The Army's chief of staff said the field hospitals in Seattle are now on a 48-hour prepare-to-deploy order.
The U.S. Air Force is testing whether it can transport dozens of people onboard its aircraft without first isolating them.
It is working with FEMA and the Department of Health and Human Services to determine the next virus hot spots.
The field hospital set up by the Army in Seattle's pro football stadium is shutting down without ever seeing a patient.
The centers were originally expected to take patients with non-COVID-19 conditions to relieve pressure from hospitals.
Less than half of the 2,000 ventilators the DoD promised have been allocated, despite a desperate need across the country.
The service will operate under a "reset" to determine which ops are necessary and which it can forgo until a later date.
The Defense Department is preparing to send them to states overwhelmed by the rising pandemic death toll.
The 531st Hospital Center was headed to New York, which is struggling to deal with number of coronavirus cases.
Sites in New York, California and Seattle are among those on the list.