The parasite passes from one human to another via a female Anopheles mosquito which hands it on when the insect takes a blood meal. Hemera
From Discovery News:
The parasite that causes the most lethal strain of malaria among humans crossed the species barrier from gorillas, scientists reported on Wednesday.
Plasmodium falciparum is the deadliest of the five known strains of malaria parasites, causing several hundred million cases each year, of which around a million are fatal.
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