• Plasmodium falciparum ( 75% )

• P. Malariae, P. ovale, P. vivax ( 25% )

* Appearance changes depends on life cycle stages.

* Plasmodium is most motile during initial infective stages.

Organism that carries a disease from one person to another/ from an animal to human

Insect vector : Female Anopheles mosquitoes

*Only female take blood meals to supply eggs with nutrients

*Also through blood transfusions, use of unsterile needle, and can pass across placenta from mother.

Life cycle of Plasmodium :

1) Plasmodium's gametes fuse, multiplies in and form infective stages in mosquitoes.

2) When mosquito takes a blood meal, parasite enters host with mosquito's anticoagulant and saliva.

3) Infective stages of parasite enter bloodstream and then liver cells.

4) Parasite matures in liver cells, then leaves liver to enter RBCs .

5) Parasites multiply in RBCs, causing RBCs to lyse.

6) Parasites are released and infect other RBCs.

7) Parasites picked up by another mosquito in a blood meal.

2) Reduce number of mosquitoes

• spry insecticides, spread oil over water surface to prevent mosquito breeding, breed fish than feeds in larva, spray Bacillus thuringiensis bacteria to kill mosquito larvae.

3) Prevention of bites ( best method )

• Use mosquito nets, soak mosquito nets in insecticide, mosquito repellent, don't expose skin when mosquito are active at dusk.

Malaria is endemic in TROPICAL AREAS and SUB-TROPICAL AREAS

Why ?

• The vector, the Anopheles mosquito, survives and breeds in hot and humid areas.

• Needs still / stagnant water to reproduce

• Plasmodium reproduces within the mosquito at > 20 degree celcius

• Eradicated outside tropics ( exp. USA, Italy )

2) Insecticides-resistant mosquitoes ) e.g. DDT )

• DDT is most common insecticide

• Insecticides used also killed other organisms

• Reduction in mosquito also caused lost in immunity to malaria in local community, making them more vulnerable when the disease returned.

3) Global warming has resulted in spread of mosquito

• More warm areas for mosquito to breed and survive