Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Jun 1;156(6):640-648.
doi: 10.1001/jamadermatol.2020.0653.

Incidence of and Factors Associated With Leprosy Among Household Contacts of Patients With Leprosy in Brazil

Camila Silveira Silva Teixeira  1   2 , Júlia Moreira Pescarini  1 , Flávia Jôse Oliveira Alves  1   2 , Joilda Silva Nery  2 , Mauro Niskier Sanchez  1   3 , Carlos Teles  1 , Maria Yury Travassos Ichihara  1 , Anna Ramond  4 , Liam Smeeth  5   6 , Maria Lucia Fernandes Penna  7 , Laura Cunha Rodrigues  4 , Elizabeth B Brickley  4 , Gerson Oliveira Penna  3   8 , Maurício Lima Barreto  1   2 , Rita de Cássia Ribeiro Silva  1   9
Affiliations

Incidence of and Factors Associated With Leprosy Among Household Contacts of Patients With Leprosy in Brazil

Camila Silveira Silva Teixeira et al. JAMA Dermatol. .

Abstract

Importance: Despite progress toward reducing global incidence, leprosy control remains a challenge in low- and middle-income countries.

Objective: To estimate new case detection rates of leprosy among household contacts of patients with previously diagnosed leprosy and to investigate its associated risk factors.

Design, setting, and participants: This population-based cohort study included families registered in the 100 Million Brazilian Cohort linked with nationwide registries of leprosy; data were collected from January 1, 2007, through December 31, 2014. Household contacts of patients with a previous diagnosis of leprosy from each household unit were followed up from the time of detection of the primary case to the time of detection of a subsequent case or until December 31, 2014. Data analysis was performed from May to December 2018.

Exposures: Clinical characteristics of the primary case and sociodemographic factors of the household contact.

Main outcomes and measures: Incidence of leprosy, estimated as the new case detection rate of leprosy per 100 000 household contacts at risk (person-years at risk). The association between occurrence of a subsequent leprosy case and the exposure risk factors was assessed using multilevel mixed-effects logistic regressions allowing for state- and household-specific random effects.

Results: Among 42 725 household contacts (22 449 [52.5%] female; mean [SD] age, 22.4 [18.5] years) of 17 876 patients detected with leprosy, the new case detection rate of leprosy was 636.3 (95% CI, 594.4-681.1) per 100 000 person-years at risk overall and 521.9 (95% CI, 466.3-584.1) per 100 000 person-years at risk among children younger than 15 years. Household contacts of patients with multibacillary leprosy had higher odds of developing leprosy (adjusted odds ratio [OR], 1.48; 95% CI, 1.17-1.88), and the odds increased among contacts aged 50 years or older (adjusted OR, 3.11; 95% CI, 2.03-4.76). Leprosy detection was negatively associated with illiterate or preschool educational level (adjusted OR, 0.59; 95% CI, 0.38-0.92). For children, the odds were increased among boys (adjusted OR, 1.70; 95% CI, 1.20-2.42).

Conclusions and relevance: The findings in this Brazilian population-based cohort study suggest that the household contacts of patients with leprosy may have increased risk of leprosy, especially in households with existing multibacillary cases and older contacts. Public health interventions, such as contact screening, that specifically target this population appear to be needed.

PubMed Disclaimer

Conflict of interest statement

Conflict of Interest Disclosures: Ms Teixeira reported receiving grants and personal fees from Conselho Nacional das Fundações Estaduais de Amparo à Pesquisa (CONFAP)/Economic and Social Research Council (ESRC)/Medical Research Council (MRC)/Biotechnology and Biological Sciences Research Council (BBSRC)/Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)/Fundação de Apoio à Pesquisa do Distrito Federal (FAPDF) and from the Wellcome Trust; and reported receiving personal fees from Capes during the conduct of the study. Dr Pescarini reported receiving grants and personal fees from CONFAP/ESRC/MRC/BBSRC/CNPq/FAPDF and from the Wellcome Trust during the conduct of the study; and reported receiving grants from the Medical Research Council, the Wellcome Trust, and the Bill and Melinda Gates Foundation. Dr Ichihara reported receiving grants from Ministerio da Ciência, Tecnologia, Inovações e Comunicações (MCTI)/Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)/Ministério da Saúde (MS)/Secretaria de Ciência, Tecnologia e Insumos Estratégicos do Ministério da Saúde (SCTIE)/Departamento de Ciência e Tecnologia (Decit)/Bill & Melinda Gates Foundation during the conduct of the study. Dr Ramond reported receiving grants from MRC during the conduct of the study. Dr G. Penna reported receiving grants from FAPDF during the conduct of the study. Dr Brickley reported receiving grants from the MRC (MR/N017250/1) during the conduct of the study. Dr Barreto reported receiving grants from CONFAP/ESRC/MRC/BBSRC/CNPq/FAPDF and the Wellcome Trust during the conduct of the study. Dr Silva reported receiving grants from CONFAP/ESRC/MRC/BBSRC/CNPq/FAPDF and the Wellcome Trust during the conduct of the study. No other disclosures were reported.

Figures

Figure 1.
Figure 1.. Flowchart
CadUnico indicates Cadastro Unico para Programas Sociais; SINAN, Sistema de Informação de Agravos de Notificação.
Figure 2.
Figure 2.. Cumulative Incidence of Subsequent Leprosy Cases Among Households of Patients With Leprosy
See this image and copyright information in PMC

References

    1. Stolk WA, Kulik MC, le Rutte EA, et al. . Between-country inequalities in the neglected tropical disease burden in 1990 and 2010, with projections for 2020. PLoS Negl Trop Dis. 2016;10(5):e0004560. doi:10.1371/journal.pntd.0004560 - DOI - PMC - PubMed
    1. Pedrosa VL, Dias LC, Galban E, et al. . Leprosy among schoolchildren in the Amazon region: a cross-sectional study of active search and possible source of infection by contact tracing. PLoS Negl Trop Dis. 2018;12(2):e0006261. doi:10.1371/journal.pntd.0006261 - DOI - PMC - PubMed
    1. Le W, Haiqin J, Danfeng H, et al. . Monitoring and detection of leprosy patients in southwest China: a retrospective study, 2010-2014. Sci Rep. 2018;8(1):11407. doi:10.1038/s41598-018-29753-4 - DOI - PMC - PubMed
    1. Fine PE, Sterne JA, Pönnighaus JM, et al. . Household and dwelling contact as risk factors for leprosy in northern Malawi. Am J Epidemiol. 1997;146(1):91-102. doi:10.1093/oxfordjournals.aje.a009195 - DOI - PubMed
    1. Moet FJ, Meima A, Oskam L, Richardus JH. Risk factors for the development of clinical leprosy among contacts, and their relevance for targeted interventions. Lepr Rev. 2004;75(4):310-326. - PubMed

Publication types

MeSH terms