Pasteur produced the first vaccine for rabies by growing the virus in rabbits.

Pasteur injected ‘clean’ animals with the rabies germ found in spinal cord that was fourteen days old. At this age, the germ was relatively weak and unlikely to threaten the life of the animals. He then used spinal cords that were thirteen days old, twelve days etc. on the animals until they were injected with the most virulent germ found in infected spinal cord that was fresh. All survived this. But Pasteur faced a serious problem. What worked on animals might not work on humans.

In 1885, a young boy, Joseph Meister, had been bitten by a rabid dog, and was brought to Pasteur. The boy almost certainly would have died an agonising death if nothing was done so Pasteur took the risk on using his untested vaccine.

The boy survived and Pasteur knew that he had found a vaccine for rabies. Three months later, when he examined Meister again, Pasteur reported that the boy was in good health.

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