Eco-epidemiological study of arboviruses in non-human primates in the State of São Paulo

Author(s)

Leonardo La Serra

• Document type: Doctoral Thesis
• Press: Ribeirão Preto.
• Institution: Universidade de São Paulo (USP). Faculdade de Medicina de Ribeirão Preto (PCARP/BC)
• Defense date: 2023-06-30

Examining board members

Luiz Tadeu Moraes Figueiredo; Mirela Darc Ferreira da Costa; Rodrigo de Carvalho Santana; Ricardo Luiz Moro de Sousa

• Advisor: Luiz Tadeu Moraes Figueiredo; Gilberto Sabino dos Santos Júnior

Abstract

Viruses transmitted by arthropods (arboviruses) cause epidemics of important human diseases representing serious public health problems in tropical and subtropical countries. Viruses from the families Togaviridae (Mayaro and Chikungunya) and Flaviviridae (Dengue, Zika, yellow fever and SLEV) have been found in recent years in Brazil as emerging or reemerging diseases. Wild animals have been identified to be infected with these arboviruses, including non-human primates (NHP). In this context, the objectives of this thesis were: (i) to detect and identify arboviruses in blood, saliva, feces and urine samples of free range NHP, in captivity or found dead, in the Northeast and Northwest of the State of São Paulo using semi-nested multiplex RT-PCR; (ii) verify active infection of the arboviruses found in biological samples of the animals through viral isolation when possible, (iii) and genomic characterization through nucleotide sequencing, phylogenetic analyzes and molecular epidemiology of the detected viruses; (iv) to evaluate the ecological aspects related to the detection of arboviruses in PNH, detecting risk areas for infection by the studied arboviruses in the Northeast and Northwest regions of the State of São Paulo. We found evidence of a silent co-circulation of several Flavivirus arboviruses of interest to public health in PNH collected in urban areas. Flaviviruses DENV1, DENV2 and DENV3, YFV, ZIKV and SLEV were found to infect PNH in the Northeast and Northwest regions of the state of São Paulo; the unprecedented infection by SLEV was observed in the primate Saguinus midas; SLEV and ZIKV were found in samples of saliva and rectal swabs from HNP, showing a risk for a possible non-vector transmission of the virus, which needs to be proven in future studies; co-infections of SLEV and ZIKV, as well as ZIKV and DENV3 were observed in PNH. It was possible to verify that the city of Ribeirão Preto is a risk zone for arboviruses, particularly in the central region and in the surroundings of Bosque Zoológico. Future studies are needed to verify the presence of maintenance cycles of flaviviruses DENV, SLEV and ZIKV among PNH, vectors and humans. (AU)

• FAPESP's process: 16/25763-5 - An eco-epidemiological study of the Zika Virus in the Northeastern Region of the State of São Paulo
• Grantee: Leonardo La Serra
• Support Opportunities: Scholarships in Brazil - Doctorate