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St. Mary’s Hospital Study Finds Advanced Air Purification Technology Reduced Health Care Associated Infections, Including COVID, by 45%

Active particle control — **Figure 1.** Active Particle Control mechanism of action.

A new scientific study published this month in The Journal of Hospital Infection finds cutting-edge air purification technology installed at St. Mary’s Hospital for Children reduced healthcare-associated infections (HAIs), including COVID, by 45%. The study, which took place over a three-year period and was already underway when the COVID-19 pandemic hit, is thought to be the first of its kind, examining the impact of advanced air purification technology in a real-world hospital setting.

The study results provide a window into the significant advances that could be made in reducing the transmission of airborne viruses and bacteria in hospitals. According to the U.S. Centers for Disease Control and Prevention (CDC), HAIs account for an estimated 1.7 million infections and 99,000 associated deaths each year. Beyond hospitals, the findings point to a proven solution for reducing the spread of COVID-19 in other indoor settings, such as schools, restaurants, and commercial office buildings, where the risk of transmitting the virus is the highest.

“At a time when the FDA and health care professionals are demanding real-world evidence and with the pandemic as a backdrop, we’re very proud to have been able to conduct and publish these real-world results on the impact of this technology in disinfecting breathing zone air,” said Judith Fine, MSc, MPH, director of infection control for St. Mary’s.

“This progress reflects the extraordinary commitment from our entire staff and their desire for comprehensive infection control” said Dr. Edwin Simpser, president and CEO, St. Mary’s Healthcare System for Children.

The study was conducted over 30 months with more than 100,000 patient-days. Following implementation of advanced air purification technology, HAIs at St. Mary’s went from an average of 11.9/1,000 patient-days to an average of 6.6/1000 patient-days — a 45% reduction. Wound infections were found to fall by 63% and tracheal infections by 89%. When COVID-19 mitigation measures were added early in the pandemic, infections dropped another 47%.

These results were made possible with the rooftop, facility-wide installation of Active Particle Control (APC) technology from SecureAire. Current air purification technology, including HEPA filters, fail to eliminate most particles less than three microns from the breathing zone space. COVID-19, other viruses, bacteria, fungi, and volatile organic compounds (VOCs) are all smaller than 3 microns and are not affected by airflow. APC technology uses charged particles to force contaminants less than 3 microns to cluster together, increasing their size and mass, making them susceptible to airflow. These larger conglomerations of particles are then moved to the APC filter, where they are inactivated and destroyed.

Figure 2. Study design: progressive infection control measures.

Mark Ereth, M.D., Emeritus Professor, Mayo Clinic College of Medicine, and chief medical officer, SecureAire Technologies LLC, stated: “Eliminating hospital associated infections is a top priority for health care systems and federal regulators. This critical breakthrough in air purification represents an unobtrusive, affordable engineering solution for hospitals and other care facilities to consider when working to protect their patients, visitors, and staff. HEPA technology may have been sufficient in 1945, but it no longer meets the needs of hospitals in the 21st century. This innovation is long overdue and now has demonstrated its effectiveness in the first real-world trial in history.”

Figures 3, & 4. Tracking the results of the health care-associated infections on-site.

“Bacterial spores, like anthrax and clostridium, represent some of the biggest challenges to disinfection of our built environments,” said Mark Hernandez, Ph.D, professor and director, environmental engineering microbiology and disinfection at the University of Colorado Boulder. “The ability to inactivate these types of microbes, which SecureAire technology has done, indicates successful disinfection of many nosocomial airborne pathogens, including bacteria and viruses.”

The full study is available here: https://www.sciencedirect.com/science/article/pii/S0195670121002693.