Why does malaria cause repeated fevers?

Malaria causes repeated fevers due to the synchronized life cycle of the Plasmodium parasite within the human body. After infecting red blood cells, the parasites multiply rapidly, eventually causing the cells to rupture.12

When these infected red blood cells burst, they release a new generation of parasites—known as merozoites—along with toxins into the bloodstream. This synchronized release triggers the body's immune response, resulting in the characteristic periodic attacks of chills and fever.12

The frequency of these fever cycles depends on the specific species of the parasite:
* 48-hour cycles (tertian malaria): Caused by P. falciparum, P. vivax, and P. ovale.12
* 72-hour cycles (quartan malaria): Caused by P. malariae.12
* 24-hour cycles: Caused by P. knowlesi, which can lead to daily fever spikes.12

If a patient is infected with multiple generations of parasites or different species simultaneously, these classic patterns may become irregular, leading to more frequent symptoms.2