Dictionary of Tropical Medicine

Malaria

A protozoan disease of humans caused by blood parasites of the species, Plasmodium falciparum, P. vivax, P. ovale or P. malariae and transmitted by anopheline mosquitoes. P. falciparum is most likely to cause death, if untreated,. and can also be a great mimicker in its presentation. Malaria should be suspected in anyone with a fever or who is otherwise unwell and has returned from a malarious area.

Malaria prophylaxis

Measures taken for protection against malaria, e.g. administration of a drug and personal protective measures that prevent a person from becoming infected with the disease.

Malignant

Ability of cancer to invade local tissue and to spread to distant sites in the body.

Mamba

Highly venomous African elapid snakes. Include the green mamba and the black mamba.

Manubrium

The tube between the stomach and the mouth of a jellyfish - equivalent to the oesophagus in humans.

Marburg Disease

A serious African viral haemorrhagic fever harboured by monkeys. Named after the city of Marburg in Germany where a serious outbreak occurred amongst laboratory workers handling the tissues of African Green (Vervet) monkeys.

Mebendazole

An effective and safe benzamidazole anthelmintic with a wide spectrum of action against intestinal nematodes including hookworms, Ascaris, Enterobius and Trichuris.

Medusa

The adult, recognisable stage of a free-swimming jellyfish.

Mefloquine

An antimalarial related to quinine, tetracycline and halofantrine used to suppress blood parasites, especially chloroquine resistant strains of Plasmodium falciparum. There has been increasing resistance to mefloquine reported in malaria due to Plasmodium falciparum.

Mehlis's glands

A unicellular gland in cestodes, which encircles the ootype. Its function is not known.

Melanoma

Any tumour of melanin-pigmented cells. Usually has highly malignant properties.

Melioidosis

An infectious disease caused by a soil bacterium, Burkholderia pseudomallei, seen in many areas of the tropics and is particularly prevalent during the wet season. The illness may present in a number of ways including life threatening acute septicaemia as well as pneumonia and chronic suppuration, which has a lower mortality

Meningococcus

Neisseria meningitidis.

Merozoites

A stage of the life cycle of the malarial parasite.

Mesoendemic

The disease is found among small, rural communities with varying intensity depending on local circumstances.

Mesogloea

The jelly part of a jellyfish - the thickened substance between the epidermis and gastrodermis that gives the jellyfish its shape.

Metaplasia

Change of a mature type of cell in a tissue to another mature type of cell usually present in another tissue; e.g., development of squamous epithelium in the trachea among the normal respiratory epithelium = squamous metaplasia.

Metastasis

The spread of cancer cells through the blood, lymphatics or directly and establishment of these new groups of cells at locations distant from the original cancer.

Metazoa

That division of the animal kingdom which embraces all animals whose cells become differentiated to form tissues. It includes all animals except the protozoa.

Metronidazole

An antibiotic used widely for anaerobic bacterial infections (including pseudomembranous colitis) and also for such protozoan infections as giardiasis, trichmoniasis and amoebiasis.

Micrometer

A unit of measurement. 1 um = 1 thousandth of a mm.

Mixed tumour

A neoplasm with a number of different cell types undergoing cancerous change.

Mollusc

Invertebrates such as snails which mostly have a shell. Includes the octopus.

Molluscicide

A substance (or chemical) which kills molluscs, such as snails.

Monkey B virus

A herpes virus of monkeys that can infect humans, usually through handling monkey tissues at autopsy or in the laboratory.

Monkey pox

A pox viral disease of monkeys in Central Africa which can infect humans.

Morbakka

The colloquial name for a number of large box-jellyfish with a single tentacle in each corner. There are probably a number of species that are grouped under this name. The sting causes a burning pain to the skin and rarely, a mild Irukandji syndrome. See also: Moreton Bay carybdeid, and Fire jelly.

Morbidity

Something that affects the normal body functioning, but not causing death. The condition of being diseased or morbid or sick.

Moreton Bay carybdeid

A morbakka that is often caught in the Moreton Bay area, just north of Brisbane, Queensland. See also Fire jelly.

Morphology

The type of form or structure of a plant or animal.

Mortality

The effects of something resulting in death. The quality of being mortal or dead. The death rate; the ratio of total number of deaths to the total population.

Mortality rate

The percentage that die within a specified period of time.

Mosquito repellent

Any substance producing a negative response in mosquitoes, causing them to avoid a close approach (such as alighting on the skin of a host animal or entering a treated room). (See also DEET).

Multilocular hydatid

Larval stage of Echinococcus multilocularis in which exogenous development occurs resulting in infiltration of tissues.

Murine typhus

A zoonotic febrile disease caused by the rodent bacterial species, Rickettsia typhi, and transmitted by fleas of the genus Xenopsylla.

Muscle pump

The contraction and relaxation of the limb muscles that helps pump the low pressure venous blood from the extremities back to the central collecting system.

Myiasis

Infection of mammals (including humans) by certain dipterous larvae (maggots). Various clinical forms recognised, including cutaneous myiasis, intestinal myiasis, ophthalmomyiasis, urinogenital myiasis and sanguinivorous myiasis.