Dr Oswaldo Cruz is one of the entities channelled by John of God in his healing sessions.

Dr Cruz, called the sanitation doctor, was born on the 5th of August 1872 in Sao Luis do Paraitinga in Sao Paulo, Brazil. His father, Dr Bento Goncalvez Cruz was Brazil's top public health officer under Emperor Dom Pedro II. During Oswaldo’s childood, the family moved to Rio de Janiero. Here at the age of 15 Oswaldo entered the Faculty of Medicine and at 20 graduated as a doctor specialised in water sanitation.

In his mid 20s Dr Cruz went to Paris and did research in bacteriology at the Pasteur Institute. Three years later he returned to Brazil to study and help contain the bubonic plague outbreak in the port of Santos. To facilitate this process an Institute was established and in 1902 Dr Cruz became its Director. Under his guidance the Institute earned a reputation for both research and teaching. In 1908 its name was changed to the Institute of Oswaldo Cruz.

In later years Dr Cruz became the General Director of Public Health. Dr Cruz is widely praised for his pioneering work on identifying and controlling yellow fever, bubonic plague, malaria and smallpox. Of particular importance is his use of vaccines and instituting the modern medical practices of notification, quarantine of cases, eradication of pests carrying the disease and improvement to public hygeine. Although these were not always popular public policies they were central in the eradication of epidemics of these illnesses. Dr Cruz consequently became a national hero.

• For health reasons, Dr Cruz resigned from the Institute in 1915 and moved to the small city of Petropolis where he became mayor and instigated a reforming process of public sanitation and urbanisation. He died of kidney failure in 1917. Dr Cruz is remembered as the father of sanitation and environmental medicine in Brazil.