The Joint Malaria Programme together with the London School of Hygiene and Tropical Medicine have recruited severe malaria cases and healthy controls to contribute to Consortial Project 1. These individuals have been collected from Muheza, north east Tanzania, where P. falciparum transmission is intense (50 to 700 infected bites/person/year) and perennial with two seasonal peaks.

Description of study population - Cases

Cases consist of children (3 months-10 years) admitted to hospital with signs of severe malaria. These children were recruited from Teule Hospital in Muheza, a district hospital serving a rural population of approximately 277,000 with child mortality of 165/1,000 between June 2006-May 2007.

Consecutive daytime admissions were triaged for the need for emergency treatment and then screened for study eligibility. Inclusion criteria were: age 2 months to 13 years with a history of fever within the previous 48 hours. Children with an obvious non-infectious cause for admission such as trauma, surgery or known malignancy were excluded. Following consenting procedures, the criteria for entry was asexual P. falciparum parasitaemia and any of the following: more than 2 seizures in the previous 24hrs (mothers history); Blantyre coma score <3 (repeated if BCS<5 and convulsion within 1 hr or anticonvulsant given within 6 hrs); prostration (inability to sit unsupported or, if age<8months, inability to drink);  respiratory distress (deep breathing or low chest wall indrawing or respiratory rate>70 bpm or O2 sat<90%); jaundice (inspection of sclera); severe anaemia (haemoglobin <5g/dL); blood glucose <2.5mmol/L; blood lactate >5mmol/L.

Description of study population - Controls

Controls consist of healthy children (1-10 years) recruited between July 2007 and August 2008. These were individually matched to cases for tribal origin of at least one parent, electoral ward of residence and within 3 years of age to a case. Potentially eligible controls were initially identified by the healthworker in the local primary care clinics. These children were later visited by research staff and the ethnicity match was confirmed on interview with one of the parents. The following eligibility criteria of the child were then checked: not admitted to Teule hospital for severe malaria in the previous 12 months; aged between 1-13 years; and was aged within 3 years of the case; good health (i.e. eating and drinking normally and playful); haemoglobin >8 g/dl; no skin condition or other impediment to obtaining a venous blood sample.