Fig. 4: Genomics support of microbiological linkages among two participants.

Column headings indicate date, location, and type (baseline or follow-up = in-room; or interactive) of each study visit. Transmission events are identified with a red circle; single positive swabs not able to be assessed for transmission are identified with a blue circle. White circles outlined in gray are samples collected and negative for any MDRO; colored circles outlined in red are samples collected and positive for a particular strain (listed in each legend). a For participant 1002, VRE strain 10 was detected at multiple body sites (groin and hand) and environmental surfaces (bedrail and privacy curtain) at study baseline (Apr 26). Study staff attended a dialysis session with this participant on Apr 27, during which time the participant’s hand was colonized with VRE strain 10 at the start of the session, but no transmission of VRE to any surfaces was detected during that interactive visit. Study staff also attended a PT & OT combined session on that same day (Apr 27); during this interactive visit, a VRE strain 10 transmission (circled in red) was detected at the wrist weights, since the weight went from VRE-negative to VRE-positive following participant use. Based on our microbiology results, the participant’s hand is the likely source of this transmission, since the participant’s had was VRE-positive at the beginning of the interactive visit. Furthermore, sequencing confirms these VRE strains are identical. The healthcare provider hand at the end of the session was also VRE-positive; however, this is not counted as a transmission because we do not have a “before” swab on the healthcare provider hand to prove that it changed status from negative to positive. Sequencing results confirm this strain is identical to that carried on the participant hand, highly suggestive of transmission. This participant continued to be colonized, and their in-room surface contaminated, at two subsequent in-room visits. This participant’s hand was also colonized during two subsequent interactive visits, but no other transmissions were detected. b For participant 1001, VRE strain 12 was detected at multiple body sites (nares, groin, and hand) and environmental surfaces (bed control, bedrail, call button) at study baseline (on Apr 19). During the first in-room follow-up visit (Apr 26), VRE strain 12 was detected at the participant groin, table top, and privacy curtain, while VRE strain 13 was detected on the participant’s hand. During the next in-room follow-up visit (May 3), VRE strain 12 was detected only at the participant groin. Study staff next attended a PT session with this participant (May 5), during which time no MDROs were found on the participant’s hand, on surfaces, nor on the healthcare provider hand. The next visit with this participant was in his or her room (May 10), where VRE strain 13 was detected at the participant’s groin, hand, and TV remote, while VRE strain 12 was detected at the bed control. Study staff attend a PT session with this participant next (on May 10), during which time a VRE strain 12 transmission (circled in red) was detected at the exercise band, since the exercise band changed status from VRE-negative to VRE-positive following participant use. The participant’s hand was not positive for VRE at the start of this session, so we cannot assume the source of this transmission was the participant’s hand. However, sequencing allows us to speculate that the participant’s hand is the likely source, since their hand was colonized with VRE strain 12 at an earlier, in-room visit (on Apr 19). This participant continued to be colonized (VRE strain 13), and their in-room surface contaminated (VRE strains 13 and 31), at one subsequent in-room visit. This participant’s hand was not colonized at any subsequent interactive visits. Abbreviations: MDRO, multidrug-resistant organism; OT, occupational therapy; PT, physical therapy; VRE, vancomycin-resistant enterococci.