WASHINGTON (AP) — Iowa Sen. Chuck Grassley, the longest-serving Republican senator, says he is quarantining after being exposed to the coronavirus.

Grassley, 87, did not say how he was exposed. He said he would follow doctor’s orders and “immediately quarantine” and work virtually as he waits for results of a test.

“I’m feeling well and not currently experiencing any symptoms, but it’s important we all follow public health guidelines to keep each other healthy,” Grassley said in a statement.

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.