The prophylactic measures against dissemination of smallpox, such as inoculation and other sanitary precautions, have not always succeeded in controlling the spread of variola in Brazil, and could not prevent penetration of this extraordinarily infectious disease into distant jungle areas. Infection of Indians in the jungles was followed by infection of simian species Mycetes seniculus Kuhl and Cebus capucinus Erxl found relatively often in these distant jungle areas. Cadavers of these monkeys were found under trees from which they had fallen. Diseased and dead animals were covered with numerous variola pustules which due to the furry coat were less visible than in man.
Trans. of Muenchener Medizinische Wochenschrift (Germany) v69 p1009-1010 1922.