He was known to the public for his service during cholera outbreak and in establishing hospitals, particularly the Institute for Experimental Hygiene (Istituto di Igiene Sperimentale) in Rome.

He went to France and Germany to have further training in pathology and worked with Rudolf Virchow at the University of Berlin.

He volunteered as army physician, and was posted as lieutenant doctor among the troop called Hunters of the Apennines under the command of Giuseppe Garibaldi.

In 1866 he was designated by the Italian government to control an outbreak of cholera in Palermo, where the disease was rampant among the soldiers.

In 1870 he was offered a post at the newly established Physiological and Pathological Institute of the University of Rome.

Tommasi-Crudeli married Bianca Fortini (who died at the time of Palermo cholera outbreak), but they had no children.

Tommasi-Crudeli was decorated with Silver Medal of Military Valour for his service in the Italian Army.

[3] Tommasi-Crudeli, along with German pathologist Edwin Klebs, made several discoveries that bacteria caused diseases such as typhoid and diphtheria.

They further claimed that through experimental injection in rabbits, the bacterium produced symptoms of malaria such as enlargement of spleen and fever.

But an American physician George Miller Sternberg proved that the bacillus did not cause specific symptoms of malaria in 1881.