Without an effective therapy or a vaccine for the novel coronavirus, the U.S. economy could face 18 months of rolling shutdowns as the outbreak recedes and flares up again, Federal Reserve Bank of Minneapolis President Neel Kashkari said.

“We’re looking around the world. As they relax the economic controls, the virus flares back up again,” Kashkari said Sunday on CBS’s “Face the Nation.” Kashkari is a voter in 2020 on the Fed’s policy-setting Federal Open Market Committee.

“We could have these waves of flareups, controls, flareups and controls until we actually get a therapy or a vaccine. I think we should all be focusing on an 18-month strategy for our health care system and our economy.”