Why doctors tried fever against brain syphilis
Syphilis can spread to the nervous system, where it may cause neurosyphilis—damage that can lead to confusion, personality changes, paralysis, and eventually death. Before antibiotics, doctors had few effective ways to treat its most severe form. In the late 19th and early 20th centuries, some began deliberately triggering high fevers, based on the observation that syphilis symptoms sometimes improved after illnesses that caused intense fever.
Turning malaria into a treatment
The physician Julius Wagner-Jauregg developed a method of infecting patients with malaria to provoke repeated bouts of fever. Malaria was chosen because it could produce sustained temperature spikes and, unlike many fever-causing infections, could be treated with medication afterward. Doctors used quinine to suppress the malaria once it had served its intended purpose.
The aim was not to cure malaria with heat. Rather, doctors hoped the fever would weaken the syphilis infection or interrupt its effects on the brain. The precise biological explanation was unclear, and the treatment did not offer a dependable cure. It was a calculated gamble: malaria itself could be life-threatening, and controlling it did not eliminate the danger.
A risky bridge to antibiotics
The approach became known as malariotherapy and was used particularly for patients with general paresis, a devastating brain disorder caused by late-stage syphilis. Wagner-Jauregg received the 1927 Nobel Prize in Physiology or Medicine for his discovery of the therapeutic value of malaria inoculation in treating that condition.
That recognition reflected how desperate the situation had been, not how safe the procedure was. Once penicillin became available, it could treat syphilis without deliberately giving patients another serious infection. Malariotherapy faded, leaving a striking reminder of the tradeoffs doctors faced before antibiotics: sometimes the proposed treatment was to make a patient dangerously ill in the hope of stopping an even more destructive disease.
