Falciparum [fal-′sɪ-pə-rəm]

Figure

Figure. Giemsa-stained thin blood smear of Plasmodium falciparum (original magnification ×1,000). Red arrows indicate gametocytes, and green arrows indicate trophozoite stages. Photograph provided by A. Tiwari.

From the Latin falx or falci (sickle or scythe-shaped) and parum (like or equal to another) or parere (to bring forth or bear). The species falciparum in the genus Plasmodium is the parasite that causes malignant tertian malaria in humans (Figure).

There were many terms suggested for this parasite, such as Ematozoo falciforme by Antolisei and Angelini in 1890 and Haemotozoon falciforme by Thayer and Hewetson in 1895, because of its sickle-shaped gametocytes, the sexual stage of falciparum parasites. However, the term falciparum, suggested by William Henry Welch in 1897, was eventually accepted. In 1954, Plasmodium falciparum (previously Laverania malariae) was approved by International Commission on Zoological Nomenclature.