Plasmodium vivax infection is a major global health problem. This species of parasite has the broadest geographic distribution of the five malaria species known to infect humans [
1]. There are about 2.5 billion people at risk of malaria and an estimated 80 to 300 million clinical cases of
P. vivax annually [
2,
3]. Although
P. vivax is mainly endemic in Southeast Asia and Latin America [
3], it has recently been observed in Ethiopia and Sudan [
4‐
8].
Malaria is a important health problem in Sudan, and in 2002, an estimated 9 million disease episodes and 44,000 deaths from the disease occurred [
9]. The spread of multidrug-resistant
Plasmodium falciparum malaria in Sudan [
10,
11] has led to adoption of artemisinin-based combination therapy (ACT), with artesunate–sulphadoxine–pyrimethamine (AS–SP) and artemether–lumefantrine (AL) becoming the recommended first- and second-line treatments for uncomplicated
P. falciparum malaria, respectively.
Early diagnosis and effective treatment with an appropriate drug is one of the main components of the World Health Organization’s strategy to reduce malaria related mortality [
12]. Episodes of
P. vivax infection should prompt urgent treatment with effective anti-malarial medication [
13]. While most malaria endemic countries have adopted ACT to reduce the risk of multidrug resistant strains of
P. falciparum occurring [
10], chloroquine remains the first-line treatment for
P. vivax in most endemic countries. However, there is growing evidence that the efficacy of chloroquine against
P. vivax is declining in many areas, especially Southeast Asia [
14‐
16]. Hence, the use of ACT against both
P. vivax and
P. falciparum is preferred, especially in a country like Sudan where chloroquine is no longer registered or available [
17]. The far-reaching adoption of ACT as an effective first-line therapy for
P. falciparum has led to a closer examination of their role in the management of
P. vivax malaria. AL is one such combination therapy that is widely used to treat uncomplicated
P. falciparum malaria, and is the first-line treatment for
P. vivax malaria according to the national malaria control programme in Sudan. However, there is no published data on the efficacy of AL for the treatment of
P. vivax malaria in Sudan. Therefore, the efficacy of AL for the treatment of uncomplicated
P. vivax malaria was investigated in Sudan. The study was conducted at a health centre in eastern Sudan, an area characterized by unstable malaria transmission [
18]. Recently, however, the most severe form of
P. vivax malarial disease has been observed in the area [
8]. The study is of paramount importance because it aims to provide Sudanese health care professionals and public health planners with the fundamental data necessary for developing an effective programme for malaria control.