SAN DIEGO – The overall prevalence of health care–associated infections among inpatients in the United States stands at 4%, with the most common types of infections being a combination of pneumonia and lower respiratory infections.
Those are key preliminary findings from the Centers for Disease Control and Prevention’s first large-scale health care–associated infection (HAI) prevalence survey in more than 30 years, Dr. Shelley S. Magill reported during IDWeek 2012, the combined annual meetings of the Infectious Diseases Society of America, the Society for Healthcare Epidemiology of America, the HIV Medicine Association, and the Pediatric Infectious Diseases Society.
The data "can help us better understand the factors that influence HAI prevalence," said Dr. Magill of the division of health care quality promotion at the Centers for Disease Control and Prevention, Atlanta. "We can also clarify the burden of different HAI types and pathogens across the hospital, which can suggest areas to target for prevention."
The phase 3 survey was conducted in 2011 in 183 hospitals in 10 states: California, Colorado, Connecticut, Georgia, Maryland, Minnesota, New Mexico, New York, Oregon, and Tennessee. Dr. Magill reported results from 11,282 patients who were surveyed in the 183 hospitals. Of these, 452 patients had HAIs, for a prevalence of 4%.
The researchers identified 504 HAIs in the 452 patients. Of these, the highest proportion (26%) were pneumonia or lower respiratory infections. "Of the pneumonia events, 39% were ventilator-associated infections," Dr. Magill said.
Surgical-site infections were the second most common infection type, representing 22% of all HAIs, followed by GI infections (17%), urinary tract infections (13%), and bloodstream infections (10%). "About two-third of UTIs were catheter associated and about 84% of the bloodstream infections were central-line associated," Dr. Magill noted.
Other infections made up the remaining 12% of HAIs.
Dr. Magill also reported that 56% of HAIs were attributed to non-ICU locations in the hospital while 53% were not directly associated with a device or with a procedure.
After multivariable regression analysis, patients with the following factors were at higher risk of having HAIs:
• Older age (risk ratio, 4.60 for patients older than age 77 compared with patients younger than 3 months old).
• Inpatient in a large hospital – defined as having 400 or more beds (RR, 1.24).
• Inpatient in a critical care unit (RR ,1.96 compared with all other units),
• Inpatient for more than 2 weeks at the time of the survey (RR, 26.09 compared with patients in the hospital for 3 days or fewer).
Pathogens were reported for 372 of the 504 HAIs. Clostridium difficile was the most common pathogen, accounting for 12% of all HAIs that were identified. Staphylococcus aureus was the second most common pathogen (11%; about half of these cases were methicillin-resistant S. aureus), followed by Klebsiella pneumoniae and Klebsiella oxytoca (10%).
Dr. Magill acknowledged certain limitations of the survey, including the fact that a small number of patients surveyed in each hospital "make results of limited use to individual facilities," she said. "We also had a relatively small number of hospitals in 10 states participate. This survey method provides a single snapshot of HAIs based on a retrospective review of medical record data, which is sometimes not complete. Finally, we were not able to collect a lot of detailed patient information, such as underlying illnesses and severity of illness."
She and her associates are currently planning a phase 4 survey, anticipated to occur in 2014.
Dr. Magill said she had no relevant financial conflicts to disclose.