Rudolf Weigl - Method of Vaccine Production

Method of Vaccine Production

In 1930, following the 1909 discovery of Charles Nicolle that lice were the vector of epidemic typhus and on the work for the vaccine for the closely related Rocky Mountain Spotted Fever, Weigl took the next step and developed a technique to produce the vaccine by growing infected lice and crushing them into a vaccine paste. He refined this technique over the years until 1933 when he performed large-scale testing. The method specifically broke into 4 major steps:

• Growing healthy lice, for about 12 days
• Injecting them with typhus
• Growing them more, for 5 more days
• Extracting the midguts and grinding them up into a paste (which was the vaccine)

Growing lice meant feeding them blood, the more human the better. At first he tested his method on Guinea pigs but around 1933 he commenced large-scale testing on humans, feeding the lice on human blood by letting them suck on human legs through a screen. This could cause typhus during the latter phase, when the lice were infected. He alleviated this problem by vaccinating the human "injectors" heavily, which successfully protected them from death (though some did develop the disease). Dr. Weigl himself developed the disease, but recovered.

The first major application of this vaccine took place between 1936 and 1943 by the Belgian missionaries in China. The vaccine was dangerous to produce and was hard to make on a large scale. Other vaccines were developed over time that were less dangerous and more economical to produce, including the Cox vaccine developed from egg yolk.