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1.
PLoS Negl Trop Dis ; 15(10): e0009893, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34705819

RESUMO

BACKGROUND: Over 240 million people are infected with schistosomiasis, the majority in sub-Saharan Africa. In Uganda, high infection rates exist in communities on the shores of Lake Victoria. Praziquantel mass drug administration (MDA) delivered by village health teams is the mainstay of schistosomiasis control. However, treatment uptake remains suboptimal, with many people unaware of treatment or thinking it is only for children. Furthermore, people are often rapidly reinfected post-treatment due to continued exposure. In three Schistosoma mansoni high endemicity lake-shore communities in Mayuge district, Eastern Uganda, we investigated the sources of schistosomiasis information, remembered content of information, and the perception of information and related practices towards the control of schistosomiasis. METHODS AND PRINCIPAL FINDINGS: Data were collected from September 2017 to March 2018 using a rapid ethnographic assessment that included transect walks, observations, individual in-depth interviews and focus group discussions. Data were analysed thematically using iterative categorisation. We found that the main sources of schistosomiasis information included health workers at government facilities, village health teams, teachers, and radio programmes produced by the Ministry of Health. These messages described the symptoms of schistosomiasis, but did not mention the side effects of praziquantel treatment. Despite this messaging, the main cause of the disease and transmission was unclear to most participants. The translation of schistosomiasis on the radio into the local language 'ekidada'-meaning swollen stomach-increased, rather than reduced, confusion about the cause(s) of schistosomiasis, due to believed links between ekidada and witchcraft, and prompted a reluctance to engage with treatment or preventative efforts. CONCLUSION AND SIGNIFICANCE: This study highlights gaps in schistosomiasis messaging. We recommend MDA is complemented by effective, evidence-based messaging on schistosomiasis transmission, prevention, and treatment, that is sensitive to local language and context issues, resulting in clear, concise, and consistent messages, to increase effectiveness.


Assuntos
Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/psicologia , Adolescente , Adulto , Animais , Anti-Helmínticos/administração & dosagem , Antropologia Cultural , Criança , Pré-Escolar , Feminino , Grupos Focais/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Lagos/parasitologia , Masculino , Administração Massiva de Medicamentos , Pessoa de Meia-Idade , População Rural/estatística & dados numéricos , Schistosoma mansoni/genética , Schistosoma mansoni/isolamento & purificação , Schistosoma mansoni/fisiologia , Esquistossomose , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/parasitologia , Uganda/epidemiologia , Adulto Jovem
2.
Trans R Soc Trop Med Hyg ; 112(5): 238-244, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29945168

RESUMO

Background: Measures of health-related quality of life (HRQoL) have been used to express the impact of neglected diseases and to generate indicators for health economic assessments. Schistosomiasis mansoni is a neglected disease with various clinical manifestations, including severe repercussions, caused by parasitic worms. Here we describe the quality of life of chronic schistosomiasis mansoni patients and estimate the quality-adjusted life years (QALYs) associated with chronic schistosomiasis mansoni in Brazil in 2015. Methods: A HRQoL study was carried out using the three-level European Quality of Life 5-Dimensions (EQ-5D-3L) questionnaire in 147 chronic schistosomiasis mansoni patients at an outpatient monitoring facility of an endemic state for schistosomiasis. Results: Losses in HRQoL were observed in all five dimensions of the EQ-5D-3L. Patients >60 y and 40-49 y of age reported the highest frequencies of problems. The average utility index was 0.71, and the median index was significantly lower among female patients and patients with comorbidities (0.68; p<0.05) compared with the entire sample. Approximately 26.7 QALYs were estimated for the study population and 31.2 QALYs for the chronic schistosomiasis mansoni patients in Brazil. Conclusions: The advanced forms of schistosomiasis mansoni, even during treatment, contribute to important health losses in the population dealing with the disease.


Assuntos
Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Esquistossomose mansoni/epidemiologia , Adulto , Idoso , Brasil/epidemiologia , Comorbidade , Efeitos Psicossociais da Doença , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Esquistossomose mansoni/economia , Esquistossomose mansoni/fisiopatologia , Esquistossomose mansoni/psicologia , Inquéritos e Questionários , Adulto Jovem
3.
BMC Public Health ; 17(1): 731, 2017 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-28934944

RESUMO

BACKGROUND: Globally school-age children, adolescents and young adults bear the highest burden of schistosomiasis. When developing a specific intervention to improve community's knowledge, attitudes, and practices (KAPs), existing KAPs must be taken into account. Therefore, this study was designed to determine schoolchildren's KAPs on schistosomiasis in the study area. METHODS: A cross-sectional study was conducted in Busanga and Kibuyi villages involving 513 schoolchildren. A pre-tested questionnaire was used to collect socio-demographic data and to assess KAP on schistosomiasis among primary schoolchildren in the study area. RESULTS: Of the 488 interviewed children, 391 (80.12%) reported to have heard of schistosomiasis, with the majority 289 (73.91%) citing school as the source of this knowledge. Swimming in the lake, worms, witchcraft, and mosquitoes were mentioned to be the cause for intestinal schistosomiasis. Fishing in the lake, drinking unboiled lake water, walking bare footed, and shaking hands were reported to be practices that may lead to contracting schistosomiasis. Only 156 (39.90%) of the study respondents reported to know the signs of intestinal schistosomiasis. Avoiding swimming in the lake, drinking unboiled water and eating unwashed fruits were mentioned as preventive measures. Nearly 85% (412) reported understanding that there was a disease known as schistosomiasis; additionally, 419 (85.86%) considered schistosomiasis as a dangerous disease and 418 (85.66%) believed that schistosomiasis was treatable. Fishermen and schoolchildren were reported to be groups most at risk of schistosomiasis infection. Visiting the lake (for swimming and other gatherings) was a common practice among study participants 471 (96.52%).Nearly 93% (451) of participants mentioned using lake water for domestic chores, and, although 407 (84.61%) reported to own a toilet at home, only 229 (55.31%) reported to always use a toilet for sanitation purposes. CONCLUSION AND RECOMMENDATION: Despite a high rate of awareness among schoolchildren regarding schistosomiasis, there was a persistent gap amongst the children regarding the causes, modes of transmission, symptoms, and preventive measures for the disease. Therefore, an appropriate health education intervention is needed in order to inculcate better knowledge, attitudes, and practices amongst schoolchildren regarding its transmission, control, and prevention as part of a successful schistosomiasis campaign.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Esquistossomose mansoni/psicologia , Adolescente , Criança , Estudos Transversais , Feminino , Humanos , Lagos , Masculino , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/prevenção & controle , Instituições Acadêmicas , Inquéritos e Questionários , Tanzânia/epidemiologia
4.
BMC Infect Dis ; 13: 590, 2013 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24330594

RESUMO

BACKGROUND: Realization of the public health benefits of mass drug administration (MDA) for the control of schistosomiasis depends on achieving and maintaining high annual treatment coverage. In Uganda, the uptake of preventive treatment for schistosomiasis among school-age children in 2011 was only 28%. Strategies are needed to increase uptake. METHODS: Serial cross-sectional surveys were conducted at baseline (after MDA in 2011) and at follow-up MDA in 2012 where teacher motivation was provided and supervision strengthened in Jinja district of Uganda. Uptake of praziquantel was assessed in 1,010 randomly selected children from 12 primary schools during the baseline survey and in another set of 1,020 randomly selected children from the same primary schools during the follow-up survey. RESULTS: Self-reported uptake of praziquantel increased from 28.2% (95% CI 25.4%-30.9%) at baseline to 48.9% (95% CI 45.8%-52.0%) (p < 0.001) at follow-up. Prevalence and intensity of Schistosoma mansoni infection were unchanged and moderate on both occasions; 35.0% (95% CI: 25.4%-37.9%) and 32.6% (95% CI: 29.6%-35.5%) (p = 0.25) and 156.7 eggs per gram of stool (epg) (95% CI: 116.9-196.5) and 133.1 epg (95% CI: 99.0-167.2) (p = 0.38), respectively. There was no change in the proportion of children reporting side effects attributable to praziquantel at baseline (49.8%, 95% CI 43.8%-55.8%) and at follow-up (46.6%, 95% CI 42%.1-51.2%) (p = 0.50) as well as in the proportion of children with correct knowledge of schistosomiasis transmission and control between the baseline (45.9%, 95% CI 42.7%-73.7%) and follow-up (44.1%, 95% CI 41.0%- 47.2%) (p = 0.42). CONCLUSION: Although teacher motivation and supervision to distribute treatment increased the uptake of praziquantel among school-age children, the realized uptake is still lower than is recommended by the World Health Organization (WHO) and apparently too low to affect the prevalence and intensity of schistosomiasis among the children. Additional measures are needed to increase uptake of praziquantel if school-based MDA is to achieve the objective of preventive chemotherapy.


Assuntos
Anti-Helmínticos/administração & dosagem , Praziquantel/administração & dosagem , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/psicologia , Adolescente , Animais , Criança , Estudos Transversais , Docentes , Feminino , Seguimentos , Humanos , Masculino , Adesão à Medicação , Motivação , Prevalência , Schistosoma mansoni/efeitos dos fármacos , Schistosoma mansoni/isolamento & purificação , Schistosoma mansoni/fisiologia , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/prevenção & controle , Instituições Acadêmicas , Estudantes/psicologia , Uganda/epidemiologia
5.
East Afr Med J ; 84(2): 56-66, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17598666

RESUMO

OBJECTIVE: To elicit and understand peoples' perceptions of intestinal schistosomiasis that is a prerequisite for designing appropriate control strategies. DESIGN: Cross-sectional study using six focus group discussions (FGDs) and 432 semi-structured interviews (SSIs). SUBJECTS: Community members in Busia district of Uganda. MAIN OUTCOME MEASURES: Data was collected on causes, transmission, health seeking behaviour, hygiene behaviour and on prevention/control strategies for schistosomiasis. RESULTS: The symptoms of early intestinal schistosomiasis were poorly understood whereas those of late schistosomiasis were well appreciated. Cause and transmission of schistosomiasis were used interchangeably and schistosomiasis was mainly thought to be caused by drinking dirty or unboiled water. Schistosomiasis was perceived to be a treatable disease and modern medicines were said to be effective. Community members said that it is impossible to avoid contact with possible sources of infection for schistosomiasis as the lake was linked to livelihood of people. The groups that were particularly at increased risk of not participating in schistosomiasis prevention strategies included women, the uneducated and those involved in subsistence agriculture. CONCLUSIONS: In order to effectively control schistosomiasis in this district, there is need to adapt prevention and control strategies to peoples' livelihoods. There is also need to target the less advantaged groups (women, uneducated and subsistence farmers) for intense health education strategies aimed at increasing participation in the control of schistosomiasis.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Características de Residência , Esquistossomose mansoni/psicologia , Adulto , Animais , Estudos Transversais , Coleta de Dados , Feminino , Grupos Focais , Comportamentos Relacionados com a Saúde , Humanos , Entrevistas como Assunto , Enteropatias Parasitárias/psicologia , Enteropatias Parasitárias/transmissão , Masculino , Fatores de Risco , Esquistossomose mansoni/transmissão , Uganda
6.
Trop Med Int Health ; 9(7): 784-94, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15228488

RESUMO

Morbidity control of schistosomiasis through integration within existing health care delivery systems is considered a potentially sustainable and cost-effective approach. We conducted a questionnaire-based field study in a Ghanaian village endemic for both urinary and intestinal schistosomiasis to determine whether infected individuals self-reported to health centres or clinics and to identify factors that influenced their decision to seek health care. A total of 317 subjects were interviewed about having signs and symptoms suggestive of schistosomiasis: blood in urine, painful urination, blood in stool/bloody diarrhoea, abdominal pain, diarrhoea, swollen abdomen and fatigue within 1 month of the day of the interview. Fever (for malaria) was included as a disease of high debility for comparison. Around 70% with blood in urine or painful urination did not seek health care, whilst diarrhoea, blood in stool, abdominal pain and fever usually led to action (mainly self-medication, with allopathic drugs being used four to five times more often than herbal treatment). On average 20% of schistosomiasis-related signs and symptoms were reported to health facilities either as the first option or second and third alternative by some of those that self-medicated. A few of those who visited a clinic or health centre as first option still self-medicated afterwards. Children under 10 years and adults were more likely to seek health care than teenagers. Also, females were more likely to visit a health facility than males of the same age groups. Socio-economic status and duration of symptoms did not appear to affect health-seeking behaviour. 'Do not have the money' (43%) and 'Not serious enough' (41%) were the commonest reasons for not visiting a clinic, reported more frequently by lower and higher socio-economic classes, respectively, for both urinary or intestinal schistosomiasis. The regular health service shows some potential in passive control of schistosomiasis as some, but far too few, people visit a health facility as first or second option.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Esquistossomose Urinária/terapia , Esquistossomose mansoni/terapia , Adolescente , Adulto , Anti-Helmínticos/uso terapêutico , Criança , Pré-Escolar , Diarreia/etiologia , Feminino , Gana , Hematúria/etiologia , Humanos , Lactente , Masculino , População Rural , Esquistossomose Urinária/psicologia , Esquistossomose mansoni/psicologia
7.
Antimicrob Agents Chemother ; 47(12): 3853-8, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14638494

RESUMO

The activity of the acyclic nucleotide analogue 9-(S)-[3-hydroxy-2-(phosphonomethoxy)propyl]adenine [(S)-HPMPA] against Schistosoma mansoni was investigated in mice. The compound was injected intraperitoneally, usually on two or five consecutive days, at 10 to 20 mg/kg of body weight/day. The treatment started before, at the time of, and after the onset of egg laying (oviposition) by S. mansoni. The animals were killed from 7 to 40 days after the cessation of treatment. Significant reductions in the total numbers of female and coupled worms were found. Female fecundity and both hepatic and intestinal egg loads were suppressed. These effects were more pronounced with dosing regimens launched before the time of oviposition. The complete disappearance of immature eggs and a significant reduction to the complete absence of mature eggs, with 99 to 100% of the eggs being dead, were produced. No hepatic egg-induced granulomas were present in mice treated at the time of oviposition, and the granulomas were smaller in mice treated before S. mansoni oviposition. These preliminary findings extend the knowledge of the antiparasitic properties of (S)-HPMPA.


Assuntos
Adenina/análogos & derivados , Adenina/uso terapêutico , Organofosfonatos , Compostos Organofosforados/uso terapêutico , Schistosoma mansoni , Esquistossomose mansoni/tratamento farmacológico , Esquistossomicidas/uso terapêutico , Animais , Feminino , Fertilidade , Granuloma/patologia , Intestinos/parasitologia , Fígado/parasitologia , Fígado/patologia , Masculino , Camundongos , Contagem de Ovos de Parasitas , Praziquantel/uso terapêutico , Esquistossomose mansoni/psicologia
8.
Trop Med Int Health ; 8(8): 744-9, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12869097

RESUMO

We evaluated the awareness of and knowledge about intestinal schistosomiasis in a highly infected rural community of northern Senegal where a variety of health information and education activities had taken place for 7 years as a component of different research and control programmes. As the infection had been introduced only recently, an initial 'zero' knowledge can be assumed. Most of the health education activities had been performed with adapted messages through local health and community workers. By a questionnaire, 566 individuals were asked simple questions on symptoms, mode of transmission, the sources of information and health-seeking behaviour. About 86% of the respondents stated that they knew what schistosomiasis was, and 92% that in case of illness they would seek treatment at the health centre. However, only half of the people accurately quoted symptoms associated with intestinal schistosomiasis: diarrhoea, abdominal pain and bloody stools. The majority of respondents realized that the disease was somehow linked with water and (lack of) hygiene, but only 44% of respondents reported water contact as the source of infection. Ultimately, only 30% of the respondents gave adequate answers about both symptoms and mode of transmission. We conclude that even intense and long-lasting education efforts for a specific and straightforward problem as schistosomiasis are not enough to have profound impact on the knowledge of rural traditional communities.


Assuntos
Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Esquistossomose mansoni/prevenção & controle , Adulto , Criança , Feminino , Humanos , Controle de Infecções/métodos , Masculino , Avaliação de Programas e Projetos de Saúde , Saúde da População Rural , Esquistossomose mansoni/psicologia , Esquistossomose mansoni/transmissão , Senegal , Inquéritos e Questionários
9.
Physiol Behav ; 75(4): 449-54, 2002 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12062309

RESUMO

Schistosomiasis is a parasitic disease of humans and rodents affecting more than 200 million people worldwide. Following the onset of infection, the worms induce granulomas around schistosome eggs in the liver, intestine and central nervous system (both brain and spinal cord), which are likely to cause changes in cognitive functions. In the present study, CD-1 female mice were percutaneously infected with 60 cercariae of Schistosoma mansoni and the effect on the mice's cognitive abilities were assessed by using the passive avoidance learning paradigm both in an early and a late phase of infection (independent groups). The results of the study show that infected animals without brain granulomas (early phase) had impairments in their passive avoidance response, whereas mice with brain granulomas (late phase) behaved as uninfected ones. Moreover, a decreased propensity to start exploration was observed in mice with granulomas in the brain. The results suggest that the murine model of infection may be a useful tool for studying human neuroschistosomiasis.


Assuntos
Aprendizagem da Esquiva/fisiologia , Esquistossomose mansoni/psicologia , Animais , Encéfalo/parasitologia , Encéfalo/patologia , Feminino , Granuloma/parasitologia , Granuloma/patologia , Hipocampo/parasitologia , Hipocampo/patologia , Memória/fisiologia , Camundongos
10.
Physiol Behav ; 65(2): 347-53, 1998 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-9855486

RESUMO

In this study, CD-1 mice were infected percutaneously with 1600 cercariae of Schistosoma mansoni and their pain sensitivity and exploratory behavior were analyzed in well-standardized tests (hot-plate, hole-board, open-field, novel object investigation and black/white box). Schistosome infection produced body weight reduction, increased analgesia, induced changes in the number of fecal pellets emitted during the hole-board and the black/white tests, induced decreased locomotion in the open-field, decreased sniffing, rearing, wall-rearing and time spent in exploratory activity. The infection also lengthened the latency time to the first transition from the white into the black compartment in the black/white box, index of enhanced anxiety. The present findings indicate that the analgesia is one of the main effects of the disease suggesting that schistosome infection induces maladaptive response in exploratory behavior and in locomotor activity of the host associated with altered motivational and attentional levels. Furthermore, though mouse behavioral changes appear to be similar to those observed in parasite/host systems where the changes are supposed to be adaptive for the parasite, in the case of Schistosoma/mouse system, the changes in host behavior resulted to be not adaptive for the parasite.


Assuntos
Comportamento Exploratório/fisiologia , Dor/psicologia , Esquistossomose mansoni/psicologia , Animais , Peso Corporal , Feminino , Camundongos , Atividade Motora/fisiologia , Medição da Dor , Tempo de Reação/fisiologia
11.
Physiol Behav ; 62(2): 399-406, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9251986

RESUMO

In this study, CD-1 female mice, deprived of the submaxillary salivary glands, were infected with S. mansoni and their behavior was observed 15 weeks after infection, when the eggs of the parasite are present in the brain. Sialectomized infected mice showed changes in exploratory activity, sniffing, and wall-rearing in the open-field and in the black/white box, but no differences in pain sensitivity were observed on the hot plate. The present results suggest that the modifications in the behavior of sialectomized infected mice might be associated with the inability of the animals to cope with the aversive effects of the infection and, most probably, with modifications in the levels of polypeptides released into the bloodstream by the salivary glands, affecting the NGF-responsive cells of the nervous, endocrine, and immune systems.


Assuntos
Comportamento Exploratório/fisiologia , Limiar da Dor/fisiologia , Schistosoma mansoni , Esquistossomose mansoni/psicologia , Glândula Submandibular/fisiologia , Animais , Peso Corporal/fisiologia , Feminino , Asseio Animal/fisiologia , Temperatura Alta , Camundongos , Fatores de Crescimento Neural/fisiologia , Ratos
12.
J Egypt Soc Parasitol ; 26(1): 285-96, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8721249

RESUMO

Effect of pairing on susceptibility of male Syrian hamsters to Schistosoma mansoni infection in comparison to their isolated counter-parts have been studied. Pairing resulted in significant differences between paired and isolated hamsters in measurements of eggs, miracidia, number of adult worms recovered and mean testicular number of males. Paired hamsters seemed to be immunologically suppressed and such a suppression resulted in increasing the fertility and number of worms recovered. The width of the male schistosomes recovered from the paired hamsters was two folds and the length was four folds greater than those recovered from isolated ones. The mean testicular number was 8.17 +/- 0.53 in males recovered from paired hamsters and 6.16 +/- 0.71 in those recovered from isolated ones. Of interest was, the demonstration of a male with two groups of testes recovered from a paired hamster. It was concluded that the stressed host reflex effects on the number and fertility of the schistosome worms burden, and hence the severity of the disease and its complications.


Assuntos
Fígado/parasitologia , Schistosoma mansoni/fisiologia , Esquistossomose mansoni/psicologia , Estresse Psicológico , Animais , Biomphalaria/parasitologia , Cricetinae , Aglomeração , Suscetibilidade a Doenças , Feminino , Fertilidade , Masculino , Mesocricetus , Contagem de Ovos de Parasitas , Schistosoma mansoni/isolamento & purificação , Esquistossomose mansoni/fisiopatologia , Isolamento Social , Testículo/parasitologia
13.
Trop Med Parasitol ; 43(3): 162-6, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1470834

RESUMO

Human- and snail-related aspects of the transmission of schistosomiasis mansoni was studied in the Amor Parish community located at the western bank of the River Nile in the Nebbi District, north-western Uganda. A cross sectional survey involving 642 people revealed an overall prevalence of infection among males and females of 81.6% and 81.3%, respectively. The prevalence of infection peaked in the 10-14 years age group, being 93.2% and 93.6% in males and females, respectively, but the prevalence remained high also in older age groups. Intensity of infection peaked in the 10-14 years age group in males and in the 15-19 years age group in females, reaching 768 and 482 eggs/g faeces, respectively. Intensity of infection diminished only to a moderate extent with increasing age with the infection intensity in the 40+ years age group being 270 and 241 eggs/g faeces in males and females, respectively. Observations on the human water contact pattern revealed a community having a very intensive water contact persisting into old age. Interviews revealed a high level of awareness of the disease schistosomiasis, and 87.2% had a history of passing blood in stool. The total set of observations point to intestinal schistosomiasis being of public health importance in Amor Parish. Studies on snail-related aspects of transmission revealed that Biomphalaria stanleyi was by far the most important snail host in the area. A tendency was seen for B. stanleyi snail numbers to be reduced during the rainy season.


Assuntos
Esquistossomose mansoni/epidemiologia , Adolescente , Adulto , Fatores Etários , Animais , Biomphalaria/parasitologia , Criança , Pré-Escolar , Estudos Transversais , Vetores de Doenças , Fezes/parasitologia , Feminino , Água Doce , Humanos , Lactente , Masculino , Contagem de Ovos de Parasitas , Prevalência , Schistosoma/isolamento & purificação , Esquistossomose mansoni/psicologia , Esquistossomose mansoni/transmissão , Estações do Ano , Fatores Sexuais , Uganda/epidemiologia
14.
Eur J Immunol ; 16(6): 589-95, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3087755

RESUMO

Most helminth parasites induce a strong IgE antibody and elevated eosinophil response in their mammalian hosts and a number of in vitro studies have suggested that IgE, possibly in association with eosinophils, may be an essential element of the host protective immunity against helminth infections. To assess the role of IgE in protective immunity, we examined the effect of suppressing the IgE antibody response on rat immunity to Schistosoma mansoni. Suppression was achieved in neonates by injections of rabbit anti-epsilon chain gamma-globulins, control rats received injections of unspecific gamma-globulins. IgE suppression caused a marked reduction of the inflammatory reaction that developed in the skin of immune rats at the site of a cercarial challenge: the early (30 to 60 min) wheal and flare reaction was abolished, and the late cutaneous reaction (6 to 18 h) associated with intense pruritus, edema and local eosinophilia was greatly reduced. This shows that IgE was critical to the recruitment of effector cells and molecules in the skin during the first 24 h following parasite invasion. Worms were recovered 18 to 30 days after a primary infection and 18 days after a challenge infection from IgE-suppressed and control rats. IgE-suppressed rats cured a first infection as rapidly as the control rats; however, they were two to three times less efficient than the controls at eliminating a second or a third challenge. These observations demonstrate that IgE antibodies are essential for the full development of rat acquired protective immunity against Schistosoma mansoni.


Assuntos
Tolerância Imunológica , Imunoglobulina E/fisiologia , Esquistossomose mansoni/imunologia , Testes Cutâneos , Animais , Anticorpos Anti-Idiotípicos/administração & dosagem , Imunidade Inata , Imunoglobulina E/biossíntese , Imunoglobulina E/imunologia , Cadeias épsilon de Imunoglobulina/imunologia , Coelhos , Ratos , Ratos Endogâmicos Lew , Schistosoma mansoni/imunologia , Esquistossomose mansoni/patologia , Esquistossomose mansoni/psicologia
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