Effectiveness of the Brazilian Visceral Leishmaniasis Surveillance and Control Programme in reducing the prevalence and incidence of Leishmania infantum infection.

Background Control strategies adopted by the Brazilian Visceral Leishmaniasis Surveillance and Control Programme (VLSCP) include identifying and culling seropositive infected dogs, early diagnosis and treatment of human cases, chemical control of the vector and population awareness. This study evaluated the effectiveness of the VLSCP on the prevalence and incidence rates of Leishmania infantum in children residing in areas under different VLSCP intervention times. Methods A quasi-experimental epidemiological study with a panel (two cross-sectional) and a concurrent cohort was performed in three areas of Belo Horizonte, southeast Brazil. The first cross-sectional study (I) was carried out with 1875 children, 478 of which were enrolled in the cohort study. In the second cross-sectional study (II), 413 additional children were included, totalizing 891 children. Laboratory diagnosis was performed by ELISA-rK39. Analyses included multilevel logistic and Poisson regression models. Results The incidence rates of L. infantum infection were: 14.4% in the area where VLSCP intervention was initiated in 2006 (AI2006); 21.1% in the area where intervention was initiated in 2008 (AI2008); and 11.6% in the area where intervention was initiated in 2010 (AI2010 - control area). A follow-up period of 24 months showed that the persons-time incidence rates in AI2006, AI2008, and AI2010 were: 6.2/100, 10/100, and 5.6/100 persons/24 months, respectively. The final prevalence rates of infection (cross-sectional II - in 2012), compared to the initial rates (cross-sectional I - in 2010), increased 83.7% in AI2006, 74.1% in AI2008, and decreased 5% in AI2010. Analysis of the effectiveness revealed that children residing in AI2008 are more likely to be infected (OR = 1.84; 95% CI: 1.06-3.23) and present a higher risk of infection (IRR = 1.76; 95% CI: 1.05-2.95) compared to those in AI2010. No statistically significant differences were observed in asymptomatic infection (OR and IRR) in AI2006 compared to AI2010. Conclusions The VLSCP was not effective at controlling L. infantum infection in areas where interventions had respectively been carried out for six and four years. However, it is unclear what the consequences in terms of human infection and diseases would be in the absence of the VLSCP. Efforts to improve the effectiveness of control measures remain a necessary priority

Efetividade do Programa de Vigilância e Controle da leishmaniose visceral sobre as taxas de incidência e prevalência da infecção assintomática por Leishmania (Leishmania) infantum, Belo Horizonte MG

Exportado OPUSMade available in DSpace on 2019-08-11T09:18:40Z (GMT). No. of bitstreams: 1 tese_final___iara_caixeta.pdf: 5468381 bytes, checksum: 09a260363a01b20140a4e87d43c38627 (MD5) Previous issue date: 9Este estudo avaliou por meio dos delineamentos epidemiológicos transversal e coorte, a efetividade das estratégias do Programa de Vigilância e Controle da Leishmaniose Visceral (PVC-LV), sobre a infecção por Leishmania infantum em crianças. O estudo foi conduzido no ano de 2012 em três áreas de Belo Horizonte, com diferentes tempos de intervenção pelo PVC-LV (Área de intervenção 2006: AI2006, Área de intervenção: AI2008 e Área de intervenção: AI2010). No delineamento transversal foram avaliadas 891 crianças. As taxas de prevalência por ELISA-rK39, nas AI2006, AI2008 e AI2010 foram respectivamente 23,7% (IC95% 19,1-28,9), 25,6% (IC95% 21,1-30,7) e 17,0 (IC95% 13,1-21,8). Observou-se, que as taxas de prevalência da infecção assintomática, quando comparadas às taxas de prevalência estimadas em 2010 por Morais. (2011), mostraram 83,7% de aumento na área com maior tempo de intervenção (AI2006), 74,1% de aumento na área com tempo intermediário de intervenção (AI2008) e diminuição de 5% na área controle, com menor tempo de intervenção (AI2010). No delineamento de coorte foram seguidas 478 crianças, que apresentaram testes sorológicos não reagentes para L. infantum em 2010, no estudo de Morais (2011). As taxas de incidência bruta foram 14,4% na AI2006, 21,1% na AI2008 e 11,6% na área controle, AI2010. As taxas de incidência pessoa-tempo nas áreas AI2006, AI2008 e AI2010 foram respectivamente 6,2; 10 e 5,6/100 pessoas em 24 meses de acompanhamento. As análises foram desenvolvidas utilizando os modelos de regressão logística multinível (Odds Ratio) para o delineamento transversal e regressão de Poisson (IRR - razão de incidência) para o delineamento de coorte. Crianças que residem na AI2008 mostraram maior odds de infecção (OR=1,84; IC95%=1,06-3,23) e maior razão de incidência da infecção (IRR=1,76; IC95%=1,05-2,95), quando comparada à área controle, AI2010. Na AI2006 não houve diferença estatística na odds de infecção (OR=1,68; IC95%=0,94- 2,98) e na razão de incidência da infecção (IRR=1,18; IC95%=0,65-2,14), quando comparada a AI2010. Os resultados mostraram que os tempos de intervenção e as estratégias do PVC-LV não foram efetivos para reduzir as taxas de infecção assintomática nas áreas estudadas. Mesmo observando redução discreta nas taxas de infecção na área controle, AI2010, a circulação e transmissão do parasito foram mantidas em níveis elevados em todas as áreas de estudo. Foi observado, que nenhuma criança desenvolveu sinais ou sintomas clínicos da doença, o que sugere que a infecção assintomática, embora seja um bom marcador da circulação do parasito, não está associada ao doecimento humano. Os fatores associados à infecção assintomática por L. infantum foram a idade da criança, a renda da família, a escolaridade do chefe da família e a presença de árvores na vizinhança. No domicílio, os fatores associados para que ocorra a infecção em pelo menos uma criança da residência, foram a classe socioeconômica da família e a presença de árvores na vizinhança.This study evaluated by cross-sectional and cohort epidemiological designs the effectiveness of the strategies of the Surveillance and Control Program of Visceral Leishmaniasis (SCP-VL) in the infection with Leishmania infantum in children. The study was conducted in 2012 in three areas of Belo Horizonte, with different intervention times by SCP-VL (Intervention area 2006: IA2006, intervention area: IA2008 and intervention area: IA2010). In the cross-sectional design 891 children were evaluated. Prevalence rates by ELISA-rK39 in the IA2006, IA2008 and IA2010 were respectively 23.7% (95% CI 19.1 to 28.9), 25.6% (95% CI 21.1 to 30.7) and 17 0 (95% CI 13.1 to 21.8). When compared with prevalence rates estimated at 2010 by Morais. (2011), the prevalence rates of asymptomatic infection increased 83.7% in the area with greater intervention time (IA2006), 74.1% in the area with intermediate intervention time (IA2008) and decreased 5% in the control area, with shorter intervention time (IA2010). In the cohort, 478 children with L. infantum negative serological tests in 2010 (Morais, 2011) were followed. The crude incidence rates were 14.4% in the IA2006, 21.1% and 11.6% IA2008 in the control area, IA2010. The person-time incidence rates were respectively 6.2; 10 and 5.6 / 100 people in 24 months of follow-up in IA2006, IA2008 and IA2010. The analyzes were developed using multilevel logistic regression (odds ratio) for the cross-sectional design and Poisson regression (IRR - incidence ratio) for the cohort design. The infection odds increased in IA2008 (OR = 1.84, 95% CI 1.06 to 3.23) and a higher infection incidence ratio (IRR = 1.76, 95% ; CI 1.05 to 2 95) was found compared to the control area, IA2010. In IA2006 there were no statistical differences between the infection odds (OR = 1.68; 95% ; CI = 0,94- 2,98) and incidence ratio of infection (IRR = 1.18, 95% ; CI 0.65 to 2 14) when compared to IA2010. The results showed that the intervention times and PVC-LV strategies were non effective in reducing asymptomatic infection rates in the studied areas. Even observing slight reduction at infection rates in the control area, IA2010, the circulation and transmission of the parasite were maintained at high levels in all the study areas. It was observed that nobody developed clinical signs or symptoms, which suggests that asymptomatic infection is a good marker for the parasite circulation but is not associated with human desease. The asymptomatic infection by L. infantum was associated with child's age, family socioeconomic status, education of household and presence of trees in the neighborhood. The infection occurrence in at least one child at home was associated with the family socioeconomic status and the presence of trees in the neighborhood

Effectiveness of the Brazilian Visceral Leishmaniasis Surveillance and Control Programme in reducing the prevalence and incidence of Leishmania infantum infection

Abstract Background Control strategies adopted by the Brazilian Visceral Leishmaniasis Surveillance and Control Programme (VLSCP) include identifying and culling seropositive infected dogs, early diagnosis and treatment of human cases, chemical control of the vector and population awareness. This study evaluated the effectiveness of the VLSCP on the prevalence and incidence rates of Leishmania infantum in children residing in areas under different VLSCP intervention times. Methods A quasi-experimental epidemiological study with a panel (two cross-sectional) and a concurrent cohort was performed in three areas of Belo Horizonte, southeast Brazil. The first cross-sectional study (I) was carried out with 1875 children, 478 of which were enrolled in the cohort study. In the second cross-sectional study (II), 413 additional children were included, totalizing 891 children. Laboratory diagnosis was performed by ELISA-rK39. Analyses included multilevel logistic and Poisson regression models. Results The incidence rates of L. infantum infection were: 14.4% in the area where VLSCP intervention was initiated in 2006 (AI2006); 21.1% in the area where intervention was initiated in 2008 (AI2008); and 11.6% in the area where intervention was initiated in 2010 (AI2010 - control area). A follow-up period of 24 months showed that the persons-time incidence rates in AI2006, AI2008, and AI2010 were: 6.2/100, 10/100, and 5.6/100 persons/24 months, respectively. The final prevalence rates of infection (cross-sectional II - in 2012), compared to the initial rates (cross-sectional I - in 2010), increased 83.7% in AI2006, 74.1% in AI2008, and decreased 5% in AI2010. Analysis of the effectiveness revealed that children residing in AI2008 are more likely to be infected (OR = 1.84; 95% CI: 1.06-3.23) and present a higher risk of infection (IRR = 1.76; 95% CI: 1.05-2.95) compared to those in AI2010. No statistically significant differences were observed in asymptomatic infection (OR and IRR) in AI2006 compared to AI2010. Conclusions The VLSCP was not effective at controlling L. infantum infection in areas where interventions had respectively been carried out for six and four years. However, it is unclear what the consequences in terms of human infection and diseases would be in the absence of the VLSCP. Efforts to improve the effectiveness of control measures remain a necessary priority

Low Parasite Load Estimated by qPCR in a Cohort of Children Living in Urban Area Endemic for Visceral Leishmaniasis in Brazil

<div><h3>Background</h3><p>An important issue associated with the control of visceral leishmaniasis is the need to identify and understand the relevance of asymptomatic infection caused by <em>Leishmania infantum</em>. The aim of this study was to follow the course of asymptomatic <em>L. infantum</em> infection in children in an area of Brazil where it is endemic. The children were assessed twice during a 12-month period.</p> <h3>Methodology</h3><p>In this population study, 1875 children, ranging from 6 months to 7 years of age, were assessed. Blood samples were collected on filter papers via finger prick and tested by ELISA (<em>L. infantum</em> soluble antigen and rk39). Seropositives samples (n = 317) and a number of seronegatives samples (n = 242) were subjected to qPCR. After 12 months, blood samples were collected from a subgroup of 199 children and tested for <em>Leishmania</em> spp. to follow the course of infection.</p> <h3>Principal Findings</h3><p>At baseline qPCR testing identified 82 positive samples. The prevalence rate, as estimated for 1875 children based on the qPCR results, was 13.9%. The qPCR testing of whole blood samples collected from a cohort of children after 12 months (n = 199) yielded the following results: of the 44 (22.1%) children with positive qPCR results at baseline, only 10 (5.0%) remained positive, and 34 (17.1%) became negative; and of the 155 (77.9%) children with negative qPCR results, 131 (65.8%) remained negative, and 24 (12.1%) became positive at the follow-up measurement. The samples with positive findings at baseline (n = 82) had a mean of 56.5 parasites/mL of blood; and at follow-up the mean positive result was 7.8 parasites/mL.</p> <h3>Conclusions</h3><p>The peripheral blood of asymptomatic children had a low and fluctuating quantity of <em>Leishmania</em> DNA and a significant decrease in parasitemia at 1-year follow-up. Quantitative PCR enables adequate monitoring of <em>Leishmania</em> infection.</p> </div

Mitochondrial cardioencephalomyopathy due to a novel SCO2 mutation in a Brazilian patient: case report and literature review

O artigo encontra-se disponível em acesso aberto no site do Editor.Submitted by Nuzia Santos ([email protected]) on 2019-07-03T18:12:25Z No. of bitstreams: 1 Mitochondrial Cardioencephalomyopathy.pdf: 479414 bytes, checksum: 597b5f7fb79cf70e2eec80ce570bde7a (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2019-07-03T18:19:17Z (GMT) No. of bitstreams: 1 Mitochondrial Cardioencephalomyopathy.pdf: 479414 bytes, checksum: 597b5f7fb79cf70e2eec80ce570bde7a (MD5)Made available in DSpace on 2019-07-03T18:19:17Z (GMT). No. of bitstreams: 1 Mitochondrial Cardioencephalomyopathy.pdf: 479414 bytes, checksum: 597b5f7fb79cf70e2eec80ce570bde7a (MD5) Previous issue date: 2013Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Parasitologia. Laboratório de Epidemiologia das Doenças Infecciosas e Parasitárias. Belo Horizonte, MG, Brasil / Prefeitura de Belo Horizonte. Secretaria Municipal de Saúde. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Parasitologia. Laboratório de Epidemiologia das Doenças Infecciosas e Parasitárias. Belo Horizonte, MG, Brasil.Universidade Federal de Ouro Preto. Escola de Farmácia. Pós-graduação em Ciências Farmacêuticas. Departamento de Análises Clínicas. Ouro Preto, MG, Brasil / Universidade Federal de Ouro Preto. Núcleo de Pesquisa em Ciências Biológicas. Pós-graduação em Ciências Biológicas. Ouro Preto, MG, Brasil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Parasitologia. Laboratório de Epidemiologia das Doenças Infecciosas e Parasitárias. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Parasitologia. Laboratório de Epidemiologia das Doenças Infecciosas e Parasitárias. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Parasitologia. Laboratório de Epidemiologia das Doenças Infecciosas e Parasitárias. Belo Horizonte, MG, Brasil / Santa Casa de Belo Horizonte. Instituto de Ensino e Pesquisa. Belo Horizonte, MG, Brasil.Prefeitura de Belo Horizonte. Secretaria Municipal de Saúde. Belo Horizonte, MG, Brasil.Fundação Oswaldo Cruz. Instituto René Rachou. Laboratório de Pesquisas Clínicas. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Instituto de Ciências Exatas. Departamento de Estatística. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Parasitologia. Laboratório de Epidemiologia das Doenças Infecciosas e Parasitárias. Belo Horizonte, MG, Brasil / Universidade Federal de Minas Gerais. Faculdade de Medicina. Pós-graduação em Ciências da Saúde: Infectologia e Medicina Tropical. Belo Horizonte, MG, Brasil.BACKGROUND: Control strategies adopted by the Brazilian Visceral Leishmaniasis Surveillance and Control Programme (VLSCP) include identifying and culling seropositive infected dogs, early diagnosis and treatment of human cases, chemical control of the vector and population awareness. This study evaluated the effectiveness of the VLSCP on the prevalence and incidence rates of Leishmania infantum in children residing in areas under different VLSCP intervention times. METHODS: A quasi-experimental epidemiological study with a panel (two cross-sectional) and a concurrent cohort was performed in three areas of Belo Horizonte, southeast Brazil. The first cross-sectional study (I) was carried out with 1875 children, 478 of which were enrolled in the cohort study. In the second cross-sectional study (II), 413 additional children were included, totalizing 891 children. Laboratory diagnosis was performed by ELISA-rK39. Analyses included multilevel logistic and Poisson regression models. RESULTS: The incidence rates of L. infantum infection were: 14.4% in the area where VLSCP intervention was initiated in 2006 (AI2006); 21.1% in the area where intervention was initiated in 2008 (AI2008); and 11.6% in the area where intervention was initiated in 2010 (AI2010 - control area). A follow-up period of 24 months showed that the persons-time incidence rates in AI2006, AI2008, and AI2010 were: 6.2/100, 10/100, and 5.6/100 persons/24 months, respectively. The final prevalence rates of infection (cross-sectional II - in 2012), compared to the initial rates (cross-sectional I - in 2010), increased 83.7% in AI2006, 74.1% in AI2008, and decreased 5% in AI2010. Analysis of the effectiveness revealed that children residing in AI2008 are more likely to be infected (OR = 1.84; 95% CI: 1.06-3.23) and present a higher risk of infection (IRR = 1.76; 95% CI: 1.05-2.95) compared to those in AI2010. No statistically significant differences were observed in asymptomatic infection (OR and IRR) in AI2006 compared to AI2010. CONCLUSIONS: The VLSCP was not effective at controlling L. infantum infection in areas where interventions had respectively been carried out for six and four years. However, it is unclear what the consequences in terms of human infection and diseases would be in the absence of the VLSCP. Efforts to improve the effectiveness of control measures remain a necessary priority

Agreement between serological and qPCR results for <i>L. infantum</i> infection in children (n = 559) living in the northwestern region of Belo Horizonte in 2010.

<p>Kappa<0.1.</p><p>Abbreviation: qPCR, quantitative polymerase chain reaction.</p

Parasite load of children remained positive tested by qPCR results at baseline and follow-up.

<p>The samples that tested positive at baseline had a mean concentration of 56.5±33.4 parasites/mL of blood. At follow-up, the mean parasitemia of children who remained positive was 7.8±7.0 parasites/mL (baseline, dark; follow-up, clear).</p

Diagnosis of asymptomatic infection in 199 subjects by qPCR at baseline and 12-month follow-up in Belo Horizonte, Minas Gerais (2009–2010).

<p>Abbreviations: follow-up; qPCR, quantitative polymerase chain reaction.</p

Estimate by qPCR of the prevalence of <i>L. infantum</i> infection in children living in the northwestern region of Belo Horizonte (n = 1875).

<p>Abbreviations: CI, confidence interval; qPCR, quantitative polymerase chain reaction.</p