Rickettsia infection in five areas of the state of São Paulo, Brazil

• Published in: Memórias do Instituto Oswaldo Cruz Vol. 102; no. 7; pp. 793 - 801
• Main Authors: Horta, Maurício C, Labruna, Marcelo B, Pinter, Adriano, Linardi, Pedro M, Schumaker, Teresinha T S
• Format: Journal Article
• Language: English
• Published: Brazil Instituto Oswaldo Cruz, Ministério da Saúde 01-11-2007; Fundação Oswaldo Cruz (FIOCRUZ)
• Subjects: Amblyomma; Amblyomma cajennense; Animals; Antibodies, Bacterial; Brazil - epidemiology; Cats - microbiology; Ctenocephalides felis felis; DNA, Bacterial - analysis; Dogs - microbiology; domestic animals; Endemic Diseases; Felis; fleas; Fluorescent Antibody Technique, Indirect; Horses - microbiology; Humans; Ixodidae; opossum; Opossums - microbiology; PARASITOLOGY; Rhipicephalus sanguineus; Rhopalopsyllus; Rickettsia; Rickettsia - genetics; Rickettsia - immunology; Rickettsia - isolation & purification; Rickettsia felis; Rickettsia Infections - epidemiology; Rickettsia Infections - microbiology; Rickettsia Infections - veterinary; Siphonaptera - microbiology; spotted fever; ticks; Ticks - microbiology; TROPICAL MEDICINE; Brazil; spotted fever; domestic animals; opossum; Rickettsia; ticks; fleas
• ISSN: 0074-0276; 1678-8060; 0074-0276; 1678-8060
• DOI: 10.1590/S0074-02762007000700003

This study investigated rickettsial infection in animals, humans, ticks, and fleas collected in five areas of the state of São Paulo. Eight flea species (Adoratopsylla antiquorum antiquorum, Ctenocephalides felis felis, Polygenis atopus, Polygenis rimatus, Polygenis roberti roberti, Polygenis tripus, Rhopalopsyllus lugubris, and Rhopalopsyllus lutzi lutzi), and five tick species (Amblyomma aureolatum, Amblyomma cajennense, Amblyomma dubitatum, Ixodes loricatus, and Rhipicephalus sanguineus) were collected from dogs, cats, and opossums. Rickettsia felis was the only rickettsia found infecting fleas, whereas Rickettsia bellii was the only agent infecting ticks, but no animal or human blood was shown to contain rickettsial DNA. Testing animal and human sera by indirect immunofluorescence assay against four rickettsia antigens (R. rickettsii, R. parkeri, R. felis, and R. bellii), some opossum, dog, horse, and human sera reacted to R. rickettsii with titers at least four-fold higher than to the other three rickettsial antigens. These sera were considered to have a predominant antibody response to R. rickettsii. Using the same criteria, opossum, dog, and horse sera showed predominant antibody response to R. parkeri or a very closely related genotype. Our serological results suggest that both R. rickettsii and R. parkeri infected animals and/or humans in the studied areas.