Introduction: Acute febrile illness (AFI) is defined as a patient with fever of 38°C or higher at presentation or history of fever that persisted for 2-14 days with no localizing source. Fever is the main clinical symptom of various tropical infectious diseases [1] . Materials and Methods: This is a Prospective and observational study was conducted at Paediatric Department, Gayatri Vidya Parishad Institute of Health Care and Medical Technology over a period of 1 year. Acute febrile illness (AFI) is defined as a patient with fever of 38°C or higher at presentation or history of fever that persisted for 2-14 days with no localizing source. Details of history and results of a thorough physical examination were entered on a standard data collection sheet.The routine baseline investigations included complete blood count analysis, serum electrolytes, liver and renal function tests.