“They know who is most at risk,” said Kentucky Gov. Andy Beshear, a Democrat, during a Thursday press conference. “There are a limited number that we can include in this very first shipment.”

Some argue that governors are better off deferring decisions on vaccination priorities to providers, given the scarcity of the first doses and limited time to sort out thorny ethical and logistical questions. But others worry the patchwork approach could undermine the effort to transparently and equitably distribute the vaccine.

“It’s pretty chaotic right now,” said Eric Toner, a senior scholar at the Johns Hopkins Center for Health Security. “Bottom line: Things are going to be very messy.”

Kentucky, along with Mississippi and New York, have instructed hospitals to devise tiering systems to determine which employees should receive the first vaccinations. Other states, including Arkansas and Minnesota, are holding off on making decisions until they receive guidance from their own advisory panels.