Which achievement is attributed to Pasteur?

Which achievement is attributed to Pasteur?

• A. Observation of phagocytosis
• B. First attenuated vaccines
• C. Discovery of opsonins
• D. Theory of humoral immunity

Answer: (B)

The main idea tested is how vaccines can be made to safely provoke immunity. Pasteur showed that weakening a microbe can still train the immune system without causing illness, leading to the first successful attenuated vaccines. This approach was demonstrated with vaccines against chicken cholera, anthrax, and later rabies, establishing a practical method for protective immunity that underpins many vaccines today. Observations like phagocytosis were work of Metchnikoff, not Pasteur; the idea of opsonins relates to how antibodies enhance phagocytosis (a concept linked to Ehrlich); and the humoral immunity theory was developed by Behring and Kitasato. So the achievement most clearly attributed to Pasteur is the development of the first attenuated vaccines.

The main idea tested is how vaccines can be made to safely provoke immunity. Pasteur showed that weakening a microbe can still train the immune system without causing illness, leading to the first successful attenuated vaccines. This approach was demonstrated with vaccines against chicken cholera, anthrax, and later rabies, establishing a practical method for protective immunity that underpins many vaccines today. Observations like phagocytosis were work of Metchnikoff, not Pasteur; the idea of opsonins relates to how antibodies enhance phagocytosis (a concept linked to Ehrlich); and the humoral immunity theory was developed by Behring and Kitasato. So the achievement most clearly attributed to Pasteur is the development of the first attenuated vaccines.