This document summarizes the contributions of several scientists who were pioneers in microbiology: - Antonie van Leeuwenhoek was the first to observe microbes under a microscope and determine their small size. - Louis Pasteur established the germ theory of disease and developed pasteurization and microbial fermentation. - Edward Jenner pioneered the concept of vaccines by creating the smallpox vaccine, the first vaccine ever. - Robert Koch identified the specific causative agents of tuberculosis, cholera, and anthrax and developed Koch's postulates to link diseases to microorganisms. - Ignaz Semmelweis demonstrated that hand washing reduced mortality, establishing the importance of hygiene in

1. Scientists

2. Antonie van Leeuwenhoek

3. " (24 October 1632 – 26 August 1723)
One of the first microscopists and microbiologists.
Dutch businessman and scientist in the Golden Age of Dutch science and technology.
Using single-lensed microscopes of his own design, van Leeuwenhoek was the first to experiment with microbes, which he
originally referred toas dierkens, diertgens or diertjes (Dutch for "small animals" [translated into English as animalcules, from
Latin animalculum = "tiny animal"])
He was the first to relatively determine their size.
He was also the first to document microscopic observations of muscle fibers, bacteria, spermatozoa, red blood
cells, crystals in gouty tophi, and blood flow in capillaries.

4. Louis pasteur

5. “Father of microbiology".( December 27, 1822 – September 28, 1895)
French biologist, microbiologist, and chemist
Discovered principles of vaccination, microbial fermentation,
and pasteurization
Germ theory of disease and its application

6. EDWARD JENNER

7. " Father of immunology",(17 May 1749 – 26 January 1823)
English physician and scientist
Pioneered the concept of vaccines including creating the smallpox
vaccine, the world's first vaccine.
Rabies vaccine and Anthrax vaccine

8. ROBERT KOCH

9. Main founders of modern bacteriology,(11 December 1843 – 27 May 1910)
German physician and microbiologist.
Identified the specific causative agents of tuberculosis, cholera, and anthrax
Koch's postulates, a series of four generalized principles linking specific microorganisms to specific diseases
1.The organism must always be present, in every case of the disease.
2.The organism must be isolated from a host containing the disease and grown in pure culture.
3.Samples of the organism taken from pure culture must cause the same disease when inoculated into a
healthy, susceptible animal in the laboratory.
4.The organism must be isolated from the inoculated animal and must be identified as the same original
organism first isolated from the originally diseased host.

10. Ignaz Semmelweis

11. 1818–1865 Ignaz Semmelweis
Hungarian
Concept of hand washing
Demonstrated that doctors washing their hands with chlorine solution
significantly reduced mortality of women giving birth in the hospital
setting.

12. Joseph lister
(5 April 1827 – 10 February 1912),

13. “Father of modern surgery".
British surgeon and a pioneer of antiseptic surgery
Carbolic acid