What scientist discovered vaccines?

Answer 1

It is Louis Pasteur. In France in the late 1870s, anthrax was a severe disease that destroyed flocks of sheep. This influenced Louis Pasteur to direct his attention to the study of anthrax. He had just developed a regimen for heat attenuation of the causative agent of chicken cholera, and he used a similar approach in his studies of virulent anthrax bacilli. Cultures of the organism grown at elevated temperatures were shown to be decreased in virulence.

In historic field trials at Pouilly-le-Fort in 1881, Pasteur showed that these heat-attenuated organisms were capable of producing immunity against later challenge with virulent strains of the bacillus in animals. Pasteur is therefore given credit for developing the first vaccine effective in the prevention of anthrax.