Mmic Tutorials1-4 : A Simulated Case

A 85-year-old-male was found to be staying alone in one-flat. It is found that his mattress was soiled with human excreta and urine. The premise is infested with cockroaches, fleas and rats. It is known to the neighbours that the elderly man has the habit of feeding stray dogs and cats in the neighbourhood.

The elderly man was referred to a nursing home and presented with high fever, rash and general weakness.

How would you approach this situation in order to provide final diagnosis of the suspected microorganism[s]?