Validation of Vital Signs and Symptoms for the Diagnosis of Serious Infections in Acutely Ill Children in a High Prevalent Setting: The Paediatric Accidents & Emergencies through prospective observational data collection concerning specific items from the clinical and technical examination in diagnosing serious infections, such as meningitis, sepsis, pneumonia, pyelonephritis, bronchiolitis with hypoxia. Eventually we will attempt to validate a vital signs and symptoms rule derived from multiple low to high prevalent settings of acutely ill children.

Inclusion Criteria:

• Children aged 1 month to 16 years
• Acute illness episode of maximum 5 days

Exclusion Criteria:

• recent trauma
• neurological conditions
• intoxication
• psychiatric of behavioural disorders without a somatic cause
• acute exacerbation of a chronic condition (asthma, known immunodeficiency, diabetes, cystic fibrosis, etc)

Children aged 1 month to 16 years, attending the A&E department of the UZLeuven Hospital with an acute illness episode of maximum 5 days