Criteria: Inclusion Criteria:  Clinical suspicion of an acute infectious disease  Presence of at least ONE of the following:  Temperature ≥ 38°C or Temperature ≤ 36°C Heart rate > 90 bpm Respiratory rate > 20/min Self reported fever/chills Symptom duration ≤ 7 days  Exclusion Criteria:  Received antibiotics or antivirals in the past 2 weeks. Previous infection in previous 2 weeks Primary or secondary immunodeficiency Proven or suspected HIV, hepatitis B or hepatitis C infection Current immune-suppressive or immune-modulating treatment Active hematological malignancy Other illnesses that affect life expectancy