The 2006 National Prevalence Survey (ENP) of healthcare-associated infections (HAIs) aimed to measure the prevalence on a given day and to describe the characteristics of HAIs and antimicrobial treatments in French healthcare facilities (HCFs). In June 2006, 2,337 HC participated, involving 358,353 patients; 17,817 (4.97%) patients were infected, 19,294 (5.38%) HIs were identified, and 55,624 (15.52%) patients were treated with antibiotics. Three infection sites accounted for nearly 60% of HIs: urinary tract infection, pneumonia, and surgical site infection. The three most common microorganisms were Escherichia coli, Staphylococcus aureus (52% of which were methicillin-resistant, MRSA), and Pseudomonas aeruginosa. Five antibiotics accounted for half of the prescribed agents: amoxicillin/clavulanic acid, ofloxacin, amoxicillin, ceftriaxone, and ciprofloxacin. The most common indications for treatment were community-acquired infection, hospital-acquired infection, and, less frequently, surgical antibiotic prophylaxis or prophylaxis against opportunistic infections. A comparison of the results from the 2001 and 2006 ENP surveys suggests a decrease of more than 10% in the prevalence of infected patients and more than 40% for patients infected with MRSA, which supports the impact of plans to combat hospital-acquired infections and multidrug-resistant bacteria. The prevalence of patients treated with antibiotics, however, has remained stable and warrants intensified efforts to promote the appropriate use of antibiotics in hospitals. (R.A.)