Malaria Flashcards
What treatment options are available for severe malaria?
7-10 day, IV aremisinin or quinine
IV fluids and supportive therapy
Why isn’t *Plasmodium vivax *in Africa?
Because there is some sort of resistance conferred in the African genome
Why don’t CD8 T cells play a major roll in blood stage immunity?
Because RBCs don’t express MHC
What are some of the clinical syndromes seen in severe malaria?
Cerebral malaria - Coma, convulsions
- long term neurological deficits
Respiratory distress
Metabolic acidosis
What is the major aspect of immunity that develops towards blood stage merozoites?
The antibody response that coat merozoites to prevent them from invading RBCs and growing
Antibodies that opsonise infected RBCs so they can be phagocytosed by macrophages/monocytes/neutrophils
Describe the immunity that develops towards sporozoites
Antibodies coat the sporozoites preventing them from infecting hepatocytes
Describe the immunity that develops towards the liver stage of malaria infection?
CD8 T cells
What are some potential sequelae of mother’s getting malaria during pregnancy?
Low birth weight babies
Stillbirths and miscarriage
Which species of malaria can become dormant in the liver?
P. vivax
What treatment option is available for mild malaria?
A short course treatment with aremisinin combination therapy
What is the life cycle of malaria parasite?
Sporozoites are injected into the blood > Travel to the liver > Incubate for 7-10 days > merozoites burst out of hepatocytes and enter blood > merozoites infect RBCs (disease) > gametocytes are released
What parasite factors makes the development of immunity towards malaria so slow?
Multiple target antigens
Antigenic diversity: major targets show substantial diversity
Antigen variation: gene families allow switching to avoid the immune response
What is the pathophysiology of disease progression in severe malaria?
Parasite is in the blood
- It accumulates in organs
- There is the immune response
- RBCs are killed, both directly by the pathogen and uninfected RBCs by the spleen
What stage of the malaria lifecycle is the immune response primarily directed against?
Blood stage (merozoites)
What genus of mosquito transmits malaria parasite?
Anopheles
