Understanding Log Reduction: Decoding the Numbers for Smarter Infection Prevention

Session Description: Log reduction is one of the most widely cited measures of microbial control, yet it is often misunderstood, miscommunicated or misapplied in healthcare settings. Infection Preventionists (IPs) are routinely presented with claims of “99.99% effectiveness” or “6-log kill” when evaluating disinfectants, sterilization processes, and new technologies. Without a clear understanding of what these numbers represent and what they do not guarantee, it becomes difficult to make informed decisions.

This session will demystify log reduction by breaking down the science into clear, practical terms. Participants will learn what each log reduction level actually represents in terms of microbial survival, why the difference between 3-log and 6-log matters, and how these figures are determined under laboratory conditions. The session will also highlight the limitations of relying solely on log reduction data, including the impact of organic load, environmental factors, and deviations from manufacturer instructions for use.

Using real world examples, attendees will explore scenarios where impressive log reduction results in lab testing did not translate into meaningful infection prevention outcomes. Guidance will be provided on how to interpret manufacturer claims, ask critical evaluation questions, and communicate findings effectively to both leadership and frontline staff.

By the end of the session, participants will be equipped to use log reduction data as a tool not just a talking point. This will ensure that technology and process decisions are grounded in both evidence and context.

Aaron Woodall

Chief, Infection Prevention and Control, Department of Veterans Affairs

Aaron A. Woodall is an infection preventionist with nearly two decades of global experience. His career began in military combat medicine and public health efforts across Eastern Afghanistan, Europe, Middle East and Africa. His expertise spans many diverse healthcare environments.

Silvera Ford

Infection Prevention Nurse 3, The University of Kansas Health System

Silvera Ford is a Board-Certified Infection Preventionist at The University of Kansas Health System. In this role, she collaborates across disciplines to ensure patients are cared for in a manner that prevents the spread of infection. Preventing infections is her passion. Some of her responsibilities include partnering with perioperative and procedural areas, construction liaison and overseeing the quality assurance program for high level disinfection. For the last twenty-three years, Silvera has been an Infection Preventionist during which time she has been an active member of the local and national Association of Professionals in Infection Control (APIC). Silvera is currently the Past-President for the local Greater Kansas City APIC Chapter and member of the national APIC Annual Conference Committee. She also has experience in presenting to diverse audiences at the local, national and international levels.