Participant Eligibility Criteria
acute febrile disease, infections, fever
RECRUITMENT, INFECTIONS, RESPIRATORY TRACT INFECTION (RTI)
All children and adolescents from 6 months to less than 18 years attending the outpatient clinics of the 2 medical centers, with acute febrile disease defined as fever (current or within the past 7 d) with no focus or suspected respiratory tract infection (RTI), were eligible to be enrolled in the study. In addition, parents or guardians of participants consented and expressed their willingness to provide blood and other biological samples (dependent on current infections), to adhere to study procedures, and to return for follow-up visits at the recruitment facilities on day 7 (±2 d) [