West Virginia Gov. Jim Justice on Monday issued a stay-at-home order directing all state residents to isolate in their homes and limit movements beyond essential needs in an effort to prevent the spread of the coronavirus.

The order, which goes into effect Tuesday at 8 p.m., makes West Virginia the latest in a growing number of states to enact strict shelter-in-place measures as the number of cases nationwide grows exponentially.

Justice, a Republican, pointed to a number of factors behind the decision, including a new coronavirus case discovered in a nursing home worker that was the result of community transmission. He also said that stay-at-home directives in surrounding states could push out-of-state residents to flock to West Virginia – something he did not want to happen.

Sixteen people have tested positive for the coronavirus in the state, Justice said. It is the fewest number of cases identified in any U.S. state.

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Under the order, residents can leave their homes to run essential errands like going to the grocery store, doctor or pharmacy, or to go to work if they work at an essential business. Restaurants will remain open for take-out and delivery, and residents are allowed to exercise outdoors or travel to care for a friend or family member. It is not clear if or how the state will enforce the measure.

Justice on Monday urged residents to take the virus seriously, saying that it was unlike any event any living person on earth has experienced.