Some terms used in parasitology


Acaricide: chemical substance having a cidal or lethal effect on the Acarida, a subclass of the athropods to which ticks and mites belong.

Adjuvant: an additive to a vaccine in order to stimulate or potentiate the immune response. In experimental animals Freund's adjuvant is often used. In humans this is not allowedand as adjuvant BCG is often used

Anaemia: reduced number of erythrocytes or red blood cells often resulting by haemolysis due to the damaging action of intra erythrocytic parasites suchg as Plasmodium or Babesia or by immunological reactions due to the presence of trypanosomes in the circulation.

BCG: Bacille Calmette Guerin of Mycobacterium bovis. The glycoproteins of the cellwall of this bacterium are a powerful adjuvant used as a constituent of a vaccine in combination with vaccinating molecules or cell preparations to stimulate the immune response.

Congenital transmission: transfer of pathogens from mother to foetus via the placenta. In this case the child will be born infected.

Ectoparsites: parasites such as lice and flies that live on the bodies outer surface.

Endoparasites: parasites the infect the internals parts of the body, such as trypanosomes or Ascaris worms.

Facultative parasite: is an organisms that may survive and dwell in the absence of a host but that occasinally infects a host organism.

Haemolysis: lysis of red blood cells due to the damaging action of intra erythrocytic parasites suchg as Plasmodium or Babesia or by immunological reactions due to the presence of trypanosomes in the circulation.

Haematophagous: bloodsucking, used for insects that need blood either as the major nutrient, or for producing fertilized eggs (female mosquitoes or sand flies).

Host: an organism that gives food and shelter to an other organism (often a parasite).

Infestation: contamination with parasites present on the outside of the host organisms, such as by ectoparasites or the contamination of a habitat with mosquitos.

Infection: contamination with parasites present inside of the host organism, such as by malaria parsites or by schistosomes.

Parasite: a organism that lives at the expense of its host.

Quartan fever: fever caused by malaria parasites with a periodicity of 72 hours

Relapses: spontaneous return of the parasitaemia and the disease symptoms after a period of apparent cure.

Sylvatic: from the forest or present in the forest

Tertian fever: fever caused by malaria parasites with a periodicity of 48 hours

thrombocytopenia: condition where there is an abnormally small number of thrombocytes or blood platelets in the circulating blood.

Therapeutic window: difference between the ED50 (half-maximal effective dose) and LD50 (half-maximal toxic dose), indicating the dose range in which the drug is active.

Vector: an agent and very often a biting insect that is responsible for the transmission of the disease.

Zoonosis: a parasitic disease mainly infecting animals and occasionally humans. The animal host serves as the major parasite reservoir.

 

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Last updated: 1 January, 1999.

created by :Fred Opperdoes