The disease was named after the Brazilian physician and epidemiologist Carlos Chagas , who first described it in 1909 . The disease was not seen as a major public health problem in humans until the 1960s ( the outbreak of Chagas disease in Brazil in the 1920s went widely ignored ) . Dr Chagas discovered that the intestines of Triatomidae ( now Reduviidae : Triatominae ) harbored a flagellate protozoan , a new species of the Trypanosoma genus , and was able to demonstrate experimentally that it could be transmitted to marmoset monkeys that was bitten by the infected bug . Later studies showed squirrel monkeys was also vulnerable to infection .