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Temporal and Spatial Analysis of Vector-Tick Borne Spotted Fever in the State of São Paulo
by
, , ,
Daniele Rosa Xavier de Melo
1,*
,
Michellin Pereira de Albuquerque
1,
Fabricio dos Santos Menezes
2,
Sílvia von Tiesenhausen de Sousa-Carmo
3 and
Adriano Pinter
1,4 1
Faculdade de Saúde Pública, Universidade de São Paulo, São Paulo 01246-904, SP, Brazil
2
Departamento de Educação em Saúde, Universidade Federal de Sergipe, Lagarto 49400-000, SE, Brazil
3
Centro de Informações de Vigilância Epidemiológica, Secretaria de Estado da Saúde de São Paulo, São Paulo 01246-000, SP, Brazil
4
Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo 05508-270, SP, Brazil
*
Author to whom correspondence should be addressed.
Zoonotic Dis. 2026, 6(1), 2; https://doi.org/10.3390/zoonoticdis6010002
Submission received: 29 October 2025
/
Revised: 16 December 2025
/
Accepted: 4 January 2026
/
Published: 9 January 2026
Simple Summary
Brazilian spotted fever (BSF) is a tick-borne acute febrile disease that can be lethal to humans, caused by Rickettsia rickettsii. This is a temporal study with secondary data on confirmed human BSF cases of vector-tick borne in the State of São Paulo. In Amblyomma sculptum areas, incidence and mortality increased significantly between 2007 and 2015 (p-value < 0.05). In Amblyomma aureolatum areas, incidence decreased (p-value < 0.05), but mortality remained stable. Lethality was higher in A. aureolatum-associated cases. Most patients were hospitalized near the probable site of infection. Patterns varied markedly by vector tick species, with substantially higher mortality in A. aureolatum areas. These results reinforce the need for vector-specific BSF surveillance and regionally tailored public health interventions in São Paulo.
Abstract
Brazilian spotted fever (BSF) is a tick-borne acute febrile disease that can be lethal to humans, caused by the bacterium Rickettsia rickettsii. In the State of São Paulo, transmission occurs mainly through two tick species: Amblyomma sculptum and Amblyomma aureolatum. We analyzed trends in BSF incidence and mortality in relation to the spatial distribution of these vector species in the State of São Paulo from 2007 to 2017 and evaluated clinical outcomes according to hospitalization location. In A. sculptum areas, incidence and mortality showed significant increasing trends between 2007 and 2015 (p-value < 0.05). In contrast, A. aureolatum areas exhibited a significant decrease in incidence (p-value < 0.05), while mortality remained stable throughout the study period. Lethality was substantially higher in cases associated with A. aureolatum than in those linked to A. sculptum (67.1% versus 55.0%, p-value = 0.037). Most patients received care in hospitals located near the probable site of infection. Incidence and mortality patterns differed sharply between vector-specific areas, with notably higher mortality in A. aureolatum-related cases. These findings highlight the importance of incorporating vector distribution into surveillance, prevention, and clinical management strategies to better address the distinct epidemiological contexts within the State of São Paulo.
