Characterization of Trypanosoma cruzi isolated from humans, vectors, and animal reservoirs following an outbreak of acute human Chagas disease in Santa Catarina State, Brazil.
During March 2005, 24 cases of acute human Chagas disease were detected in Santa Catarina State, southern Brazil, all of them related to the ingestion of Trypanosoma cruzi-contaminated sugar cane juice. Following field studies allowed the isolation of 13 T. cruzi strains from humans, opossums (Didelphis aurita and Didelphis albiventris), and vectors (Triatoma tibiamaculata). The isolated strains were characterized by multilocus enzyme electrophoresis (MLEE) and analysis of the spliced-leader and 24Salpha rRNA genes. The assays revealed that all strains isolated from humans belong to the TcII group but revealed a TcII variant pattern for the phosphoglucomutase enzyme. Strains isolated from opossums also showed a TcI profile in all analysis, but strains isolated from triatomines revealed a mixed TcI/TcII profile by MLEE. No indication of the presence of Trypanosoma rangeli was observed in any assay. Considering that mixed strains (TcI/TcII) were isolated from triatomines in an area without active vectorial transmission to humans and that all strains isolated from humans belong to the TcII group, our results show that T. cruzi TcI and TcII groups are circulating among reservoirs and vectors in southern Brazil and indicate that selection toward TcII group in humans may occur after ingestion of a mixed (TcI/TcII) T. cruzi population.
Steindel
Mário
M
Departamento de Microbiologia e Parasitologia, Universidade Federal de Santa Catarina, Florianópolis, 88040-900, SC, Brazil.
Kramer Pacheco
Letícia
L
Scholl
Daniele
D
Soares
Marcos
M
de Moraes
Milene Hoehr
MH
Eger
Iriane
I
Kosmann
Cecília
C
Sincero
Thais Cristine Marques
TC
Stoco
Patrícia Hermes
PH
Murta
Silvane Maria Fonseca
SM
de Carvalho-Pinto
Carlos José
CJ
Grisard
Edmundo Carlos
EC
D000818:Animals; D001938:Brazil / Q000453:epidemiology; D014355:Chagas Disease / Q000453:epidemiology* / Q000469:parasitology*; D004196:Disease Outbreaks; D004197:Disease Reservoirs / Q000469:parasitology; D004199:Disease Vectors; D004592:Electrophoresis, Starch Gel; D004798:Enzymes / Q000032:analysis; D020459:Genes, rRNA; D006801:Humans; D017720:Molecular Epidemiology; D009893:Opossums / Q000469:parasitology; D015800:Protozoan Proteins / Q000032:analysis; D014224:Triatoma / Q000469:parasitology; D014349:Trypanosoma cruzi / Q000145:classification* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification*
D004798:Enzymes; D015800:Protozoan Proteins