Occurrence of Lutzomyia longipalpis andhuman and canine cases of visceral leishmaniasis and evaluation of their expansion in the Northwest region of the State of São Paulo, Brazil

Abstract: INTRODUCTION This paper aims to describe the dispersion of Lutzomyia longipalpis and the autochthonous occurrence of visceral leishmaniasis (VL) in the Northwest region of the State of São Paulo between 2007 and 2013 and to analyze their expansion. METHODS Information about the vector and associated cases was described using maps. The incidence, mortality, and lethality of human visceral leishmaniasis (HVL) were calculated. In municipalities in which more than one HVL case occurred, incidences were calculated according to census sector, and spatial and spatiotemporal clusters were identified. RESULTS The first case of HVL was reported in the municipality of Jales in 2007. By 2013, the vector and the disease had expanded from west to east, with the vector being detected in 29 municipalities. A total of 11 municipalities had cases of canine visceral leishmaniasis (CVL), and six had cases of HVL. Vector expansion occurred by vicinity with previously infested municipalities, and the expansion of VL was related to the major highways and the capital municipalities of the micro-regions in the study area. The highest incidence of HVL occurred in children between 0-4 years old, and the highest mortality and lethality occurred among persons aged 60 and older. The occurrence of HLV was more intense in the peripheral areas of municipalities with the disease. CONCLUSIONS The findings of this study may be useful for improving VL surveillance and control activities by slowing VL expansion and/or mitigating VL effects when they occur.

Estudo da expansão da Leishmaniose Visceral no estado de São Paulo e de fatores intervenientes / Study the expansion of visceral leishmaniasis in São Paulo state and intervening factors

INTRODUÇÃO: Leishmaniose visceral (LV) é uma doença negligenciada que afeta milhões de pessoas no mundo e que constitui um grave problema de saúde pública. OBJETIVOS: Descrever no tempo e no espaço, a dispersão de Lutzomyia longipalpis e a expansão da LV no estado de São Paulo (SP); identificar fatores associados a estes processos. MÉTODOS: Foram realizados estudos descritivos, ecológicos e de análise de sobrevida. Informações sobre o vetor e os casos foram obtidas na Superintendência de Controle de Endemias e no Sistema de Informações de Agravos de Notificação para o período de 1997 a 2014. A área de estudo foi composta pelos 645 municípios de SP. Foram produzidos mapas temáticos e de fluxo e calcularam-se incidência, mortalidade e letalidade por LV em humanos (LVH). Utilizou-se a técnica de análise de sobrevida (Curvas de Kaplan-Meier e Regressão de Cox) para a identificação de fatores associados à dispersão do vetor e expansão da LV. RESULTADOS: A partir da detecção de Lu. longipalpis em Araçatuba em 1997, deram-se a ocorrência do primeiro caso canino (LVC) (1998) e o primeiro caso humano (LVH) autóctones (1999) em SP. Até 2014, foi detectada a presença do vetor em 173 (26,8 por cento ) municípios, LVC em 108 (16,7 por cento ) e LVH em 84 (13 por cento ). A expansão dos três fenômenos ocorreu no sentido noroeste para sudeste e se deram a velocidades constantes

INTRODUCTION: Visceral leishmaniasis (VL) is a neglected disease that affects millions of people worldwide and is a serious public health problem. To describe in time and space, Lutzomyia longipalpis dispersion and expansion of LV in São Paulo (SP); identify factors associated with these procedures. METHODS: We conducted descriptive studies, ecological and survival analysis. Vector information and the cases were obtained from the Superintendency of Endemic Disease Control and System for Noticeable Diseases Information for the period from 1997 to 2014. The study area was composed of 645 municipalities of SP. They were produced thematic and flow maps and were calculated incidence, mortality and lethality by LV in humans (LVH). We used the survival analysis technique (Kaplan-Meier curves and Cox regression models) for the identification of factors associated with vector dispersion and expansion of the LV. RESULTS: From Lu. longipalpis detection in Araçatuba in 1997, given the occurrence of the first canine case (LVC) (1998) and the first autochthonous human (LVH) case (1999) in SP. By 2014, the vector presence in 173 was detected (26.8 per cent ) municipalities, LVC in 108 (16.7 per cent ) and LVH in 84 (13 per cent ). The expansion of the three phenomena occurred in the northwest towards the southeast and gave constant speeds

Temporal, spatial and spatiotemporal analysis of the occurrence of visceral leishmaniasis in humans in the City of Birigui, State of São Paulo, from 1999 to 2012

Introduction In 1999, Birigui and Araçatuba were the first municipalities in the State of São Paulo to present autochthonous cases of visceral leishmaniasis in humans (VLH). The aim of this study was to describe the temporal, spatial and spatiotemporal behaviors of VLH in Birigui. Methods Secondary data were obtained from the Notifiable Diseases Information System from 1999 to 2012. The incidence, mortality and case fatality rates by sex and age were calculated. The cases of VLH were geocoded and grouped according to census tracts. Local empirical Bayesian incidence rates were calculated. The existence of spatial and spatiotemporal clusters was investigated using SaTScan software. Results There were 156 confirmed cases of autochthonous VLH. The incidence rate was higher in the 0-4-year-old children, and the mortality and case fatality rates were higher in people aged 60 years and older. The peaks of incidence occurred in 2006 and 2011. The Bayesian rates identified the presence of VLH in all of the census tracts in the municipality; however, spatial and spatiotemporal clusters were found in the central area of the municipality. Conclusions Birigui, located in the Araçatuba region, has recently experienced increasing numbers of VLH cases; this increase is contrary to the behavior observed over the entire region, which has shown a decreasing trend in the number of VLH cases. The observations that the highest incidence is in children 0-4 years old and the highest mortality is in people 60 years and older are in agreement with the expected patterns of VLH. .

Introducao e expansao da Leishmaniose visceral americana em humanos no estado de Sao Paulo, 1999-2011 / Introduccion y expansion de la Leishmaniosis visceral americana en humanos en el estado de Sao Paulo, 1999-2011. / Introduction and expansion of human American visceral leishmaniasis in the state of Sao Paulo, Brazil, 1999-2011

OBJETIVO : Analisar a expansão da ocorrência de leishmaniose visceral americana em humanos e identificar localidades prioritárias para o desenvolvimento de ações de vigilância e controle. MÉTODOS : A área de estudo constituiu-se dos 316 municípios do estado de São Paulo pertencentes às cinco regiões de saúde com ocorrência da leishmaniose visceral americana em humanos, utilizando os casos autóctones e óbitos, com ano de notificação e município de ocorrência. Calcularam-se taxas de incidência e de mortalidade e letalidade por município, por região e para a área de estudo. Utilizaram-se o estimador bayesiano empírico para obtenção de taxas de incidência e de mortalidade bayesianas locais para cada município e a krigagem para visualização da distribuição espacial das temperaturas e das precipitações pluviométricas. RESULTADOS : Foram detectados 73 municípios com transmissão da doença. As primeiras ocorrências deram-se em áreas com maiores temperaturas e menores pluviosidades, mas sua disseminação também ocorreu em áreas menos quentes e mais úmidas. A expansão da leishmaniose visceral americana em humanos apresentou um eixo principal de disseminação no sentido noroeste para sudeste, acompanhando a rodovia Marechal Rondon e o gasoduto Bolívia-Brasil, e um eixo secundário, na direção norte-sul, acompanhando a malha rodoviária. As taxas de incidência, segundo regiões de saúde, apresentaram um pico seguido de queda, com exceção da região de São José do Rio Preto. Observou-se maior concentração de municípios com altas taxas de incidência e mortalidade nas regiões de saúde de Araçatuba, Presidente ...

OBJETIVO Analizar la expansión de la ocurrencia de leishmaniosis visceral americana en humanos en el estado de Sao Paulo e identificar municipios prioritarios para el desarrollo de acciones de vigilancia y control. MÉTODOS El área de estudio estaba conformada por 316 municipios del estado pertenecientes a cinco regiones de salud con ocurrencia de la enfermedad, utilizando los casos autóctonos y óbitos de leishmaniosis visceral americana en humanos, con año de notificación y municipio de ocurrencia. Se calcularon las tasas de incidencia y de mortalidad y letalidad por municipio, por región y para el área de estudio. Se utilizaron el estimador bayesiano empírico para la obtención de tasas de incidencia y de mortalidad bayesianas locales para cada municipio y la krigagem para visualización de la distribución espacial de las temperaturas y de las precipitaciones pluviométricas. RESULTADOS Se detectaron 73 municipios con transmisión de la enfermedad. Las primeras ocurrencias se presentaron en áreas con mayores temperaturas y menores pluviosidades, sin embargo su diseminación también ocurrió en áreas menos calientes y más húmedas. La expansión de la leishmaniosis visceral americana en humanas presentó un eje principal de diseminación en el sentido noroeste hacia sureste, acompañando la carretera Marechal Rondon y el gasoducto Bolivia-Brasil, y un eje secundario, en la dirección norte-sur, acompañando la red vial. Las tasas de incidencia, según regiones de salud, presentaron un pico seguido por una disminución, con excepción de la región Sao José do Rio Preto. Se observó mayor concentración de municipios con altas tasas de incidencia y mortalidad en las regiones de salud de Araçatuba, Presidente Prudente y Marília. CONCLUSIONES Posibles factores determinantes ...

OBJECTIVE : To analyze the spread of human American visceral leishmaniasis and identify the key municipalities for developing surveillance and control activities. METHODS : The area of the study was composed of the 316 municipalities in the state of Sao Paulo belonging to the five health districts in which human American visceral leishmaniasis occurs, using data on autochthonous cases and deaths according to the reporting year and municipality in which the death occurred. The incidence, mortality and case fatality rates for each municipality and for the entire area were calculated. An empirical Bayes estimator was used to calculate the local Bayesian incidence and rates of mortality per municipality, and Kriging was used to visualize the spatial distribution of temperature and rainfall. RESULTS : A total of 73 municipalities with transmission of the disease were identified. Human American visceral leishmaniasis was first detected in areas with higher temperatures and lower rainfall, but it also spread in cooler and wetter areas. The expansion of human American visceral leishmaniasis occurred along a main axis of dissemination, from Northwest to Southeast, following the Marechal Rondon highway and the Bolivia-Brazil gas pipeline, and along a secondary axis that was derived from the main axis, which runs both North and South, following the highway network. Rates of incidence according to health district exhibit a peak, followed by a fall, except the Sao Jose do Rio Preto region. Higher concentrations of municipalities with high incidence and mortality rates were observed in the Araçatuba, Presidente Prudente and Marília health districts. CONCLUSIONS : This study indicates possible determinants of the spread of disease, including the Marechal Rondon highway and the construction of the Bolivia-Brazil gas pipeline. Climatic factors seemed to play no role in the spread. The use of spatial analysis techniques allowed the ...