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.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade de São Paulo Escola de Enfermagem Curso de Graduação em EnfermagemUniversidade de São Paulo Faculdade de Saúde Pública Programa de Pós-Graduação em Saúde PúblicaUniversidade Estadual Paulista Júlio de Mesquita Filho Programa de Pós-Graduação em Ciência AnimalRegional de Araçatuba Secretaria de Estado de Saúde de São Paulo Superintendência de Controle de EndemiasSecretaria de Estado de Saúde de São Paulo Superintendência de Controle de Endemias Laboratório de Vetores de São José do Rio PretoUniversidade de São Paulo Faculdade de Saúde Pública Departamento de EpidemiologiaUniversidade Estadual Paulista Júlio de Mesquita Filho Programa de Pós-Graduação em Ciência Anima

Sand fly synthetic sex-aggregation pheromone co-located with insecticide reduces the incidence of infection in the canine reservoir of visceral leishmaniasis: a stratified cluster randomised trial

The predominant sand fly vector of the intracellular parasite Leishmania infantum, that causes human and canine visceral leishmaniasis in the Americas, is Lutzomyia longipalpis. Dogs are the proven reservoir. Vector control tools to reduce transmission suited to this predominantly exophilic vector are lacking. Insecticide-impregnated dog collars protect dogs against infectious bites from sand fly vectors, and result in reductions of new infections in both dogs and humans. However, collars are costly for endemic communities, and alternative approaches are needed. Recently the bulk synthesised sex-aggregation pheromone of male Lu. longipalpis was shown to attract large numbers of conspecific females to lethal pyrethroid insecticides, indicating the potential for use in a vector control application. This study, conducted in Brazil, evaluated the efficacy of this novel lure-and-kill approach to reduce seroconversion and infection incidence with L. infantum in the canine reservoir, in addition to measuring its impact on household abundance of Lu. longipalpis. Deployed in 14 stratified clusters, the outcomes were compared to those attributed to insecticide impregnated collars fitted to dogs in another 14 clusters; each intervention was compared to 14 clusters that received placebo treatments. The beneficial effects of the lure-and-kill method were most noticeable on confirmed infection incidence and clinical parasite loads, and in reducing sand fly abundance. The overall effect of the two interventions were not statistically dissimilar, though the confidence intervals were broad. We conclude that the novel low-cost lure-and-kill approach should be added to the vector control toolbox against visceral leishmaniasis in the Americas

Leishmaniasis-Vector Surveillance and Control in Brazil: A Challenge to Control Programs

This is the first English-language book dedicated to Brazilian sand flies and their medical importance. No other country has so many species of these haematophagous insects as Brazil and their diversity has reached an astonishing level. The book contains comprehensive chapters, written by Brazilian experts on their regional distribution, their ecology and their importance as vectors of pathogens and parasites. Methods for sampling, processing and preserving phlebotomines are reviewed as are perspectives on surveillance and leishmaniasis vector control. A novel classification is presented whose aim is to help investigators identify the species that they are working with more efficiently.Fil: Maia Elkhoury, Ana Nilce S.. Pan American Health Organization; BrasilFil: Albuquerque, Rafaella. Ministry of Health. Communicable Diseases General Office; BrasilFil: Salomón, Oscar Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina. Ministerio de Salud. Instituto Nacional de Medicina Tropical; Argentin