tropical medicine, medical science applied to diseases that occur primarily in countries with tropical or subtropical climates. Tropical medicine is a critical part of global health, particularly because it encompasses preventable diseases that affect impoverished communities and regions. Among afflictions that fall within the field of tropical medicine are major infectious diseases, such as HIV/AIDS and tuberculosis; neglected tropical diseases, such as Chagas disease, onchocerciasis (river blindness), and schistosomiasis; and some noninfectious conditions, such as malnutrition.
Tropical medicine began to emerge in the 19th century, when physicians charged with the medical care of colonists and soldiers first encountered infectious diseases unknown in the temperate European climate. Several major advances in the control of tropical diseases occurred in the last quarter of the 19th century. For example, Scottish physician Sir Patrick Manson showed that the parasite that caused filariasis was transmitted by mosquito bites. Other tropical diseases were also soon shown to be spread by mosquitoes, including malaria in 1898 and yellow fever in 1900. Within a few years the role of the tsetse fly in transmitting sleeping sickness, the sand fly in kala-azar, the rat flea in plague, the human louse in epidemic typhus, and the snail in schistosomiasis were also discovered. Most early efforts to control tropical diseases involved measures such as the rigorous draining of swamps and other mosquito-breeding areas. These and other environmental measures continue to be among the most effective available, although the introduction of new therapeutic agents, especially new antibiotics and antiparasitic drugs, has also had an impact on some common tropical diseases.
The destructive social and economic effects of tropical diseases soon caused the research emphasis to shift from clinical practitioners in the tropics to organized research institutes in Britain and other colonizing countries. National and international commissions were organized by the colonial powers to eradicate plague, malaria, cholera, yellow fever, and other common tropical conditions, at least from areas in which Europeans lived and worked. The first schools devoted to the study of tropical medicine were founded in England in 1899, and many others soon followed.
In the mid-20th century many colonies achieved independence, and the resulting new countries’ governments took over most research and prevention efforts. Many countries worked closely with the World Health Organization to develop coordinated disease prevention, elimination, and eradication efforts.