Since humans have tried to cope with disease, they have searched for a relationship within the suffered symptoms and tried to group them into concrete namings in order to better identify them. Until today, this process hasn’t changed, but after the study of pathogenic microorganisms and an within an evolutionary frame, we begin to realize that some symptoms are not only produced by the infecting pathogens, but rather by our organisms as defense mechanisms.

We are beginning to understand that several processes which occur during infection are associated with the strategies for surviving by the microorganisms in order to cope with the aggressive medium which constitutes our body.

Most infectious diseases do not affect bone tissue in a visible form. Therefore in paleopathology, which has only bone remainsavailable, with the exception of mummy studies, renders the establishment of a differential diagnosis extremely difficult. From current clinical data we can estimate that the relatively few chronic infectious diseases, which can affect the skeleton, account for only between 5% and 20% of the patients, which suffered the disease.