When a senior living facility in Amarillo, Texas suspected a Nurse may have caught the novel coronavirus this month, it had a list within five minutes of staff and residents the nurse could have infected.

source https://www.reuters.com/article/us-health-coronavirus-wearables-tracing/elderly-home-turns-to-wearables-for-contact-tracing-sidestepping-apple-google-limits-idUSKBN22V2T0?feedType=RSS&feedName=technologyNews