If Reed Exhibitions stages a Book Expo and Book Con in late July, it will happen without any of the country’s five largest trade publishers. On Thursday, Macmillan joined the others in announcing that it, too, will not participate: “Due to an abundance of caution for our employee safety and guidance of the city and state, Macmillan Publishers has made the difficult decision to withdraw from BookExpo and BookCon 2020. While we are disappointed with the situation we are in, we promise to find other opportunities to interact with our booksellers, librarians, readers, and fans going forward.”