Monitoring the rate of hospitalization before rotavirus immunization in Italy utilizing ICD9-CM regional databases

Regional HDD databases from Piemonte, Veneto, Friuli-Venezia-Giulia and Marche were analyzed. A total of 434,335hospitalizations were counted in the study timeframe and 13,234 VE diagnoses (3% of hospitalizations) were collected. A total of 8546 RVE cases (2% of hospitalizations, 64% of all VE) were observed, of which 1.2% were primary diagnoses (PD) and 0.8% secondary diagnosis (SD). The RVE hospitalization peak (4.9 %) was observed at the age of 1 year (4.5% in 7–12 months of age)with a median hospital stay of 4.4 days (s.d ± 4.2). Two deaths (out of 8546 RVE cases) were identified.The primary objective of the study was to estimate the frequency of hospitalization for VE and RVE in children aged less than or equal to 5 years between 2001 and 2005. The secondary objectives were to describe the rates of primary (PD) and secondary (SD) diagnosis both for VE and RVE, main diagnostic/therapeutic procedures, outcomes and RV Diagnosis Related Group (DRG) codes.