What is the reason of malignant malaria?

The reason of malignant malaria is infection of the human host by Plasmodium falciparum, a species of parasitic protozoans (sporozoa). The parasite is transmitted to humans via the bites of infected Anopheles mosquitoes. It is the most virulent of the five malaria parasites that infect humans, and is responsible for the overwhelming majority of malaria-related deaths worldwide.