Implementation of genomic and spatial surveillance of visceral leishmaniasis (VL) in the state of São Paulo. Contributions to the Review of VL Surveillance and Control Actions in Brazil

• Grant number: 24/15388-9
• Support Opportunities: Research Grants - Research in Public Policies
• Start date: June 01, 2025
• End date: May 31, 2029
• Field of knowledge: Biological Sciences - Parasitology - Protozoology of Parasites
• Principal Investigator: José Eduardo Tolezano
• Grantee: José Eduardo Tolezano
• Host Institution: Instituto Adolfo Lutz (IAL). Coordenadoria de Controle de Doenças (CCD). Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil
• Associated researchers: Denise Maria Bussoni Bertollo ; Elisa Cupolillo ; Helena Hilomi Taniguchi ; Juliana Galera Castilho Kawai ; Juliana Mariotti Guerra ; LOURDES APARECIDA ZAMPIERI D ANDREA ; Mariana Côrtes Boité ; Patricia de Fatima Florencio Henschel ; Patricia Sayuri Silvestre Matsumoto ; Roberto Mitsuyoshi Hiramoto ; Samanta Etel Treiger Borborema de Carvalho ; Virgínia Bodelão Richini Pereira

Abstract

In São Paulo, since the first autochthonous case of Visceral Leishmaniasis (VL) in 1998, the disease has spread in a spatial pattern related to highways, railways, and the movement of people in urban areas. By 2022, autochthonous human VL had been reported in 119 municipalities in São Paulo, canine VL in 187, and the vector, Lutzomyia longipalpis, in 209. Regarding the agent of human and canine VL-Leishmania infantum-recent literature reports greater genetic heterogeneity than previously assumed, primarily represented by the occurrence of a homozygous deletion of four genes from the tetrassomal chromosome 31. This trait has been described as a genetic marker associated with a ninefold increase in treatment failure with Miltefosine, a drug approved for treating infected dogs. Data also point to differences in the transmissibility and virulence of parasites with (DEL) or without (Non-DEL) the deletion, suggesting that this genomic trait is also an important marker for clinical and epidemiological monitoring of VL. Recently, we identified in São Paulo both DEL and Non-DEL populations of L. infantum, as well as a third pattern indicating mixed infection or genetic recombination. Considering the high prevalence of canine VL across different regions of São Paulo; considering the interaction of IALutz with the Ministry of Health as a partnering institution and CLIOC-FIOCRUZ as an associated institution, the objectives of this proposal are directed towards the Public Policy on VL Surveillance and Control: i) to monitor the diversity of L. infantum in the state; ii) to conduct genomic and spatial characterization of L. infantum; iii) to implement strategies for monitoring VL agents in the state; iv) to provide training and technology transfer from CLIOC to the IALutz Network and to train human resources, including researchers, staff, and graduate students; v) to transfer knowledge to support the revision of this public policy in Brazil. (AU)