@Don3153 Your listing appears to be an Entire Home property. Is this guest booked with a delisted Private Room?
You can see whether you're eligible for a penalty-free cancellation here: https://www.airbnb.com/help/article/2701/coronavirus-information-and-extenuating-circumstances-polic...
Even if you're not eligible now, the situation will evolve rapidly between now and April so you can expect the rules to change a lot. Unless your booked guest is coming from China, Italy, or South Korea I would recommend holding off for another week or so. But perhaps if you communicate with your guest, you'll find that they might also be reconsidering their plans and wanting to cancel, which would let you off the hook.