8 - Malaria Flashcards
(23 cards)
Where is malaria currently prevalent?
Africa (predominantly central), south america and south east Asia
Where do most deaths from malaria occur
Africa
How many people are at high risk of malaria?
> 1 billion
Name the five species of plasmodium that infects humans
Plasmodium falciparum, plasmodium vivax, plasmodium malariae, plasmodium ovale and plasmodium knowlesi
What is Quotidian Malaria and which species causes it?
A daily fever (fever every 24 hours) caused by plasmodium knowlesi
What is tertian malaria and which species cause it?
A fever every 48 hours caused by either falciparum, vivax or ovale
What is quartan malaria and what species causes it?
Malaria with a fever every 72 hours caused by plasmodium malariae
What is the main way that malaria is transmitted?
By the bite of a female anopheles mosquito
Describe 5 other ways that malaria can be transmitted?
- Introduced malaria - local mosquitoes bite people who acquired malaria abroad and then transmit to local residents
- Airport malaria - infected mosquitoes are transported via aircraft from an endemic country to a non-endemic country
- transfusion malaria - malaria acquired via blood transfusion
- mainline malaria - acquired via sharing needles and syringes
- congenital malaria - infected mothers transmit the pathogen to their child during pregnancy or during delivery
What is a sporozite and what is it’s role in a malaria infection?
A motile spore that is injected into the skin by the mosquito. It then penetrates the blood vessel and enters circulation before it penetrates a hetaptocyte and divides to form merozites
What is a schizont?
A structure formed by the a sexual reproduction of a sporozoite that bursts to release meroziotes
What is a merozoite?
The form of plasmodium that infects red blood cells
What is a trophozoite?
The form of plasmodium that is a single called uncleared mass of protoplasm that modifies the red blood cells in order to require nutrients
What is a gametocyte in relation to malaria?
The sexually developed form of a trophocyte
What is a zygote in relation to malaria?
A diploid form of plasmodium that is formed by the fusing of a micro-male gamete and a female gamete
What is an ookinete in relation to malaria?
A motile form on plasmodium that develops from the zygote that is able to penetrate the intestinal wall of a mosquito
What is an oocyst in relation to malaria?
A differentiated form of a ookinete that grow and internally divide to form sporozoites
Describe 5 factors that lead to the pathogenesis of malaria?
- toxins released when schizonts burst stimulate T cells to produce cytokines which cause fever, bone marrow depression and phagocytosis of RBCs
- anaemia as a result of parasitic growth, reduced erythropoiesis and erythrophagocytosis
- hypoglycaemia
- clotting defects
- immunodepression (increases susceptibility to sepsis)
Give 8 clinical feature/ complications of malaria
- periodic fever
- anaemia
- acute respiratory distress
- hypoglycaemia
- enlargement of the liver and spleen
- haemoglobinuria (Hb in urine)
- haemoglobinaemia (Hb in blood plasma)
- capillary blockages
How is malaria diagnosed?
Blood smears stained with giemsa
What is the main treatment for malaria?
Quinine/chloroquine
How does chloroquine work?
It interferes with haemozoin formation
How is malaria prevented?
Insecticide treated bed nets
