The Malaria Research and Training Centre (MRTC) in Mali have recruited malaria cases, healthy controls and a small number of parents of cases to contribute to Consortial Project 1. Five main patterns of malaria transmission have been recognised in Mali: a zone of long seasonal transmission from 4-6 months between June and November in the south corresponding with the soudano-Guinean area where parasite prevalence is higher than 75%; a zone of short seasonal transmission from 3-4 months corresponding to the areas of savanna north-soudanienne and the Sahel where parasite prevalence varies between 50-75%; a zone of sporadic even epidemic transmission in the sub-Sahara area in the north where parasite prevalence is lower than 5%; the Niger river and areas of retained water and rice growing where transmission is bimodal or even multi-modal with a parasite prevalence lower than 40%; and urban areas where parasite prevalence is lower than 10%. Plasmodium falciparum is the dominant species and Anopheles gambiae s.l and A. funestus are the main vectors.

Description of study population - Cases

Cases consist of children (3 months-14 years) with signs of severe or uncomplicated malaria. Severe malaria cases were recruited from the pediatric ward at the reference hospital of Gabriel Touré in Bamako, the capital of Mail, between November 2006 and January 2008. A small number of uncomplicated malaria cases were also collected, matched to a severe malaria case by age (+/- 6 months), ethnicity, place and duration of residence.

Severe malaria was defined by the presence of P. falciparum parasitemia or optimal test positive and one of the following: coma (Blantyre coma score of less than 3) without other explanations (e.g. no evidence of pyogenic meningitis), anemia (haemoglobin <5 g/dL or hematocrit < 15%) without evidence of other causes (e.g. kwashiorkor).

Description of study population - Controls

Controls consist of healthy children (5 months-14 years) with no personal history of severe malaria. Controls were individually matched to a severe malaria case by age (+/- 6 months), ethnicity, place and duration of residence. To select controls, the research team visited the home of cases the day after enrollment and sought an unrelated child whose age, ethnic and residence duration matched that of the index case.

Description of study population - Parents

Blood samples from a small number of parents of severe malaria cases were collected.