Malaria (DoD)

Genus of Malaria

Plasmodium

Obligate Human Pathogen

Have to infect humans to maintain their infectious cycle

What do mosquitoes transport?

Sporozoites (Malaria)

Life Cycle of Malaria 

Mosquitoes transfer sporozoite (malaria) → sporozoite travel to liver and change into Schizont → Schizont reproduces asexually and changes into Merozoite (form of malaria parasite that infects RBC) → Leads to Schizont Formation → Schizonts rupture releasing more Merozoites 

Merozoite

Form of malaria that infects the Red Blood Cells

Step 1 of Malaria Lifecyle

Mosquitoes transfer sporozoite (malaria)

Step 2 of Malaria Lifecycle

Sporozoite travel to liver and change into Schizont 

Step 3 of Malaria Lifecycle

Schizont reproduces asexually and changes into Merozoite (form of malaria parasite that infects RBC)

Step 4 of Malaria Lifecycle

Leads to Schizont Formation → Schizonts rupture releasing more Merozoites 

Gametocytes

Male and Female Gametes

Where does sexual reproduction for the malaria parasite occur?

Gut of Mosquito

At what lifestage is the Malaria parasite motile? 

When it becomes a Zygote

Oocysts can rupture and release

Sporozoites (which are then transferred from a mosquito to a new human host)

Vectors of Malaria

Female Mosquitoes

What proportion of the world’s population is at risk for malaria?

Nearly half of the world’s population is at risk for infection (mainly in Africa)

Most Vulnerable for Malaria

Young children, pregnant women, travellers/migrants from nonendemic areas

How does Malaria cause disease and death?

Infects/replicates/kills RBCs (can also release Hemozoin Pigment that stimulates macrophages to produce an inflammatory response)

How does Sickle Cell promote resistance to Malaria infection?

Individuals who are heterozygous (1 good copy and 1 bad copy of the gene) for sickle cell have partial protection of Malaria because the sickle cells don’t support the growth for malaria 

Signs and Symptoms of Malaria

Incubation period of 7-30 days, has cold/hot/sweating stage in uncomplicated malaria (possible relapses)

Diagnosis of Malaria

Peripheral Blood Smear (simplest way and inexpensive), serology (looking for antibodies for plasmodium) and pcr (looking or plasmodium DNA)

Treatment of Malaria

Chloroquine (binds to heme to preventing degradation by plasmodium parasites) but causes bad side effects