Chigger mites of Brazilian birds: morphological studies and investigation of the presence of associated pathogens

Author(s)

Ricardo Bassini Silva

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Faculdade de Medicina Veterinária e Zootecnia (FMVZ/SBD)
• Defense date: 2021-03-30

Examining board members

Darci Moraes Barros Battesti; Marcos Rogério André; João Luiz Horácio Faccini; Marcelo Bahia Labruna; Valéria Castilho Onofrio

• Advisor: Darci Moraes Barros Battesti; Fernando de Castro Jacinavicius

Abstract

Brazil has 63 species of chiggers parasitizing different groups of animals. And of these, only 8 species were reported to birds, and one belongs to the genus Apolonia, two from Blankaartia, two from Eutrombicula, one from Neoschoengastia, and two from Parasecia. These mites’ larvae can cause deep and itchy lesions at the bite side, with to intense skin reactions in the host, causing dermatitis popularly known as thrombiculiasis. In several countries, public health departments faced the need for cataloging and knowledge of these mites’ biology as they are considered potential vectors of pathogens. In Brazil, cases of Brazilian Spotted Fever (FMB) diagnosed in São Paulo were associated with these mites because they were found in the disease’s outbreaks. However, its role in the epidemiology of pathogens has not been confirmed. In this study, a type catalog of the UNSM collection was prepared to contain about 1,026 type species. Six species were redescribed, and microscopy images were provided to assist in the description of these species. New locality records and host associations were provided for species B. sinnamaryi, E. alfreddugesi, E. batatas, E. goeldii and E. tinami. Five new species of the genus Eutrombicula have been described. The species E. butatantensis has been re-established as a valid species, and E. ophidica is being synonymized with E. butantanensis. Finally, two different strains of Rickettsia sp. were detected in B. sinnamaryi and E. tinami parasitizing birds in Brazil. (AU)

• FAPESP's process: 17/01416-7 - Chigger mites from Brazilian birds: morphological studies and investigation of the presence of pathogens
• Grantee: Ricardo Bassini Silva
• Support Opportunities: Scholarships in Brazil - Doctorate