One of the first to refute the idea that maggots spontaneously generate on meat left out in the open air. He predicted that preventing flies from having direct contact with the meat would also prevent the appearance of maggots. 

Robert Koch identified that bacterial pathogen causing anthrax is Bacillus anthracis which he had observed from the blood of a cattle. What lead to this discovery is his experiments from which he gathered data based on his observations. 

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Dr. Alphonse Laveran discovers the cause of Malaria by observing black pigments from freshly drawn blood of patients. 

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Koch cultured bacteria in gelatin after various experiments since he determined the importance of having a solid medium where bacteria will be cultured. 

Koch identified the bacterial pathogen for tuberculosis, Myobacterium tuberculosis.

Carle Gessard became the first one to determine and provide a description of the Pseudomonas aeruginos

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Autoclave was further developed

Christian Gram develops Gram staining. It is a method used to differentiate positive and negative gram bacteria. 

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The cause of diarrhea, Escherichia coli, is discovered by Theodor Escherich. 

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Antitoxins for diphtheria and tetanus developed and prepared by Emil Von Behring.

Winogradsky, from 1887, studies sulfur and nitrifying bacteria, and discovers chemosynthesis.

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In 1892, Waldemar Haffkine develops a cholera vaccine that is deemed effective in preventing increase of cases. 

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Sir Almroth Edward Wright developed the first effective typhoid vaccine and was first utilized on the British military.

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