Experimental pathogenicity of four opportunist Fusarium species in a murine model.

A murine model with immunocompetent animals was used in a comparative study of experimental pathogenicity of 13 isolates belonging to the four most frequent pathogenic species of Fusarium in man (F. solani, F. oxysporum, F. verticillioides and F. proliferatum). Inocula of 5 x 10(6) conidia/mouse of each isolate of Fusarium were injected into a lateral vein of the tail of the mice to produce a systemic infection. F. solani was the most virulent species; the five strains of this species assayed caused the death of all the animals tested in <19 days. The other species of Fusarium were not virulent in this model. The organs mainly affected by F. solani were the kidneys and the heart. These findings correlate with the clinical evidence and demonstrate that there is a high risk associated with infection by F. solani, especially for immunocompromised patients.