Table 1.

Study clinical case definition

Criteriona	Definition
Age	1 month – 15 years
Fever	≥38°C within 24 h of hospital admission
Clinical features	At least one of:  • Stiff neck  • Altered / reduced consciousness   o V, P, or U on the AVPU score   o <15 on the Glasgow Coma Score  • Focal neurological symptoms / signs  • Convulsions   o Aged <6 months or ≥6 years: any seizure   o Aged 6 months to <6 years: any focal or prolonged seizure OR ≥2 brief generalised seizures  • Bulging fontanelle if <12 months of age  • Irritability if <5 years of age  • Headache  • Prostration   o Inability to drink or breast feed, or to remain sitting in a child otherwise able to sit  • Petechial or purpuric rash
Laboratory investigation	Lumbar puncture performed, or actively planned at the time of assessment, by clinical team

^aFor study enrolment, all four criteria had to be met (age, fever, clinical, and laboratory)