Background: Nosocomial infection is an important public health problem in Brazil. The better to understand and address this problem, we began using the National Nosocomial Infection Surveillance (NNIS) system in five Brazilian hospitals in 1991.
Methods: Data were collected prospectively according to the NNIS protocol, by using nosocomial infection definitions from the Centers for Disease Control and Prevention.
Results: From January 1991 to June 1995, the overall nosocomial infection rate was 5.1% or 9.7 nosocomial infections/1000 patient-days. From the detailed epidemiologic information obtained by using the NNIS methods, interventions were designed and implemented that have reduced specific nosocomial infection rates. For example, the incidence of infection caused by methicillin-resistant Staphylococcus aureus was reduced from 0.61 infections/1000 patient-days in 1991 to 0.05 infections/1000 patient-days in 1996 (p < 0.01). The surgical site infection rate after cesarean section was reduced from 11.6% in 1993 to 5.9% in 1996 (p < 0.05). Cost savings from a program to optimize the use of antimicrobial agents in one hospital was more than $1.8 million over a 45-month period.
Conclusion: The NNIS method was applicable in a wide variety of hospitals, even those with little or no experience with nosocomial infection surveillance. By using this method, we defined the detailed epidemiology of nosocomial infection and implemented interventions that have significantly reduced nosocomial infection rates while achieving substantial cost savings.