Detection and characterization of bacterial pathogens in chigger mites (Trombiculidae and Leeuwenhoekiidae) using a metagenomic approach

• Grant number: 25/02786-9
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: April 30, 2025
• End date: October 29, 2025
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Preventive Veterinary Medicine
• Principal Investigator: Fernando de Castro Jacinavicius
• Grantee: Isabella Pereira Pesenato
• Supervisor: Maria Carolina Silva de La Fuente
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Institution abroad: Universidad Católica Del Maule, Chile
• Associated to the scholarship: 22/11576-0 - Investigation of Rickettsia spp., Orientia spp. and Borrelia spp. in chigger mites (Trombiculidae and Leeuwenhokiidae) from Brazil, BP.PD

Abstract

Chigger is the popular name for the larval stage of mites from the Trombiculidae s. l. family, which parasitize vertebrates and can cause a cutaneous reaction in the host, known as trombiculiasis. In the Asia-Pacific region, some species of this family are vectors of Tsutsugamushi, a human rickettsiosis caused by the bacterium Orientia tsutsugamushi, which was believed to be restricted to this region of the world, but a few years ago a new species was detected circulating in South America, in Chile, causing disease in humans and being detected in endemic chigger species of the region. Since then, new diagnostic techniques have been developed and adapted to detect bacterial species in chigger mites and in the Americas this work has been mostly conducted by Brazilian and Chilean researchers. Samples will be submitted to molecular and metagenomic assays to determine the presence of microorganisms. Considering the lack of research in this area and the unknown extent of disease transmitted by this arthropod in the Neotropical Region, it is important to analyze factors such as vector, pathogen and host to determine the impact of the human and animal parasitism by this mite group.