title: Outcome of oral infection in mice inoculated with Trypanosoma cruzi IV of the Western Brazilian Amazon.
abstract: A new epidemiological view of American trypanosomiasis or Chagas disease has been formulated in recent decades. Oral transmission of the etiological agent of Chagas disease, Trypanosoma cruzi, has been the most common form of transmission. The T. cruzi discrete typing units TcI and TcIV have been involved in tens outbreaks of acute cases of Chagas disease in the Brazilian Amazon region. We investigated the intensity of infection in mice that were orally inoculated (OR group) with four strains of TcIV that were isolated from two outbreaks of acute Chagas disease that was orally acquired in the state of Amazonas, Brazil. We compared the OR group with mice that were intraperitoneally inoculated (IP group). Blood samples were analyzed by fresh blood examination, hemoculture, and conventional and qualitative real-time polymerase chain reaction (PCR). Samples of different tissues were analyzed by quantitative real-time PCR. The OR group exhibited a higher maximum peak of parasitemia, greater rates of positivity, and higher parasite loads in different tissues during acute infection compared with the IP group, indicating a greater intensity of orally acquired infection. Mice that were orally inoculated with TcIV strains that were obtained from two outbreaks of orally acquired Chagas disease in Amazonas, Brazil, exhibited a more intense course of infection compared with intraperitoneally inoculated mice, reflected by higher levels of parasitemia and parasite loads.
authors.affiliation: State University of Maringá, Avenida Colombo, 5790, Jardim Universitário, 87 020-900, Maringá, Paraná, Brazil. Electronic address: anapeteston@hotmail.com.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Margioto Teston
authors.affiliation: State University of Maringá, Avenida Colombo, 5790, Jardim Universitário, 87 020-900, Maringá, Paraná, Brazil. Electronic address: ana.paula.abreu@hotmail.com.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: de Abreu
authors.affiliation: State University of Maringá, Avenida Colombo, 5790, Jardim Universitário, 87 020-900, Maringá, Paraná, Brazil. Electronic address: c.piva@hotmail.com.
authors.forename: Camila Piva
authors.initials: CP
authors.lastname: Abegg
authors.affiliation: State University of Maringá, Avenida Colombo, 5790, Jardim Universitário, 87 020-900, Maringá, Paraná, Brazil. Electronic address: mlgomes@uem.br.
authors.forename: Mônica Lúcia
authors.initials: ML
authors.lastname: Gomes
authors.affiliation: State University of Maringá, Avenida Colombo, 5790, Jardim Universitário, 87 020-900, Maringá, Paraná, Brazil. Electronic address: mjotoledo@uem.br.
authors.forename: Max Jean
authors.initials: MJ
authors.lastname: de Ornelas Toledo
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001938:Brazil / Q000453:epidemiology; D014355:Chagas Disease / Q000469:parasitology* / Q000635:transmission*; D003141:Communicable Diseases / Q000453:epidemiology; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D007274:Injections, Intraperitoneal; D051379:Mice; D059208:Parasite Load; D018512:Parasitemia / Q000469:parasitology*; D060888:Real-Time Polymerase Chain Reaction; D014349:Trypanosoma cruzi / Q000302:isolation & purification* / Q000472:pathogenicity
keywords: DTU TcIV; Intraperitoneal infection; Mice; Oral infection; Parasite load; Trypanosoma cruzi