The Path Between the Seas

by David McCullough

In 1880, the very year de Lesseps launched his Compagnie Universelle, a French doctor on the staff of a military hospital in Algeria, Dr. Alphonse Laveran, discovered the presence of tiny crescent-shaped bodies wriggling in a blood sample taken from a malaria patient. Incalculably minute, they were detectable only under the strongest microscope, but he had little doubt that they were living organisms and it dawned on him that here was the cause of malaria. He described his discoveries in a letter to the Académie de Médecine in Paris and published a small monograph. Laveran’s claims were not accepted, however, any more than were the theories of Nott or King. The miasma theory had been fixed in people’s minds for generations. In addition, there now appeared a rival claim that seemed to support the miasma theory with scientific fact. Two doctors working in Rome, a German named Klebs and an Italian, Tommasi-Crudeli, had isolated a bacteria from the soil of a malarious region that when injected into a rabbit produced a malaria-like fever. The phenomenal discoveries of Pasteur and Koch had educated everyone to the role of bacteria, that whole other world beneath the microscope, and so it was widely accepted that a bacterium—bacillus malariae—was the long-sought cause of malaria.