He has practiced Guerreiro - Machado reaction in 1010 specimens from the same number of people , following the technique of 50% hemolysis of antigen using Bozicevich and total aqueous extract of T. cruzi ( forms of culture in medium Senekjie ) prepared Peruvian strains isolated from people and Trialoma infestans. In the study group , 551 Lima residents who had long previous residence in another department and 459 residents Samegua and Moquegua, locations known for their high endemicity for Chagas included . Reactions in 1010 , he found , 98 ( 9.70 %) were positive , 20 ( 1.98 %) suspicious and 31 ( 3.07 %) anticomplementary . The incidence was higher in females , 12.33 '% , and in the following age groups: 60 and older, 24.42 % ; 50 to 59 years , 13.86 % ; 40 to 49, 13.64 '% and 30 to 39, 9.16 % positive cases . De Lima 551 residents , 34 ( 6.17 % ) presented positive serology ; 1 ( 0.18...