1. Department of Emergency Medicine , Children’s Clinical University Hospital , 45 Vienības Av ., Rīga , , Latvia
2. Department of Pediatrics , Rīga Stradiņš University , 45 Vienības Av ., Rīga , , Latvia
3. Department of Infectiology , Children’s Clinical University Hospital , 45 Vienības Av ., Rīga , , Latvia
4. Department of Public Health and Epidemiology , Rīga Stradiņš University , 9 Kronvalda Blvd ., Rīga , , Latvia
5. Institute of Public Health , Rīga Stradiņš University , 9 Kronvalda Blvd ., Rīga , , Latvia