RESUMEN
BACKGROUND: Hand hygiene is the most important measure to reduce health care-related infections and colonization with multiresistant micro-organisms. We sought to determine the rate and seasonality of handwashing compliance in a university-affiliated hospital. METHODS: In January 2006 (baseline period), handwashing observation was first made in an intensive care unit. From March to May 2006, there was an intervention period; and, from June 2006 to August 2009, we followed hand hygiene compliance. Seasonality curves for handwashing compliance were made during follow-up period. RESULTS: During baseline period, a total of 166 observations was made. During follow-up, 17,664 opportunities for hand hygiene were observed. Compliance improved from 30.0% to a mean of 56.7% after the intervention (P < .001). The highest mean rate of compliance was 77.9% for nurses, compared with 52.6% for technicians (P < .001) and 44.6% for physicians (P < .001). Compliance was lower during summer days (first trimester of the year) and increased after March and April and slowly decreased through the end of the year. CONCLUSION: One of the reasons for the lower handwashing compliance in the first 3 months of the year is that, in Brazil, this is the summer vacation time; and, because of that, the staff's workload and the number of less well-trained personnel are higher. We emphasize the importance of continuously monitoring hand hygiene to determine the seasonal aspects of compliance.