A year after Urquiza was assassinated, Argerich treated the victims of Buenos Aires' epidemics of Cholera in 1867 and Yellow Fever in 1871. Argerich was identified as one of the "ministering angels" who was not part of the mass exodus from the city, but stayed behind at his peril to tend to the sick who remained in Buenos Aires. He is depicted treating a patient alongside Dr. Roque Perez in Juan Manuel Blanes' iconic 1871 portrait, "Yellow Fever" of the great Buenos Aires epidemic of 1871.