Such views were held in disdain, however, and Galen's miasma theory remained dominant among scientists and doctors.
The nature of this doctrine prevented them from understanding how diseases actually progressed, with predictable consequences.
These small organisms, too small to see without magnification, invade humans, animals, and other living hosts.
Their growth and reproduction within their hosts can cause a disease.
The earliest physical evidence of it is probably the pustular rash on the mummified body of Pharaoh Ramses V of Egypt. Variola major was the severe and most common form, with a more extensive rash and higher fever.
Variola minor was a less common presentation, and a much less severe disease, with historical death rates of 1 percent or less.
The condition is present at birth (congenital) as a result of missing nerve cells in the muscles of the baby's colon.Bayoud destroyed the world's most renowned varieties that are susceptible to the disease and particularly those which produce high quality and quantity fruit (Medjool, Deglet Nour, Bou Fegouss).It also accelerated the phenomenon of desertifi cation (Figures 90a and b).In addition, a form called variola sine eruptione (smallpox without rash) was seen generally in vaccinated persons.In the study of ancient diseases, nothing speaks like the dead.