DETECTION AND MOLECULAR CHARACTERIZATION OF Neorickettsia spp. IN BATS IN THE STATE OF ACRE

• Grant number: 23/01545-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2023
• End date: April 30, 2024
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Preventive Veterinary Medicine
• Principal Investigator: Marcos Rogério André
• Grantee: Abraão Isaque da Silva
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

Currently, four species of the genus Neorickettsia (Rickettsiales: Anaplasmataceae) are described: Neorickettsia sennetsu, Neorickettsia helminthoeca, Neorickettsia risticii and Neorickettsia findlayensis. Certain species of digenetic flukes can harbor bacteria of the genus Neorickettsia, which are transmitted vertically from one developmental stage of the fluke to the next or horizontally to the definitive vertebrate host. Neorickettsia risticii, the etiological agent of Equine Monocytic Neorickettsiosis (EMN) or Potomac Horse Fever (PHF), in horses in the United States, Canada, Argentina, Uruguay and Brazil, is transmitted by ingestion of operculated freshwater snails containing immature forms of infected trematodes with the said agent. Bats, in addition to harboring N. risticii infected adult flukes, also act as reservoirs for this Anaplasmataceae agent. However, there are few studies that aimed to investigate the occurrence and molecular identity of Neorickettsia spp. in bats or associated trematodes in the world. The present study aims to investigate the occurrence of N. risticii DNA in spleen samples of bats in the State of Acre. For this purpose, 273 bats belonging to 32 different species were captured in two municipalities in the State of Acre: Rio Branco and Xapuri. DNA samples will be extracted from spleen fragments of captured animals. To verify the absence of inhibitors in the DNA samples, a PCR assay based on the endogenous mammalian gapdh gene will be performed. Positive samples in said PCR will be screened for Neorickettsia detection using nested PCR based on the 16S rRNA gene. Positive samples will be subjected to PCR assays based on p51 and groEL genes. The amplicons will be purified and sequenced by the Sanger method. The obtained sequences will be confronted with those previously deposited in Genbank and subsequently submitted to phylogenetic inferences. The results of the present study will contribute to the knowledge about the occurrence and diversity of Neorickettsia spp. in bats in the Brazilian territory. Additionally, the present study will bring important information about the diversity of Neorickettsia genotypes in bats in northern Brazil, as well as contribute to the understanding of the eco-epidemiology of N. risticii among vertebrates in the region.