Malaria in the human body is caused by which one of the following organisms ?

Malaria is an infectious disease caused by protozoan parasites belonging to the genus Plasmodium [1][t1]. While mosquitoes, specifically the female Anopheles species, are the vectors responsible for transmitting the disease to humans through their bites, they are not the causative organisms themselves [c1][t2]. Once the mosquito injects the parasite into the human bloodstream, it targets the liver and red blood cells, leading to symptoms such as periodic chills, high fever, and anemia [c2][t7]. There are five primary species of this protozoan that infect humans: P. falciparum, P. vivax, P. ovale, P. malariae, and P. knowlesi [t4][t8]. Unlike bacterial or viral infections, malaria is strictly parasitic in nature, requiring both a vertebrate host and an insect host to complete its complex life cycle [t6][t10].

Sources

1. [1] Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 8: Natural Hazards and Disaster Management > Malaria > p. 78