Defense Secretary Mark Esper has issued a stop movement order to the U.S. military halting travel and movement abroad for up to 60 days in an effort to limit the spread of the coronavirus through the ranks, the Pentagon chief told Reuters on Wednesday.

The measure is by far the Defense Department’s most sweeping to date and will affect forces around the world. Esper said in an interview that the order applied to all U.S. troops, civilian personnel and families, but noted that there would be some exceptions.

“The purpose is to make sure that we’re not bringing the virus back home, infecting others, that we’re not spreading it around the military,” Esper said.

Esper said one exception to the order would be the drawdown under way in Afghanistan, which will continue. The United States has said it is committed to reducing the number of its troops in Afghanistan to 8,600 from 13,000 within 135 days of signing the deal with the Taliban last month.

A full withdrawal of all U.S. and coalition forces would occur within 14 months of the deal getting signed, if the Taliban holds up its end of the deal.

“That (stop movement order) should not impact that,” Esper said of the withdrawal.

The stop movement order illustrates the Pentagon’s increasing concern about the rapid spread of the virus, which has already infected 227 U.S. troops – a figure that has climbed by about 30 percent in just the past day.

The U.S. military said earlier on Wednesday it was also elevating its health protection condition, or HPCON, at bases around the world to Charlie, its second highest level, which suggests sustained community transmission.