“How long does coronavirus last in saliva that is on an envelope?” asked Kim Wyman, the secretary of state in Washington, the state hardest hit by the virus so far.

Washington votes by mail, which eliminates most concerns about viral transmission, but also creates some. “We’re telling all of the people who handle incoming ballots to use gloves,” Ms. Wyman said. “We’ve also had a recommendation from National Guard: ‘Folks, you might consider masks.’”

Voters have been advised to use a wet sponge or cloth to seal envelopes rather than licking them. But many were probably mailed in before it was clear how big a virus risk there was in the state…

Washington’s voting challenges would pale in comparison with those facing the nation if the virus continues to spread, and particularly if it is still a public health risk in November.