulsion kinetics. We deleted the circadian regulator BMAL1 in antigen-presenting dendritic cells (DCs) in vivo and found a loss of time-of-day dependency of helminth expulsion. RNAseq analyses revealed that IL-12 responses to worm antigen by circadian-synchronised DCs were dependent on BMAL1. Therefore, we find that circadian machinery in DCs contributes to the TH1/TH2 balance, and that environmental, or genetic perturbation of the DC clock results in altered parasite expulsion kinetics.


Assuntos
Fatores de Transcrição ARNTL/fisiologia , Ritmo Circadiano , Células Dendríticas/imunologia , Linfonodos/imunologia , Células Th2/imunologia , Tricuríase/imunologia , Trichuris/patogenicidade , Animais , Células Cultivadas , Células Dendríticas/parasitologia , Linfonodos/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Linfócitos T/imunologia , Linfócitos T/parasitologia , Células Th2/parasitologia , Tricuríase/parasitologia
13.
Am J Trop Med Hyg ; 98(2): 570-575, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29260648

RESUMO

The aim of this study was to determine for the first time the prevalence of enteroparasites in preschool children originating from the seven departments of the Pacific region in Nicaragua. One stool sample of each of 1,217 children, from 6 months to 5 years of age, was collected and personal data were recorded on delivery of the container. Samples fixed in 10% formalin were processed by a formol-acetate concentration and a modified Ziehl-Neelsen technique. The overall prevalence of enteroparasite infections was 68.2% with a total of at least 20 species. Blastocystis hominis (45.5%), Giardia intestinalis (31.7%), Trichuris trichiura (8.2%), and Ascaris lumbricoides (5.2%) were the most prevalent protozoa and helminth species in the total study as well as in all departments. Protozoan prevalence presented a statistically significant difference by gender (male: 69.6%; female: 46.7%; P < 0.001), and males presented a higher T. trichiura infection rate than females (male: 9.9%; female 6.4%; P < 0.035). Protozoan prevalence increased with age with a statistically significant difference (P < 0.001). Helminths were always more prevalent in urban areas (P < 0.0002). Protozoan infections result statistically higher than helminth infections so that water-based transmission could be suspected. Based on the differences with respect to species and parasite prevalence between the seven departments in the Pacific region of Nicaragua, the exploration of local factors associated with the transmission of enteroparasites should also be considered to reduce infection.


Assuntos
Helmintíase/complicações , Tricuríase/complicações , Animais , Ascaris lumbricoides/parasitologia , Ascaris lumbricoides/patogenicidade , Pré-Escolar , Fezes/parasitologia , Feminino , Helmintíase/epidemiologia , Helmintos/parasitologia , Helmintos/patogenicidade , Humanos , Lactente , Masculino , Nicarágua/epidemiologia , Prevalência , População Rural , Tricuríase/epidemiologia , Trichuris/parasitologia , Trichuris/patogenicidade
14.
PLoS Negl Trop Dis ; 11(6): e0005708, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28650985

RESUMO

Incidences of infection-related cancers are on the rise in developing countries where the prevalence of intestinal nematode worm infections are also high. Trichuris muris (T. muris) is a murine gut-dwelling nematode that is the direct model for human T. trichiura, one of the major soil-transmitted helminth infections of humans. In order to assess whether chronic infection with T. muris does indeed influence the development of cancer hallmarks, both wild type mice and colon cancer model (APC min/+) mice were infected with this parasite. Parasite infection in wild type mice led to the development of neoplastic change similar to that seen in mice that had been treated with the carcinogen azoxymethane. Additionally, both chronic and acute infection in the APCmin/+ mice led to an enhanced tumour development that was distinct to the site of infection suggesting systemic control. By blocking the parasite induced T regulatory response in these mice, the increase in the number of tumours following infection was abrogated. Thus T. muris infection alone causes an increase in gut pathologies that are known to be markers of cancer but also increases the incidence of tumour formation in a colon cancer model. The influence of parasitic worm infection on the development of cancer may therefore be significant.


Assuntos
Proteína da Polipose Adenomatosa do Colo/deficiência , Proteína da Polipose Adenomatosa do Colo/metabolismo , Carcinogênese , Neoplasias do Colo/epidemiologia , Tricuríase/complicações , Trichuris/patogenicidade , Proteína da Polipose Adenomatosa do Colo/genética , Animais , Doença Crônica , Neoplasias do Colo/etiologia , Modelos Animais de Doenças , Incidência , Camundongos
15.
PLoS One ; 12(4): e0175137, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28384306

RESUMO

BACKGROUND: The intestinal nematode Trichuris trichiura is among the most common causes of human infectious disease worldwide. As for other soil-transmitted nematodes, its reproductive success and thus prevalence and intensity of infection in a given area strongly depend on environmental conditions. Characterization of the influence of environmental factors can therefore aid to identify infection hot spots for targeted mass treatment. METHODOLOGY: We analyzed data from a cross-sectional survey including 6234 participants from nine distinct study sites in Mbeya region, Tanzania. A geographic information system was used to combine remotely sensed and individual data, which were analyzed using uni- and multivariable Poisson regression. Household clustering was accounted for and when necessary, fractional polynomials were used to capture non-linear relationships between T. trichiura infection prevalence and environmental variables. PRINCIPAL FINDINGS: T. trichiura infection was restricted to the Kyela site, close to Lake Nyasa with only very few cases in the other eight sites. The prevalence of T. trichiura infection in Kyela was 26.6% (95% confidence interval (CI) 23.9 to 29.6%). Multivariable models revealed a positive association of infection with denser vegetation (prevalence ratio (PR) per 0.1 EVI units = 2.12, CI 1.28 to 3.50) and inverse associations with rainfall (PR per 100 mm = 0.54, CI 0.44 to 0.67) and elevation (PR per meter = 0.89, CI 0.86 to 0.93) while adjusting for age and previous worm treatment. Slope of the terrain was modelled non-linearly and also showed a positive association with T. trichiura infection (p-value p<0.001). CONCLUSION/SIGNIFICANCE: Higher prevalences of T. trichiura infection were only found in Kyela, a study site characterized by denser vegetation, high rainfall, low elevation and flat terrain. But even within this site, we found significant influences of vegetation density, rainfall, elevation and slope on T. trichiura infection. The inverse association of rainfall with infection in Kyela is likely due to the fact, that rainfall in this site is beyond the optimum conditions for egg development. Our findings demonstrate that use of remotely sensed environmental data can aid to predict high-risk areas for targeted helminth control.


Assuntos
Tricuríase/epidemiologia , Trichuris/patogenicidade , Adolescente , Animais , Estudos Transversais , Feminino , Humanos , Masculino , Fatores de Risco , Tanzânia/epidemiologia
16.
BMC Infect Dis ; 16(1): 613, 2016 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-27793110

RESUMO

BACKGROUND: Information about improvements in the health status of population at-risk of helminth infection after anthelminthic treatment helps to evaluate the effectiveness of the large scale deworming program. The objectives of this study were to assess the impact of anthelminthic treatment on the prevalence and intensity of intestinal helminth infection, haemoglobin level and prevalence of anaemia among school-age children. METHODS: A total of 403 children attending Tikur Wuha Elementary School in Jiga, northwestern Ethiopia were enrolled in this study between February and March 2011. Formol-ether concentration and Kato-Katz methods were used to examine stool for intestinal helminth infections at baseline and one month after anthelminthic treatment. Haemoglobin level was measured using Hemocue machine at baseline and one month after anthelminthic treatment. RESULTS: Out of 403 school children examined, 15.4 % were anaemic and 58.3 % were infected with intestinal helminths at baseline. Hookworms (46.9 %), Schistosoma mansoni (24.6 %), Ascaris lumbricoides (4.2 %) and Trichuris trichiura (1.7 %) infections were common. The odds of anaemia was higher among children infected with helminths (adjusted odds ratio (aOR) = 3.83, 95 % CI = 1.92, 7.62) especially in those infected with hookworm (aOR = 2.42, 95 % CI = 1.34, 4.39) or S. mansoni (aOR = 2.67, 95 % CI = 1.46, 4.88) and two or more helminth species (aOR = 7.31, 95 % CI = 3.27, 16.35) than those uninfected with intestinal helminths at baseline. Significant reduction in prevalence of helminth infection (77.0 %) and increment in mean haemoglobin level (+3.65 g/l) of children infected with helminths was observed one month after anthelminthic treatment. The increase in haemoglobin level after anthelminthic treatment was significantly positively associated with the age, but negatively associated with the haemoglobin level at baseline. The change in mean haemoglobin level was significantly higher among undernourished than normal children. Percent reduction in the prevalence of anaemia among children infected with helminths was 25.4 % after anthelminthic treatment. CONCLUSIONS: The present study provides evidence that anthelminthic treatment of school-age children infected with intestinal helminth can improve haemoglobin level in addition to reducing the prevalence and intensity of helminth infections one month after treatment. This suggests that deworming of children may benefit the health of children in sub-Sharan Africa where hookworm and S. mansoni infections are prevalent.


Assuntos
Anemia/tratamento farmacológico , Anti-Helmínticos/uso terapêutico , Helmintíase/tratamento farmacológico , Helmintíase/epidemiologia , Enteropatias Parasitárias/tratamento farmacológico , Enteropatias Parasitárias/epidemiologia , Adolescente , Ancylostomatoidea/patogenicidade , Anemia/epidemiologia , Anemia/etiologia , Animais , Ascaris lumbricoides/patogenicidade , Criança , Pré-Escolar , Etiópia/epidemiologia , Fezes/parasitologia , Feminino , Helmintíase/complicações , Infecções por Uncinaria/complicações , Infecções por Uncinaria/tratamento farmacológico , Infecções por Uncinaria/epidemiologia , Humanos , Enteropatias Parasitárias/complicações , Masculino , Schistosoma mansoni/patogenicidade , Instituições Acadêmicas , Trichuris/patogenicidade
17.
PLoS One ; 11(5): e0155915, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27203749

RESUMO

BACKGROUND: Soil-transmitted helminths (STH) and Schistosoma mansoni infections are the major neglected tropical diseases that result in serious consequences on health, education and nutrition in children in developing countries. The Ethiopian Orthodox church students, who are called Yekolotemari in Amharic, live in areas with poor sanitation and hygiene. Moreover, they are not included in the national STH control programs. Thus, STH and S. mansoni infections prevalence is unknown. METHODS: A cross-sectional study was conducted on 384 students in June 2014 to determine STH and S. mansoni infections prevalence. Moreover, the knowledge of students about STH and S. mansoni was assessed. Data on knowledge and clinical symptoms were collected using structured questionnaires via face to face interview. Stool specimens were examined by formol-ether concentration method. RESULTS: The overall prevalence of intestinal helminths infections was 85.9% (95% confidence interval (CI): 82.1-89%). STHs infections prevalence was 65.6% (95% CI: 60.7-70.2%). The prevalence of hookworm, Ascaris lumbricoides and Trichuris trichiura were 31.8% (95% CI: 27.3-36.6%), 29.4% (25-31%) and 3.1% (1.8-5.4%), respectively. On the other hand, S. mansoni prevalence was 14.3% (95% CI: 11.1-18.1%). Majority of students infected with S. mansoni had bloody stool with crud odds-ratio of 2.9 (95% CI: 1.5-5.5). Knowledge assessment showed that 50 (13%) and 18 (4.9%) of the respondents knew about transmission of STH and S. mansoni, respectively. CONCLUSIONS: The prevalence of STH and S. mansoni infections were high thus de-worming program should include the students of Ethiopian Orthodox churches. Furthermore, provision and use of sanitary facilities, health education for students to create awareness of parasitic infections and improved personal hygiene should be in place.


Assuntos
Esquistossomose mansoni/epidemiologia , Solo/parasitologia , Adolescente , Ancylostomatoidea/patogenicidade , Animais , Ascaríase/epidemiologia , Ascaríase/parasitologia , Ascaris lumbricoides/patogenicidade , Criança , Estudos Transversais , Etiópia/epidemiologia , Feminino , Helmintíase/epidemiologia , Helmintíase/parasitologia , Helmintos/patogenicidade , Infecções por Uncinaria/epidemiologia , Infecções por Uncinaria/parasitologia , Humanos , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Intestinos/parasitologia , Masculino , Esquistossomose mansoni/parasitologia , Estudantes/estatística & dados numéricos , Trichuris/patogenicidade
18.
Infect Immun ; 84(2): 491-501, 2016 02.
Artigo em Inglês | MEDLINE | ID: mdl-26644379

RESUMO

Immunological cross talk between mucosal tissues such as the intestine and the lung is poorly defined during homeostasis and disease. Here, we show that a low-dose infection with the intestinally restricted helminth parasite Trichuris muris results in the production of Th1 cell-dependent gamma interferon (IFN-γ) and myeloid cell-derived interleukin-10 (IL-10) in the lung without causing overt airway pathology. This cross-mucosal immune response in the lung inhibits the development of papain-induced allergic airway inflammation, an innate cell-mediated type 2 airway inflammatory disease. Thus, we identify convergent and nonredundant roles of adaptive and innate immunity in mediating cross-mucosal suppression of type 2 airway inflammation during low-dose helminth-induced intestinal inflammation. These results provide further insight in identifying novel intersecting immune pathways elicited by gut-to-lung mucosal cross talk.


Assuntos
Enteropatias Parasitárias/imunologia , Intestinos/imunologia , Intestinos/parasitologia , Pulmão/imunologia , Hipersensibilidade Respiratória/imunologia , Tricuríase/imunologia , Trichuris/imunologia , Imunidade Adaptativa , Animais , Antígenos de Dermatophagoides/imunologia , Asma/imunologia , Asma/prevenção & controle , Linfócitos T CD4-Positivos/imunologia , Comunicação Celular , Relação Dose-Resposta Imunológica , Interações Hospedeiro-Parasita , Imunidade Inata , Imunidade nas Mucosas , Inflamação/imunologia , Interferon gama/biossíntese , Interferon gama/imunologia , Interleucina-10/biossíntese , Interleucina-10/imunologia , Enteropatias Parasitárias/parasitologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Papaína , Tricuríase/parasitologia , Trichuris/patogenicidade
19.
Biomed Res Int ; 2015: 967238, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26078975

RESUMO

The prevalence of intestinal parasites in cats from China was largely unknown prior to this study. The aim of the present study was to investigate the presence of intestinal parasites in cats from central China and also identify risk factors for parasitism. Fecal samples from 360 cats were examined using sugar flotation procedure and fecal smear test by microscope. Cats had mixed two or three kinds of parasites infections. Of the 360 cats feces, intestinal parasites positive feces were 149 (41.39%). 64 (17.78%) were infected with Toxocara cati, 61 (16.94%) with Isospora felis, 41 (11.39%) with Isospora rivolta, 33 (9.17%) with Paragonimus, 23 (6.39%) with hookworms, 11 (3.06%) with Toxoplasma-like oocysts, 10 (2.78%) with Trichuris, 4 (1.11%) with lungworm, 2 (0.56%) with Sarcocystis, and 1 (0.28%) with Trematode. The cats' living outdoor was identified as risk factor by statistical analysis. These results provide relevant basic data for assessing the infection of intestinal parasites in cats from central region of China. In conclusion, there was high prevalence of intestinal parasites in cats from China.


Assuntos
Doenças do Gato/parasitologia , Fezes/parasitologia , Enteropatias Parasitárias/parasitologia , Parasitos/isolamento & purificação , Ancylostomatoidea/isolamento & purificação , Ancylostomatoidea/patogenicidade , Animais , Gatos , China , Enteropatias Parasitárias/veterinária , Isospora/isolamento & purificação , Isospora/patogenicidade , Paragonimus/isolamento & purificação , Paragonimus/patogenicidade , Parasitos/classificação , Parasitos/patogenicidade , Fatores de Risco , Sarcocystis/isolamento & purificação , Sarcocystis/patogenicidade , Toxocara/isolamento & purificação , Toxocara/patogenicidade , Toxoplasma/isolamento & purificação , Toxoplasma/patogenicidade , Trichuris/isolamento & purificação , Trichuris/patogenicidade
20.
Trials ; 16: 187, 2015 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-25902705

RESUMO

BACKGROUND: The Hygiene Hypothesis proposes that infection exposure protects against inflammatory conditions. Helminths possess allergen-like molecules and may specifically modulate allergy-related immunological pathways to inhibit responses which protect against them. Mass drug administration is recommended for helminth-endemic communities to control helminth-induced pathology, but may also result in increased rates of inflammation-mediated diseases in resource-poor settings. Immunological studies integrated with implementation of helminth control measures may elucidate how helminth elimination contributes to ongoing epidemics of inflammatory diseases. We present the design of the Lake Victoria Island Intervention Study on Worms and Allergy-related diseases (LaVIISWA), a cluster-randomised trial evaluating the risks and benefits of intensive versus standard anthelminthic treatment for allergy-related diseases and other health outcomes. METHODS/DESIGN: The setting is comprised of island fishing communities in Mukono district, Uganda. Twenty-six communities have been randomised in a 1:1 ratio to receive standard or intensive anthelminthic intervention for a three-year period. Baseline characteristics were collected immediately prior to intervention rollout, commenced in February 2013. Primary outcomes are reported wheeze in the past 12 months and atopy (skin prick test response and allergen-specific immunoglobulin (asIg) E concentration). Secondary outcomes are visible flexural dermatitis, helminth infections, haemoglobin, growth parameters, hepatosplenomegaly, and responses to vaccine antigens. The trial provides a platform for in-depth analysis of clinical and immunological consequences of the contrasting interventions. DISCUSSION: The baseline survey has been completed successfully in a challenging environment. Baseline characteristics were balanced between trial arms. Prevalence of Schistosoma mansoni, hookworm, Strongyloides stercoralis and Trichuris trichiura was 52%, 23%, 13%, and 12%, respectively; 31% of Schistosoma mansoni infections were heavy (>400 eggs/gram). The prevalence of reported wheeze and positive skin prick test to any allergen was 5% and 20%, respectively. Respectively, 77% and 87% of participants had Dermatophagoides- and German cockroach-specific IgE above 0.35 kUA/L. These characteristics suggest that the LaVIISWA study will provide an excellent framework for investigating beneficial and detrimental effects of worms and their treatment, and the mechanisms of such effects. TRIAL REGISTRATION: This trial was registered with Current Controlled Trials (identifier: ISRCTN47196031) on 7 September 2012.


Assuntos
Albendazol/administração & dosagem , Anti-Helmínticos/administração & dosagem , Dermatite Atópica/tratamento farmacológico , Praziquantel/administração & dosagem , Hipersensibilidade Respiratória/tratamento farmacológico , Esquistossomose mansoni/tratamento farmacológico , Estrongiloidíase/tratamento farmacológico , Tricuríase/tratamento farmacológico , Albendazol/efeitos adversos , Animais , Anti-Helmínticos/efeitos adversos , Biomarcadores/sangue , Protocolos Clínicos , Dermatite Atópica/diagnóstico , Dermatite Atópica/imunologia , Dermatite Atópica/parasitologia , Esquema de Medicação , Hemoglobinas/metabolismo , Interações Hospedeiro-Parasita , Humanos , Imunoglobulina E/sangue , Testes Intradérmicos , Praziquantel/efeitos adversos , Projetos de Pesquisa , Hipersensibilidade Respiratória/diagnóstico , Hipersensibilidade Respiratória/imunologia , Hipersensibilidade Respiratória/parasitologia , Sons Respiratórios/efeitos dos fármacos , Sons Respiratórios/imunologia , Schistosoma mansoni/efeitos dos fármacos , Schistosoma mansoni/imunologia , Schistosoma mansoni/patogenicidade , Esquistossomose mansoni/diagnóstico , Esquistossomose mansoni/imunologia , Esquistossomose mansoni/parasitologia , Strongyloides stercoralis/efeitos dos fármacos , Strongyloides stercoralis/imunologia , Strongyloides stercoralis/patogenicidade , Estrongiloidíase/diagnóstico , Estrongiloidíase/imunologia , Estrongiloidíase/parasitologia , Fatores de Tempo , Resultado do Tratamento , Tricuríase/diagnóstico , Tricuríase/imunologia , Tricuríase/parasitologia , Trichuris/efeitos dos fármacos , Trichuris/imunologia , Trichuris/patogenicidade , Uganda
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