Haynes CM, et al. Abstract 2744. Presented at: ASM Microbe; June 9-13, 2022; Washington, DC
Disclosures: Kotay reports no relevant financial disclosures.
WASHINGTON — Flushing hospital sinks just twice per week may help eliminate bacterial colonization and prevent the spread of harmful organisms to patients, according to researchers at ASM Microbe.
“We started back in 2016 when sink spread studies were prevalent. A lot of hospitals in Europe and the US in particular were tracking what’s happening in sinks and how colonization was getting established in sinks,” Shireen M. Kotay, PhD, a research associate in the division of infectious diseases and international health at the University of Virginia, told Healio, adding that there are now more than 100 publications on the topic.
“With that in mind, we did a demonstrative study to really try to understand the mechanism of how the spread happens,” he said.
Kotay and colleagues used model sinks to perform experiments assessing the impact of a faucet flush on bacterial colonization. They used green fluorescent protein-expressing Escherichia coli (GFP-E. coli) — an easy-to-track surrogate organism — in 10 sink drains and flushed them with water for 30 seconds at varying frequencies: none, once, twice, three times, seven times and 84 times (every 2 hours) per week. They monitored colonization in four areas of the drain.
They detected GFP-E. coli in all four areas when a flush was not performed or performed just once during the week. However, with a minimum of two flushes during the week, GFP-E. coli was below the detectable limit at the drain level.
“To have some significant level of reduction, you need at least two flushes per week. Anything more than that is good,” Kotay said, adding that even with a high flush frequency, the colonization did not go away completely. “This suggests that bacteria will still survive in the vertical part of the drain.”
Kotay said the data could be used to influence guidance. He explained that a newer hospital, for example, could use sinks with self-cleaning or smart programming, or the data could be used to influence guidance on practices or behaviors for manually flushing sinks.
The researchers plan to assess the impact of flushing on real-world sinks from hospitals with naturally occurring bacteria instead of model organisms.
“If you can keep the drain clean, much of the splatter causing spread to patients can be avoided,” Kotay said. “So, flush your sinks.”