Published: July 2007
Did You Know?
In Did You Know? the National Geographic magazine team shares extra information we gathered to expand your knowledge of our featured subjects.
Malaria produces such a predictable fever that there was a time in the early 1900s when people were given malaria on purpose—to stop syphilis, which is caused by an extremely temperature-sensitive bacteria. There were so-called malaria treatment centers throughout Europe and the U.S. Tens of thousands of patients were dosed with malaria parasites, in a controlled setting. It was the best way known to heat a body. The fever came on, the syphilis was halted, and then you cured the patient's malaria—at the time, with quinine. Voilà! The 1927 Nobel Prize was awarded to Austrian physician Julius Wagner von Jauregg for this discovery.

—Michael Finkel