When was disease discovered?

The concept of disease has existed for thousands of years. The ancient Egyptians, Greeks, and Romans all had well-developed medical systems and theories of disease causation. In the early days, disease was often thought to be caused by supernatural forces, such as demons or evil spirits. As scientific knowledge advanced, it became clear that disease is caused by natural factors, such as microorganisms and genetic defects. The modern concept of disease is constantly evolving as new theories and treatments are developed.