title: Analysis of the transmission of Trypanosoma cruzi infection through hosts and vectors.
abstract: Calculating epidemiological measures of infection by Trypanosoma cruzi, the causative agent of Chagas disease, is complex, because it involves several species, different stages of infection in humans and multiple transmission routes. Using the next-generation matrix method, we analysed a model which considers the three stages of human infection, triatomines and dogs (the main domestic reservoirs of T. cruzi when triatomines are present) and the main transmission routes. We derived R 0 and type-reproduction numbers T. We deduced formulas for the number of new infections generated through each transmission route by each infected individual. We applied our findings in Argentine Gran Chaco. The expressions achieved allowed quantifying the high infectivity of dogs and emphasizing the epidemiological importance of the long and asymptomatic chronic indeterminate stage in humans in the spread of the infection. According to the model, it is expected that one infected human infects 21 triatomines, that 100 infected triatomines are necessary to infect one human and 34 to infect a dog, and that each dog infects on average one triatomine per day. Our results may allow quantifying the effect of control measures on infected humans, triatomines and dogs (or other highly infected vertebrate) or on a specific route of transmission, in other scenarios.
authors.affiliation: Departamento de Métodos Cuantitativos y Sistemas de Información,Facultad de Agronomía,Universidad de Buenos Aires,Av San Martín 4453,C1417DSE,Buenos Aires,Argentina.
authors.forename: María C
authors.initials: MC
authors.lastname: Fabrizio
authors.affiliation: Departamento de Ecología, Genética y Evolución,Facultad de Ciencias Exactas y Naturales,Universidad de Buenos Aires, Ciudad Universitaria, IEGEBA (CONICET),C1428EHA,Buenos Aires,Argentina.
authors.forename: Nicolás J
authors.initials: NJ
authors.lastname: Schweigmann
authors.affiliation: Departamento de Métodos Cuantitativos y Sistemas de Información,Facultad de Agronomía,Universidad de Buenos Aires,Av San Martín 4453,C1417DSE,Buenos Aires,Argentina.
authors.forename: Norberto J
authors.initials: NJ
authors.lastname: Bartoloni
mesh_terms: D000818:Animals; D001118:Argentina / Q000453:epidemiology; D014355:Chagas Disease / Q000453:epidemiology / Q000635:transmission*; D004197:Disease Reservoirs; D004283:Dog Diseases / Q000453:epidemiology / Q000469:parasitology / Q000635:transmission*; D004285:Dogs; D019353:Endemic Diseases; D006801:Humans; D007303:Insect Vectors / Q000469:parasitology*; D008954:Models, Biological; D008962:Models, Theoretical; D012424:Rural Population; D014225:Triatominae / Q000469:parasitology*; D014349:Trypanosoma cruzi / Q000502:physiology*
keywords: Chagas disease; Trypanosoma cruzi; mathematical model; next-generation matrix