2017 HSR&D/QUERI National Conference

1078 — Healthcare Provider-Environment Interactions: Measuring Touch Frequency to Understand Their Role in Transmission of Healthcare Associated Infections

Lead/Presenter: Molly Leecaster, COIN - Salt Lake City
All Authors: Leecaster M (VA Salt Lake City IDEAS Center) Rubin M (VA Salt Lake City IDEAS Center)

The role of fomites in the transmission of healthcare associated infectious pathogens is not fully understood. Transmission is believed to occur, at least partially, through contact between healthcare providers (HCP) and the environment. Accurate estimates of frequency of contact linked to bioburden of hands and surfaces will enhance our understanding of the role of fomites and thus the importance of bioburden reduction in controlling transmission. We assessed the accuracy of touch frequency estimates based on a wireless sensor network (WSN).

Touch frequency data were collected using a WSN in unoccupied patient rooms within the Salt Lake City VA medical intensive care unit. The sensors send low frequency signals approximately 6 feet and record signals from other sensors in that range. Surface sensors send signals when they move. We varied the threshold of movement necessary to trigger a signal. Surface sensors were placed on the over-bed table, computer keyboard, IV stand, touchscreen, sink, soap dispenser, gel dispenser, and patient bed. Study personnel wore sensors that record signals and interacted with these surfaces as if they were HCP. Actions were repeated 2-6 times per session for up to ten sessions. We calculated sensitivity and positive predictive value (PPV) of the sensor data compared to video recording of the actions.

There were 20 to 50 actions for each surface type performed during the sessions. The sensitivity and PPV both ranged from 0.8 to 1.0. Gel and sink use had the highest accuracy and table movement had the lowest. Thresholds were set to record even slight vibrations for the keyboard, sink, IV stand, and table. Thresholds for the touchscreen, soap, bed, and gel were set to require greater vibration to trigger a signal.

The WSN, which is quick to deploy and collects time-stamped data continuously, can be used to collect accurate data on surface touch frequency in patient rooms.

The WSN will be deployed continuously during a study collecting microbiologic samples from HCP hands and patient room surfaces. The paired data will be used to estimate model parameters and simulate transmission to better understand the role of fomites and the effect of interventions.