Plasmodium Types

P. Falciparum

• Plasmodium falciparum, or P. falciparum, is present in the blood as parasites called trophozoites. They form rings in the developmental stage without the full-grown parasites that mark the completion of the malaria and often death. Once the first stage, or ring stage, is complete, it is marked by more numerous P. falciparum parasites. They multiply and infect cells and grow into a crescent shape.

P. Vivax

• P. vivax enlarges and infects the blood. It appears in the shape of granules. These granules are known as "Schuffner's dots" and can be seen over the cell membrane and cytoplasm. Parasites called trophozoites, the markers of P. vivax, have an ameboid trait, and more than 20 merozoites are present.

P. Ovale

• P. ovale, like P. vivax, also displays the trait of Schuffner's dots and a mutated cell. It is difficult to distinguish the two at first, but P. ovale is a smaller parasite, without the crescent shape of P. vivax. The smallness can be seen during the growth in the early stages. There are also fewer components of the parasite in the infection.

P. Malariae

• P. malariae is known as a "compact parasite." It does not grow to a large size throughout the infection. It also does not change in composition throughout the infection. It is marked by long trophozoites of the parasite called "band forms." The presence of eight to 10 components of the parasite called merozoites causes a rosette shape and a clump with pigment in the center.