This is a legitimate question for healthcare and other critical needs professions that are asked to stay on at a facility, or quarantined longer than a year in one geographic area (metro, not state).
The reason this is important is that per diems are taxable after one year of service in the same metro area.
Currently, none of the recent legislation has changed this rule, although an influential tax law firm reached out in early March with the suggestion ( see Request to Liberalize Away From Home Rules see page 5-6).
As of March 26, 2020, there has been no change in policy.
Stay tuned for further developments.