title: Spatial clustering and local risk of leprosy in São Paulo, Brazil.
abstract: Although the detection rate is decreasing, the proportion of new cases with WHO grade 2 disability (G2D) is increasing, creating concern among policy makers and the Brazilian government. This study aimed to identify spatial clustering of leprosy and classify high-risk areas in a major leprosy cluster using the SatScan method.
  
  
  
  Data were obtained including all leprosy cases diagnosed between January 2006 and December 2013. In addition to the clinical variable, information was also gathered regarding the G2D of the patient at diagnosis and after treatment. The Scan Spatial statistic test, developed by Kulldorff e Nagarwalla, was used to identify spatial clustering and to measure the local risk (Relative Risk-RR) of leprosy. Maps considering these risks and their confidence intervals were constructed.
  
  
  
  A total of 434 cases were identified, including 188 (43.31%) borderline leprosy and 101 (23.28%) lepromatous leprosy cases. There was a predominance of males, with ages ranging from 15 to 59 years, and 51 patients (11.75%) presented G2D. Two significant spatial clusters and three significant spatial-temporal clusters were also observed. The main spatial cluster (p = 0.000) contained 90 census tracts, a population of approximately 58,438 inhabitants, detection rate of 22.6 cases per 100,000 people and RR of approximately 3.41 (95%CI = 2.721-4.267). Regarding the spatial-temporal clusters, two clusters were observed, with RR ranging between 24.35 (95%CI = 11.133-52.984) and 15.24 (95%CI = 10.114-22.919).
  
  
  
  These findings could contribute to improvements in policies and programming, aiming for the eradication of leprosy in Brazil. The Spatial Scan statistic test was found to be an interesting resource for health managers and healthcare professionals to map the vulnerability of areas in terms of leprosy transmission risk and areas of underreporting.
authors.affiliation: Graduate Program in Public Health Nursing, University of São Paulo at Ribeirão Preto College of Nursing, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Antônio Carlos Vieira
authors.identifier: 0000-0002-7862-1355
authors.initials: AC
authors.lastname: Ramos
authors.affiliation: Graduate Program Interunit Doctoral Program in Nursing, University of São Paulo at Ribeirão Preto College of Nursing, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Mellina
authors.initials: M
authors.lastname: Yamamura
authors.affiliation: Graduate Program in Public Health Nursing, University of São Paulo at Ribeirão Preto College of Nursing, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Luiz Henrique
authors.initials: LH
authors.lastname: Arroyo
authors.affiliation: Graduate Program in Public Health Nursing, University of São Paulo at Ribeirão Preto College of Nursing, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Marcela Paschoal
authors.initials: MP
authors.lastname: Popolin
authors.affiliation: Department of Epidemiology, School of Public Health of the University of São Paulo, São Paulo, São Paulo, Brazil.
authors.forename: Francisco
authors.initials: F
authors.lastname: Chiaravalloti Neto
authors.affiliation: Maternal-Infant Nursing and Public Health Department, University of São Paulo at Ribeirão Preto College of Nursing, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Pedro Fredemir
authors.initials: PF
authors.lastname: Palha
authors.affiliation: Department of Public Health, Federal University of Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil.
authors.forename: Severina Alice da Costa
authors.initials: SA
authors.lastname: Uchoa
authors.affiliation: Department of Nursing, Londrina State University, Londrina, Paraná, Brazil.
authors.forename: Flávia Meneguetti
authors.initials: FM
authors.lastname: Pieri
authors.affiliation: Maternal-Infant Nursing and Public Health Department, University of São Paulo at Ribeirão Preto College of Nursing, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Ione Carvalho
authors.initials: IC
authors.lastname: Pinto
authors.affiliation: Department of Neurosciences and Behavioral Sciences, Ribeirão Preto Medical School of the University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Regina Célia
authors.initials: RC
authors.lastname: Fiorati
authors.affiliation: Graduate Program Interunit Doctoral Program in Nursing, University of São Paulo at Ribeirão Preto College of Nursing, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Ana Angélica Rêgo
authors.initials: AAR
authors.lastname: de Queiroz
authors.affiliation: Graduate Program Interunit Doctoral Program in Nursing, University of São Paulo at Ribeirão Preto College of Nursing, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Aylana de Souza
authors.initials: AS
authors.lastname: Belchior
authors.affiliation: Graduate Program Interunit Doctoral Program in Nursing, University of São Paulo at Ribeirão Preto College of Nursing, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Danielle Talita
authors.initials: DT
authors.lastname: Dos Santos
authors.affiliation: Graduate Program Interunit Doctoral Program in Nursing, University of São Paulo at Ribeirão Preto College of Nursing, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Maria Concebida da Cunha
authors.initials: MC
authors.lastname: Garcia
authors.affiliation: Graduate Program in Public Health Nursing, University of São Paulo at Ribeirão Preto College of Nursing, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Juliane de Almeida
authors.initials: JA
authors.lastname: Crispim
authors.affiliation: Graduate Program in Public Health Nursing, University of São Paulo at Ribeirão Preto College of Nursing, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Luana Seles
authors.initials: LS
authors.lastname: Alves
authors.affiliation: Graduate Program in Public Health Nursing, University of São Paulo at Ribeirão Preto College of Nursing, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Thaís Zamboni
authors.initials: TZ
authors.lastname: Berra
authors.affiliation: Maternal-Infant Nursing and Public Health Department, University of São Paulo at Ribeirão Preto College of Nursing, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Ricardo Alexandre
authors.initials: RA
authors.lastname: Arcêncio
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D005260:Female; D006801:Humans; D007223:Infant; D007918:Leprosy / Q000453:epidemiology* / Q000635:transmission; D008297:Male; D008875:Middle Aged; D018570:Risk Assessment; D062206:Spatial Analysis; D019371:Topography, Medical; D055815:Young Adult