A social network approach for the study of leprosy transmission beyond the household

Carl Kendall*, Ligia Regina Franco Sansigolo Kerr, Jose Garcia Vivas Miranda, Suani Tavares Rubin De Pinho, Roberto Fernandes Silva Andrade, Laura Cunha Rodrigues, Cristiane Cunha Frota, Rosa Maria Salani Mota, Rosa Lívia Freitas De Almeida, Fabio Brito Moreira, Raoni Boaventura Cruz Gomes, Naíla Alves De Almeida, Lucas França, Maria Araci De Andrade Pontes, Hector Gonçalves, Gerson Oliveira Penna, Samira Bührer-Sekula, Alden Klovdahl, Maurício Lima Barreto

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

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Background: Mycobacterium leprae was the first microorganism directly associated with a disease, however, there are still important gaps in our understanding of transmission. Although household contacts are prioritized, there is evidence of the importance of extrahousehold contacts. The goal of this article is to contribute to our understanding of the transmission of leprosy ex-household. Methods: We compare co-location data of 397 leprosy cases and 211 controls drawn from the Centro de Dermatologia Sanitária D. Libânia in Fortaleza, Brazil. We collected lifetime geolocation data related to residence, school attendance and workplace and developed novel methods to establish a critical distance (Rc) for exposure and evaluated the potential for transmission for residence, school and workplace. Results: Our methods provide different threshold values of distance for residence, school and workplace. Residence networks demonstrate an Rc of about 500 m. Cases cluster in workplaces as well. Schools do not cluster cases. Conclusions: Our novel network approach offers a promising opportunity to explore leprosy transmission. Our networks confirm the importance of coresidence, provide a boundary and suggest a role for transmission in workplaces. Schools, on the other hand, do not demonstrate a clustering of cases. Our findings may have programmatic relevance.

Original languageEnglish
Pages (from-to)100-107
Number of pages8
JournalTransactions of the Royal Society of Tropical Medicine and Hygiene
Issue number2
Early online date20 May 2021
Publication statusPublished - 1 Feb 2022
Externally publishedYes

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