Health care-associated infection impact with bioaerosol treatment and COVID-19 mitigation measures

Ereth, Mark H.; Fine, Judith; Stamatatos, Frank; Mathew, Bency; Hess, Donald; Simpser, Edwin

BACKGROUND: The real-world impact of breathing zone air purification and COVID-19 mitigation measures on health care-associated infections is not well documented. Engineering solutions to treat airborne transmission of disease may yield results in controlled test chambers or single rooms but have not been reported on hospital-wide applications and the impact of COVID-19 mitigation measures on health care-associated infection rates is unknown. AIM: To determine the impact of hospital-wide bioaerosol treatment and COVID-19 mitigation measures on clinical outcomes. METHODS: In a live 124 bed hospital (>100,000 patient days over 30 months) we documented the impact of the step-wise addition of air disinfection technology and COVID-19 mitigation measures to standard multi-modal infection control on particle counts, viral and bacterial bioburden, and health care-associated infection rates. FINDINGS AND CONCLUSION: The addition of air-disinfection technology and COVID-19 mitigation measures reduced airborne ultrafine particles, altered hospital bioburden, and reduced health care-associated infections from 11.9 to 6.6 (per 1,000 patient days) and from 6.6 to 1.0 (per 1,000 patient days) respectively (P< 0.0001, R(2)= 0.86). No single technology, tool, or procedure will eliminate health care-associated infections but the addition of a ubiquitous facility-wide engineering solution at limited expense and with no alteration in patient, visitor, or staff traffic or work flow patterns reduced infections by 45%. A similar impact was documented with the addition of comprehensive, restrictive, and labour and material intensive COVID-19 mitigation measures. We believe this is the first direct comparison between traditional infection control, an engineering solution, and COVID-19 mitigation measures.