(CNN) Former US President Barack Obama announced Sunday that he has tested positive for Covid-19.

“I’ve had a scratchy throat for a couple days, but am feeling fine otherwise,” he said on his official Twitter account. Obama also said that his wife, former first lady Michelle Obama, has tested negative.

“Michelle and I are grateful to be vaccinated and boosted,” the former President said. “It’s a reminder to get vaccinated if you haven’t already, even as cases go down.”