Chapter 7 : The Kinetoplastid Infections: Human African Trypanosomiasis (Sleeping Sickness), Chagas’ Disease, and the Leishmaniases

Abstract:

The kinetoplastid infections constitute a group of three major human protozoan infections caused by single-celled parasites with a flagellum and an unusual DNA-containing cell organelle known as the kinetoplastid. Together, the three major kinetoplastid infections of humans, human African trypanosomiasis (HAT), Chagas’ disease, and leishmaniasis, kill an approximately 150,000 people annually, making them among the most lethal neglected tropical diseases (NTDs). West African HAT typically occurs around rivers, especially in areas of dense vegetation where tsetses of the Glossina palpalis group are abundant. The chapter shows how the fact that Rhodesian HAT is primarily a zoonosis, i.e., a disease transmitted from animals to humans, has important implications for controlling epidemics of this disease. In addition to melarsoprol, there are two other drugs, pentamidine and suramin, still in widespread use for the earlier stage of HAT. The treatment of the chronic complications of Chagas’ disease requires complex modalities. There are no simple preventive chemotherapy approaches for the control of Chagas’ disease, nor is it practical to apply wide-scale case detection and management with antitrypanosomal drugs such as what occurred with the pentamidization campaigns against HAT launched in the 20th century. Approximately 12 million people are infected with Leishmania parasites. There are two major forms of the disease—visceral leishmaniasis, and cutaneous leishmaniasis (CL). Both CL and VL are treatable infections, but many of the drugs used produce severe toxicities, and in many cases they are not available.