Prevalence of nosocomial infections in 15 Italian hospitals: first point prevalance study for the INF-NOS project.

Background: The aim of our study was to assess the magnitude of nosocomial infections (NI) in 15 Italian hospitals. Patients and Methods: A multicenter point prevalence study of NI was carried out in October 2001 among eight medical, surgical and intensive care units in hospitals with more than 400 beds, after a pilot phase performed in April 2001. Results: Of the 2,165 surveyed patients, 163 had a total of 179 NIs. The global prevalence rate of patients with NI and of NI was respectively 7.5% (95% CI 6.4-8.6) and 8.3% (95% CI 7.1-9.4), ranging from 5.5% (95% CI 4.2-6.8) in medical wards to 34.2% (95% CI 25.7-42.7) in intensive care units (ICUs). The NI prevalence was higher in: - hospitals that did not have an infection control committee (ICC) compared to hospitals with an ICC (10.3%, 95% CI 6.4-10.1 versus 7.2, 95% CI 6.0-8.3, p = 0.08), - university hospitals compared with non-teaching hospitals (9.4%, 95% CI 4.5-14.2 versus 7.4%, 95% CI 6.3-8.5, p = 0.4) and - hospitals with 1,000 or more beds compared to lower volume hospitals (9.5%, 95% CI 7.3-11.7 versus 6.6%, 95% CI 5.3-7.8, p = 0.02). The most prevalent infections found were lower respiratory tract infections, urinary tract infections and surgical-site infections, representing 38.0%, 20.1% and 12.8%, respectively, of all NI. Among 1,674 patients without any infection, 575 (34.3%) of them had been undergoing antibiotic treatment at the time of the survey. Conclusion: The high rate of NI, particularly in ICUs, and the high number of improper procedures emphasize the need to develop clinically-oriented guidelines, tailor active infection control programs and implement an active ICU surveillance system.