U.S. Senator Dianne Feinstein, 89, Hospitalized with Shingles

Ranking member U.S. Sen. Dianne Feinstein (D-CA) questions Supreme Court nominee Judge Amy Coney Barrett as she testifies before the Senate Judiciary Committee on the second day of her Supreme Court confirmation hearing on Capitol Hill
Ranking member U.S. Sen. Dianne Feinstein (D-CA) questions Supreme Court nominee Judge Amy Coney Barrett as she testifies before the Senate Judiciary Committee on the second day of her Supreme Court confirmation hearing on Capitol Hill

Kevin Dietsch-Pool/Getty Dianne Feinstein

United States Sen. Dianne Feinstein has been admitted to a San Francisco hospital to be treated for shingles, according to a statement from her office.

The California Democrat, who is a six-term senator and the oldest member of Congress at age 89, reported she was diagnosed with the condition last month and is expected to make a full recovery.

"I was diagnosed over the February recess with a case of shingles," Feinstein said in her statement. "I have been hospitalized and am receiving treatment in San Francisco and expect to make a full recovery. I hope to return to the Senate later this month."

According to the Centers for Disease Control and Prevention, shingles are a virus that causes a painful rash that consists of blisters that scab over after seven to 10 days. It can result in long-term nerve pain, the risk of which increases with age.

RELATED: Sen. Dianne Feinstein Responds After Colleagues' Accounts That Her Memory Is Deteriorating

The announcement of Feinstein's illness comes just two weeks after she announced she would retire at the end of her term next year.

"I am announcing today I will not run for reelection in 2024 but intend to accomplish as much for California as I can through the end of next year when my term ends," she said in a statement issued on Feb. 14.

A report published by The San Francisco Chronicle in April of 2022 cited four U.S. senators, including three Democrats; three former staffers; and a Democratic House member from California, who said Feinstein's memory was deteriorating to the point that they felt she could not fulfill her job duties without the help of her staff.

RELATED: John Fetterman Overcame a Stroke on the Campaign Trail to Win a Senate Seat: 'I Almost Died'

In a statement to PEOPLE shared by her press team at the time, Feinstein — who has been in office since 1992 — spoke out against the accounts on her mental health after they first surfaced.

"I remain committed to do what I said I would when I was re-elected in 2018: fight for Californians, especially on the economy and the key issues for California of water and fire," she said.

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Feinstein is one of two Senate Democrats currently out with illness. Sen. John Fetterman (D-Pa.), 53, still recovering from a stroke last year, checked himself into the hospital two weeks ago for clinical depression.