title: Multibacillary leprosy by population groups in Brazil: Lessons from an observational study.
abstract: Leprosy remains an important public health problem in Brazil where 28,761 new cases were diagnosed in 2015, the second highest number of new cases detected globally. The disease is caused by Mycobacterium leprae, a pathogen spread by patients with multibacillary (MB) leprosy. This study was designed to identify population groups most at risk for MB disease in Brazil, contributing to new ideas for early diagnosis and leprosy control.
  
  
  
  A national databank of cases reported in Brazil (2001-2013) was used to evaluate epidemiological characteristics of MB leprosy. Additionally, the databank of a leprosy reference center was used to determine factors associated with higher bacillary loads.
  
  
  
  A total of 541,090 cases were analyzed. New case detection rates (NCDRs) increased with age, especially for men with MB leprosy, reaching 44.8 new cases/100,000 population in 65-69 year olds. Males and subjects older than 59 years had twice the odds of MB leprosy than females and younger cases (OR = 2.36, CI95% = 2.33-2.38; OR = 1.99, CI95% = 1.96-2.02, respectively). Bacillary load was higher in male and in patients aged 20-39 and 40-59 years compared to females and other age groups. From 2003 to 2013, there was a progressive reduction in annual NCDRs and an increase in the percentage of MB cases and of elderly patients in Brazil. These data suggest reduction of leprosy transmission in the country.
  
  
  
  Public health policies for leprosy control in endemic areas in Brazil should include activities especially addressed to men and to the elderly in order to further reduce M. leprae transmission.
authors.affiliation: Pós-Graduação em Medicina Tropical, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, Brazil.|Hospital Giselda Trigueiro, Secretaria Estadual de Saúde, Natal, RN, Brazil.|Instituto de Medicina Tropical do Rio Grande do Norte, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil.
authors.forename: Mauricio Lisboa
authors.identifier: 0000-0003-4932-3137
authors.initials: ML
authors.lastname: Nobre
authors.affiliation: Centro de Desenvolvimento Tecnológico em Saúde, Fiocruz, Rio de Janeiro, RJ, Brazil.
authors.forename: Ximena
authors.initials: X
authors.lastname: Illarramendi
authors.affiliation: Division of Infectious Diseases and Center for Global Health, Weill Cornell Medical College, New York, NY, United States of America.
authors.forename: Kathryn Margaret
authors.initials: KM
authors.lastname: Dupnik
authors.affiliation: Laboratório de Hanseníase, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, Brazil.
authors.forename: Mariana de Andrea
authors.initials: MA
authors.lastname: Hacker
authors.affiliation: Laboratório de Hanseníase, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, Brazil.
authors.forename: José Augusto da Costa
authors.initials: JA
authors.lastname: Nery
authors.affiliation: Instituto de Medicina Tropical do Rio Grande do Norte, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil.|Departamento de Bioquímica, Centro de Biociências, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil.|Instituto Nacional de Ciência e Tecnologia de Doenças Tropicais, INCT-DT, Natal, RN, Brazil.
authors.forename: Selma Maria Bezerra
authors.initials: SM
authors.lastname: Jerônimo
authors.affiliation: Laboratório de Hanseníase, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, Brazil.
authors.forename: Euzenir Nunes
authors.initials: EN
authors.lastname: Sarno
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D056006:Leprosy, Multibacillary / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D044382:Population Groups; D018570:Risk Assessment; D012307:Risk Factors; D055815:Young Adult