WASHINGTON (NEXSTAR) – Iowa Sen. Chuck Grassley announced Tuesday afternoon that he has tested positive for coronavirus, hours after releasing a statement saying that he had been exposed to the virus.

Grassley, who is 87 years old and the longest-serving Republican senator, did not say how he was exposed.

“I’ll b following my doctors’ orders/CDC guidelines & continue to quarantine,” the GOP senator tweeted. “I’m feeling good + will keep up on my work for the ppl of Iowa from home. I appreciate everyone’s well wishes + prayers &look fwd to resuming my normal schedule soon.”

The Iowa Republican is the president pro tempore of the Senate, meaning he presides over the Senate in the absence of Vice President Mike Pence and is third in the line of presidential succession, behind Pence and House Speaker Nancy Pelosi. The president pro tempore is the senator in the majority party who has served the longest.

By missing votes this week, Grassley will break a 27-year streak of not missing a single Senate vote. According to his office, the last time he missed a vote was in 1993, when he was in Iowa assisting with relief efforts after severe flooding.

Grassley was first elected to the U.S. House in 1974 and then to the Senate in 1980. He is the chairman of the Senate Finance Committee and is expected to become the top Republican on the Senate Judiciary Committee when a new Senate session begins in January.

The Associated Press contributed to this report.