Admiral Byrd carried The Merck Manual as he flew over the South Pole, and Dr. Schweitzer took it along to Africa. The Merck Manual is the most widely used medical reference in the world, with a total of 10 million copies sold in 16 languages. The grant will fill a critical void in research funding for the two tropical diseases, Tidwell said. African sleeping sickness, which is fatal unless treated, spreads among people bitten by the tsetse fly. Once bitten by an infected fly, the parasites multiply in the blood and lymph nodes, and then invade the central nervous system, although it may take two years for the gambiense version to show symptoms of central nervous system infection.
Symptoms begin with a low-grade fever, pain in the joints and itchy skin.
Eventually, the parasites carrying the disease enter the brain. Then hallucinations and unpredictable, disruptive behavior are common. A victim experiences excruciating pain. Those infected with gambiense develop drowsiness during the day, but insomnia at night. As the disease progresses, sleep becomes uncontrollable until the patient eventually lapses into a coma before dying.