Patients enrolled in surveillance
During January 2013 to December 2015 we enrolled 10,602 individuals of which 10,149 (95.7%) had available data on age and underlying medical conditions as well as respiratory viruses and HIV results and were thus included for further analyses. Of these 10,602 individuals, 2,119 (20.9%) were controls, 3,672 (36.2%) were outpatients with ILI and 4,358 (42.9%) were inpatients with SRI. Children aged <5 years accounted for 38.0% (806/2,119) of controls, 35.5% (1,134/3,672) of patients with ILI and 37.5% (1,632/4,358) of patients with SRI. The HIV prevalence was 41.3% (874/2,119) among controls (due to enrolment criteria), 25.1% (923/3,672) among patients with ILI and 50.1% (2,183/4,358) among patients with SRI.