IMMUNOLOGY

Detailed explanation-1: -The germ theory of disease states that many diseases are caused by microorganisms such as bacteria, viruses, protozoa, or fungi. These diseases are caused by the growth and replication of microorganisms. The germ theory of disease was devised by Louis Pasteur.

Detailed explanation-2: -It states that microorganisms known as pathogens or “germs” can lead to disease. These small organisms, too small to be seen without magnification, invade humans, other animals, and other living hosts. Their growth and reproduction within their hosts can cause disease.

Detailed explanation-3: -Still, it has been little more than a century and a half since Robert Koch made the discoveries that led Louis Pasteur to describe how small organisms called germs could invade the body and cause disease.

Detailed explanation-4: -Germ theory reduced the spread of disease to the transmission of these bacteria. Hence, the causes of diseases were conceptualized as local biological impingements. A key move was Koch’s isolation and culturing of the tuberculosis virus, and his demonstration that tuberculosis could be artificially induced in animals.

Detailed explanation-5: -The theory of biogenesis lead the way for the germ theory of disease by refuting the theory of spontaneous generation through experiments demonstrating that microorganisms are the cause of diseases. This helped to establish the germ theory of disease; that life must come from other life.