Evaluation of chemical spraying and environmental management efficacy in areas with minor previous application of integrated control actions for visceral leishmaniasis in Brazil.

Leishmaniases are vector-borne diseases that are transmitted to humans through the bite of Leishmania-infected phlebotomine sand flies (Diptera:Psychodidae). The main proved vector of visceral leishmaniais (VL) in the New World - Lutzomyia longipalpis - is well-adapted to urban areas and has extensive distribution within the five geographical regions of Brazil. Integrated public health actions directed for the vector, domestic reservoir and humans for the control of VL are preferentially applied in municipalities with higher epidemiological risk of transmission. In this study, we evaluated the individual impact of two main vector control actions - chemical spraying and environmental management - in two districts with no reported cases of human VL. Although belonging to an endemic municipality for VL in Brazil, the integrated control actions have not been applied in these districts due to the absence of human cases. The number of L. longipalpis captured in a two-year period was used as indicator of the population density of the vector. After chemical spraying a tendency of reduction in L. longipalpis was observed but with no statistical significance compared to the control. Environmental management was effective in that reduction and it may help in the control of VL by reducing the population density of the vector in a preventive and more permanent action, perhaps associated with chemical spraying.

Avaliação das atividades de controle da leishmaniose visceral em Belo Horizonte, Minas Gerais, 2006-2011 / Evaluation of visceral leishmaniasis control activities in Belo Horizonte, Minas Gerais, Brazil, 2006-2011 / Evaluación de las actividades para el control de la leishmaniasis visceral en Belo Horizonte, Minas Gerais, 2006-2011

OBJETIVO: avaliar as atividades de controle da leishmaniose visceral (LV) em Belo Horizonte-MG, Brasil. MÉTODOS: estudo descritivo para avaliação do Programa de Vigilância e Controle da Leishmaniose Visceral pautado em seus objetivos; utilizaram-se dados dos Sistemas de Informação de Controle de Zoonoses e de Agravos de Notificação. RESULTADOS: entre 2007 e 2011, verificou-se adequação da estratégia de controle do reservatório com aumento da cobertura de áreas priorizadas (23,4%) e da população canina examinada (43,3%), eutanásia dos cães sororreagentes superior a 85,0% e redução de 47,8% na soroprevalência canina; no período 2008-2011, observou-se redução na incidência de casos humanos de 7,2 para 3,9/100 mil habitantes; não houve ampliação da cobertura de áreas priorizadas para o controle do vetor. CONCLUSÃO: os indicadores de resultados demonstraram o alcance dos objetivos do programa, com diferente adequação entre as estratégias de controle; a complexidade da intervenção, porém, indica a necessidade de revisão das ações propostas.

OBJECTIVE: to evaluate visceral leishmaniasis (VL) control activities in Belo Horizonte-MG, Brazil. METHODS: this was a descriptive study to evaluate VL control compliance with the objectives of the Brazilian Health Ministry's VL Control Program; data were collected from the Belo Horizonte Zoonosis Control and Notifiable Disease Information Systems. RESULTS: between 2007-2011 the VL reservoir control strategy was adjusted to increase coverage of prioritized areas (23.4%) and coverage of the examined canine population (43.3%); more than 85.0% of seropositive dogs were put down; 47.8% reduction in canine seroprevalence. Between 2008-2011, human case incidence decreased from 7.2 to 3.9/100,000 inhabitants. There was no expansion of coverage in areas prioritized for vector control. CONCLUSION: program objectives were achieved, although adjustments differed between control strategies. However, the intervention's complexity indicates the need to review the proposed measures.

OBJETIVO: evaluar las actividades de control de leishmaniasis visceral (LV) en Belo Horizonte-MG, Brasil. MÉTODOS: estudio descriptivo para evaluar el Programa de Vigilancia y Control de LV, pautado en sus objetivos; utilizamos datos de los Sistemas de Información de Control de Zoonosis y Enfermedades de notificación obligatoria. RESULTADOS: entre 2007 y 2011, hubo una adecuación de la estrategia de control de reservorios, con un aumento de la cobertura de las áreas prioritarias (23,4%) y de la población canina (43,3%); eutanasia de canes seropositivos, superior a 85% y reducción de 47,8% en la seroprevalencia canina; observamos una reducción en la incidencia de casos humanos de 7,2 a 3,9/100.000, entre 2008 y 2011; no hubo expansión de la cobertura de áreas prioritarias para el control de vectores. CONCLUSIÓN: los resultados mostraron que los objetivos del programa se habían alcanzado, con diferente adecuación entre las estrategias de control; la complejidad de la intervención indica la necesidad de revisión de las acciones propuestas.

Epidemiological aspects of vector, parasite, and domestic reservoir in areas of recent transmission and no reported human cases of visceral leishmaniasis in Brazil.

About 97% of the human cases of the American visceral leishmaniasis (VL) occur in Brazil. In the last few years, the disease expanded to medium- and large-sized cities, in which surveillance and control actions have been intensified, in an effort to control VL spreading. Our two-year study was conducted in Belo Horizonte, the sixth most populous city in Brazil, which is endemic for VL. We focused in two particular districts of recent transmission of the disease, with no reported human cases and submitted to minor surveillance and control actions. Our aim was to draw an epidemiological profile of the local situation concerning Lutzomyia vector, Leishmania parasites, and the main domestic reservoirs (dogs). Lutzomyia longipalpis comprised 96.5% of the total phlebotomine sand flies captured and displayed an expressive minimal infection rate by Leishmania infantum (16.7%). Positive correlations were found between the population densities of L. longipalpis, rainfall and temperature. L. infantum was also detected in the cortelezzii complex and, for the first time, in Lutzomyia lloydi. Leishmania braziliensis, an etiological agent of the American cutaneous leishmaniasis, was also identified in L. longipalpis. Among the 1408 dogs serologically tested by standard enzyme-linked and fluorescence immune assays (ELISA/IFA) 3.6% were positive for VL. L. infantum DNA and Leishmania parasites were identified in 100% and 72.5% of the seropositive dogs, respectively. The co-positivity of other diagnostic tests for VL-Leishmania-nested PCR, imprint and myeloculture-was compared to the standard serology. Both symptomatic or asymptomatic dogs displayed an equal average number of positive diagnostic tests for VL. The districts studied display favorable conditions for the rapid spreading of human infection, in terms of L. longipalpis population density, and presence of L. infantum in both vector and main reservoir.

Information system and geographic information system tools in the data analyses of the control program for visceral leishmaniases from 2006 to 2010 in the sanitary district of venda nova, belo horizonte, minas gerais, Brazil.

The aim of this paper is to report a brief history of control actions for Visceral Leishmaniasis (VL) from 2006 to 2010 in the Sanitary District (DS) of Venda Nova, Belo Horizonte, Minas Gerais, Brazil, focusing on the use of information systems and Geographic Information System (GIS) tools. The analyses showed that the use of an automated database allied with geoprocessing tools may favor control measures of VL, especially with regard to the evaluation of control actions carried out. Descriptive analyses of control measures allowed to evaluating that the information system and GIS tools promoted greater efficiency in making decisions and planning activities. These analyses also pointed to the necessity of new approaches to the control of VL in large urban centers.

[Assessment of knowledge and preventive attitudes concerning visceral leishmaniasis in Belo Horizonte, Minas Gerais State, Brazil]. / Avaliação do nível de conhecimento e de atitudes preventivas da população sobre a leishmaniose visceral em Belo Horizonte, Minas Gerais, Brasil.

The main objective of this study was to evaluate knowledge concerning visceral leishmaniasis and attitudes used to prevent the disease in Belo Horizonte, Minas Gerais State, Brazil, in 2006. A case-control study was conducted, with home visits and a questionnaire. The odds ratio was calculated, comparing 82 cases of human visceral leishmaniasis in 2004 and 164 controls (neighbors of cases). The disease was more frequent in children (OR=109.77). Visceral leishmaniasis was 2.57 times more likely in males than in females. Overall schooling level was low (68.3% of subjects had not completed secondary school). Half of the cases did not know what visceral leishmaniasis was, and only 1.2% could identify the vector. Having basic knowledge of visceral leishmaniasis reduced the odds of acquiring the disease by 2.24 times. Keeping the house clean and taking pet dogs to the veterinarian reduced the risk by 1.94 times. In Belo Horizonte, the population's level of knowledge on visceral leishmaniasis is superficial, and preventive attitudes are inaccurate.

Avaliação do nível de conhecimento e de atitudes preventivas da população sobre a leishmaniose visceral em Belo Horizonte, Minas Gerais, Brasil / Assessment of knowledge and preventive attitudes concerning visceral leishmaniasis in Belo Horizonte, Minas Gerais State, Brazil

Objetivou-se avaliar o nível de conhecimento e algumas atitudes preventivas em relação à leishmaniose visceral em Belo Horizonte, Minas Gerais, Brasil, em 2006. Foi feito um estudo de caso-controle, com visitas domiciliares e questionário semi-estrurado. Comparou-se dois grupos: (1) 82 casos humanos de leishmaniose visceral ocorridos em 2004 e (2) 164 controles, constituídos por vizinhos dos casos. A leishmaniose visceral acometeu mais em crianças, com aumento do risco de contrair leishmaniose visceral de 109,77 vezes para menores de dez anos. O homem demonstrou ter 2,57 vezes mais chances de adoecer que a mulher. A escolaridade da população mostrou-se baixa (68,3 por cento não completaram o ensino médio). Cinqüenta por cento dos casos desconheciam-na quando foram infectados e apenas 1,2 por cento conhecia o vetor. Conhecer algo sobre a leishmaniose visceral minimizou o risco de adoecer em 2,24 vezes. Quanto às atitudes de proteção, o risco de se contrair leishmaniose visceral diminui em 1,94 vez para pessoas que mantêm limpos os domicílios ou que levam o cão ao veterinário. Em Belo Horizonte, o conhecimento da população perante a leishmaniose visceral é superficial e as atitudes preventivas inespecíficas.

The main objective of this study was to evaluate knowledge concerning visceral leishmaniasis and attitudes used to prevent the disease in Belo Horizonte, Minas Gerais State, Brazil, in 2006. A case-control study was conducted, with home visits and a questionnaire. The odds ratio was calculated, comparing 82 cases of human visceral leishmaniasis in 2004 and 164 controls (neighbors of cases). The disease was more frequent in children (OR = 109.77). Visceral leishmaniasis was 2.57 times more likely in males than in females. Overall schooling level was low (68.3 percent of subjects had not completed secondary school). Half of the cases did not know what visceral leishmaniasis was, and only 1.2 percent could identify the vector. Having basic knowledge of visceral leishmaniasis reduced the odds of acquiring the disease by 2.24 times. Keeping the house clean and taking pet dogs to the veterinarian reduced the risk by 1.94 times. In Belo Horizonte, the population's level of knowledge on visceral leishmaniasis is superficial, and preventive attitudes are inaccurate.