Nosocomial Infections Outbreaks in Chile 1985–2002

BACKGROUND: Ministry of Health developed a nosocomial infection (NI) program based on surveillance, guidelines, and evaluation. By regulation, hospitals have reported NIOs since 1985. METHODS: We analyzed information by patient, site, agent, and trend. We compared mortality using χ2 and trend by correlation coefficient. RESULTS: There were 711 NIO notified between 1985 and 2002, comprising 5210 cases (average 7.3 cases per NIO), mortality 8.2%. Of these, 67.8% occurred in pediatrics patients, and 1.3% affected hospital staff. The main sites in pediatrics were gastrointestinal (38.8%), varicella (18.0%), and blood (8.0%). In adults they were deep infections (26.7%), skin (18.5%), lower respiratory (18.5%), and surgical (16.9%). The main areas in pediatric services were infant and school-age wards (33.7%) and neonatology (33.1%); among adults, main areas were surgical (20.9%), ICU and medical (19.0% each). S. aureus caused 17.5% of NIO, 5.1% were MRSA, 11.4% were E. coli, 11.2% were Varicella, and 9.4% were A. baumannii. Mortality was higher in adults (RR1.06 IC95% 1.04–1.08 p<0.05). More than two-thirds (67.3%) of NIOs were caused by inadequate practices, and 1.8% were caused by carriers. NIO have decreased notably during the last decade, from 110 NIO in the 1980s to 25 in the 1990s (R2 0.6259 p<0.05). The main decrease was in diarrhea and varicella. Proportionally, NIO involving MRSA and Acinetobacter have decreased with an increase in viral etiology. Mortality increased around 10% and is associated with deep infections. CONCLUSIONS: NIO have decreased 77% in the period. They are frequently found in pediatric patients (including neonatology). Mortality is higher in adults. Most NIO are related to inadequate practices. Knowledge of NIO is essential to provide information useful for local intervention programs.