Understanding Heterogeneity in the Impact of National Neglected Tropical Disease Control Programmes: Evidence from School-Based Deworming in Kenya.

BACKGROUND: The implementation of soil-transmitted helminth (STH) treatment programmes occurs in varied environmental, social and economic contexts. Programme impact will be influenced by factors that affect the reduction in the prevalence and intensity of infections following treatment, as well as the subsequent rate of reinfection. To better understand the heterogeneity of programme impact and its underlying reasons, we investigated the influence of contextual factors on reduction in STH infection as part of the national school based deworming (SBD) programme in Kenya. MATERIALS AND METHODS: Data on the prevalence and intensity of infection were collected within the monitoring and evaluation component of the SBD programme at baseline and after delivery of two annual treatment rounds in 153 schools in western Kenya. Using a framework that considers STH epidemiology and transmission dynamics, capacity to deliver treatment, operational feasibility and financial capacity, data were assembled at both school and district (county) levels. Geographic heterogeneity of programme impact was assessed by descriptive and spatial analyses. Factors associated with absolute reductions of Ascaris lumbricoides and hookworm infection prevalence and intensity were identified using mixed effects linear regression modelling adjusting for baseline infection levels. PRINCIPAL FINDINGS: The reduction in prevalence and intensity of A. lumbricoides and hookworms varied significantly by county and within counties by school. Multivariable analysis of factors associated with programme impact showed that absolute A. lumbricoides reductions varied by environmental conditions and access to improved sanitation at schools or within the community. Larger reduction in prevalence and intensity of hookworms were found in schools located within areas with higher community level access to improved sanitation and within counties with higher economic and health service delivery indicator scores. CONCLUSIONS: The study identifies factors associated with the impact of school-based deworming and in particular highlights how access to water, sanitation and hygiene and environmental conditions influence the impact of deworming programmes.

The absence of resistance in congenitally athymic nude mice toward infection with the intestinal nematode, Trichuris muris: resistance restored by lymphoid cell transfer.

Congenitally athymic (nude) mice maintained infections of Trichuris muris for at least 40 days post-infection, whereas phenotypically normal mice expelled the worms by 18 days post-infection. Complete worm expulsion occurred in nude mice which had been given spleen cells. On the other hand, a partial resistance to the infection was observed in nude mice which received thymus or mesenteric lymph node cells. No significant worm reduction was seen by injection of immune serum.

An unusual endoscopic finding: Trichuris trichiura. Case report and review of the literature.

Detection of Trichuris trichiura during colonoscopic examination is an unusual finding, at least in developed countries. We report a case of a coincidental endoscopic diagnosis of whipworm infestation performed in a patient referred to our open-access endoscopy even before a faecal examination for ova and/or parasites had been performed. Review of literature on colonoscopic diagnosis of T. trichuria is provided.

Pediatrics: ridding children of common worm infections.

The most common worm infection in children in the United States is pinworm infection. In second place is roundworm infection. Agents that are effective against these nematodes in a high proportion of cases are available. In hookworm disease, generally seen in older children, tetrachloroethylene treatment is being supplanted by use of drugs less likely to have adverse side effect. Visceral larva migrans is difficult to diagnose and to treat, and our best hope for control lies in prevention.

[The effect of leukinferon on the invasive process in experimental helminthiases]. / Vliianie leikinferona na invazionnyi protsess pri éksperimental'nykh gel'mintozakh.

Two models of helminthiases (nippostrongyliasis and trichocephaliasis) were used to reveal the therapeutical activity of leukinferon (LF). In experimental nippostrongyliasis, the efficacy of LF was similar to that in infected young rats and mice whose sensitivity and resistance to infections were different. In the model of trichocephaliasis, the therapeutical effect of leukinferon was noticeably higher in C57BL/6 mice resistant to T. muris than in sensitive mice strains. In intact animals, LF brought about similar lymphocytic prestimulation depending on their sensitivity to infection. The infection itself also caused increased LF levels comparable to those observed during LF administration to intact animals. LF-induced differences in cell prestimulation were especially great as infection progressed in animals whose sensitivity to host helminths was opposite. The levels of splenocytic LF was higher in resistant hosts (non-inbred mice with nippostrongyliasis and C57BL/6 mice with trichocephaliasis) that under the similar experimental conditions in animals (rats with nippostrongyliasis and DBA/2j mice with trichocephaliasis sensitive to host helminths).

The impact of parasite infections on the course of multiple sclerosis.

Previously, we demonstrated that helminth-infected MS patients showed significantly lower number of relapses, reduced disability scores, and lower MRI activity compared to uninfected MS subjects. In the current study, 12 patients with diagnosis of relapsing remitting MS presenting parasite infections were prospectively followed during 90 months; due to exacerbation of helminth-infection symptoms after 63 months of follow-up, 4 patients received anti-parasite treatment. Helminth-infection control was associated with significant increase in clinical and radiological MS activities. Moreover, these patients showed significant increase in the number of IFN-γ and IL-12 producing cells, and a fall in the number of TGF-ß and IL-10 secreting cells, as well as CD4+CD25+FoxP3+ Treg cells evident 3 months after anti-helminth treatment began. These new observations on parasite infections associated to MS indicate that parasite regulation of host immunity can alter the course of MS.

Geophagy as a therapeutic mediator of endoparasitism in a free-ranging group of rhesus macaques (Macaca mulatta).

Parasite levels were determined for 141 members of a naturally formed social group of rhesus macaques living under free-ranging conditions. Results indicate that group members harbor Trichuris trichiura, Balantidium coli, and large numbers of Strongyloides fuelleborni. Parasite counts decrease significantly with age in this population. Females have significantly fewer parasites than males and a significantly lower prevalence of multiple infections. There were no rank effects regarding parasitosis. While 89% of the animals examined are infected with one or more species of enteric parasite, the prevalence of diarrhea is negligible (2%). The low prevalence of diarrhea in the presence of high parasite loads may be due to the practice of geophagy, which is engaged in by 76% of group members. Soil eaten by these monkeys contains large amounts of kaolinitic clays. Kaolin-based pharmaceuticals (i.e. Kaopectate) are commonly used in human populations to treat diarrhea and intestinal upsets. The mechanical and pharmaceutical properties of the natural kaolinite-based clays may counteract the effects of parasitosis in this free-ranging population.

Tricuríase / Trichuriasis

A tricuríase é uma doença parasitária causada pelo Trichuris trichiura, com importante impacto universal. No presente artigo é apresentada uma revisão sobre os aspectos mais relevantes da tricuríase.

Parasitose intestinal: profilaxia e tratamento dessa esquecida realidade brasileira / Intestinal parasite: prophylaxis and treatment of that forgotten brazilian reality

Com o evoluir da Medicina, inúmeras técnicas, métodos de diagnóstico e tratamento foram surgindo para as novas doenças constantemente descobertas. E, nessa realidade, com freqüência deparamo-nos com médicos capazes de tratar doenças complexas, com tecnologias modernas. Porém muitos se esquecem de considerar doenças básicas da comunidade, como é o caso das parasitoses intestinais, uma realidade brasileira que, embora prevalecente nas camadas socioeconomicamente menos favorecidas, afeta todos os níveis sociais. A finalidade deste artigo é promover uma revisão bibliográfica sobre o tema e abordar as principais parasitoses, dando subsídio ao diagnóstico, e, principalmente, frisar a conscientização da necessidade das medidas preventivas

Intoxicación por sulfato de cobre administrado por vía rectal / Copper sulphate intoxication due to rectal administration

El presente trbajo expone el caso de una intoxicación por sulfato de cobre (CuSO4) en un niño que recibió el tóxico en una enema evacuante cuyo objeto era desparasitarlo. El cuadro se inició con edema palpebral que pronto progresó a facial y generalizado, palidez, hematuria y oliguria. Ya hospitalizado se comprobó: hipertensión arterial, hemoglobina 2.3g/dL, urea 300mg/dL, creatinina 5 mg/dL, aspartato aminotransferasa 92 U/L, alanina aminotransferasa 50 U/L, análisis urinario con pH de 6, proteínas, glucosa y hemoglobina positivas. En el Departamento de Pediatría del Centro Médico Nacional "Adolfo Ruiz Cortines" se le diagnosticó probable nefritis tubulointersticial tóxica. posteriormente se añadieron los diagnósticos de hepatopatía tóxica y anemia hemolítica. El niño mejoró y se dio de alta dos semanas después de su ingreso

Parasitoses intestinais / Intestinal parasitosis

A autora descreve as condutas terapêuticas nas helmintíases e protozooses intestinais analisando as indicaçSes do tratamento, os medicamentos de valor, seus paraefeitos e contra-indicaçöes. A escolha das drogas e a citaçäo de mais de um composto na terapêutica de cada infecçäo em particular, embora concedendo alguma preferência, decorreram da observaçäo de certas propriedades, em especial os aspectos ligados à tolerância, facilidade de administraçäo e disponibilidade. Menciona alguns cuidados e métodos específicos que devem ser observados na realizaçäo do exame parasitológico de fezes para um correto diagnóstico e controle de cura. Näo há dúvidas que o tratamento diminue a prevalência, reduz rapidamente a carga parasitária e consequentemente a morbidade, dificultando portanto a transmissäo, mas deve vir ao lado das medidas de assistência sanitária no controle das parasitoses intestinais