How many Plasmodium (malaria) species are there?

How many Plasmodium (malaria) species are there?

• A. 2
• B. 3
• C. 4
• D. 5

Answer: (C)

Four Plasmodium species are classically recognized as infecting humans: P. falciparum, P. vivax, P. malariae, and P. ovale. This count reflects traditional medical teaching and exam material, where these four are the species most commonly associated with human malaria. Each has distinct clinical features—P. falciparum often causes the most severe disease, P. vivax and P. ovale can relapse due to dormant liver stages, and P. malariae tends to cause a quieter, quartan fever pattern. In newer findings, another species, P. knowlesi, can infect humans in some areas, but the standard count used in many assessments remains four.

Four Plasmodium species are classically recognized as infecting humans: P. falciparum, P. vivax, P. malariae, and P. ovale. This count reflects traditional medical teaching and exam material, where these four are the species most commonly associated with human malaria. Each has distinct clinical features—P. falciparum often causes the most severe disease, P. vivax and P. ovale can relapse due to dormant liver stages, and P. malariae tends to cause a quieter, quartan fever pattern. In newer findings, another species, P. knowlesi, can infect humans in some areas, but the standard count used in many assessments remains four.