**1. Introduction**

Malaria is a serious infectious disease. It is caused by parasites of the genus *Plasmodium* and transmitted by *Anopheles* mosquitoes to its vertebrate hosts. This disease is an important global health problem, especially in sub-Saharan Africa [1] (**Figure 1**). Indeed, the African region continues to carry a disproportionately high share of the global malaria burden [1, 2]. Among five *Plasmodium* species which infect human, two species *Plasmodium falciparum* and *Plasmodium vivax* pose the greatest threat for human health. For example, *P. falciparum* is the most prevalent malaria parasite on the African continent. It is responsible for most malaria-related deaths globally [3], while *P. vivax* is rare in sub-Saharan Africa, but it is the major malaria parasite in most countries outside of sub-Saharan Africa [4].

The origin of parasites responsible of human malaria has always been at the center of the debate [5, 6]. Understanding the origin of its infectious agents could open a door in the improvement of strategies to fight against the malaria agents which constantly surprise us by their abilities to adapt to the different means of fight put in place. So then, the questions are as follows: *Where do the pathogens* 

**Figure 1.** *Map of world malaria distribution.*

*responsible for this disease come from in humans*? This chapter is a synthesis of the available data on the origin of two most virulent agents of human malaria: *P. falciparum* and *P. vivax*.
