Feinstein, 89, had not previously disclosed those medical details, though she said in a statement last week that she had suffered complications from the virus. The longtime California senator returned from a more than two-month absence on May 10 after weeks of questions about her declining health and whether she would be back in the Senate at all.

Adam Russell, a spokesman for Feinstein, said that the encephalitis, or inflammation of the brain, “resolved itself shortly after she was released from the hospital in March.” Feinstein continues to have complications from the Ramsay Hunt syndrome, Russell said.

Russell confirmed the two complications after the New York Times first reported them, raising questions about whether she had been hiding the extent of her illnesses. Upon her return last week, Feinstein was using a wheelchair and noticeably thinner, and has appeared confused at times when speaking to reporters or being wheeled through the halls.

“The senator previously disclosed that she had several complications related to her shingles diagnosis,” Russell said in the statement. “As discussed in the New York Times article, those complications included Ramsay Hunt syndrome and encephalitis.”

Feinstein’s face has appeared partially paralyzed since she returned to the Senate, stirring some speculation about whether she had had a stroke. Ramsay Hunt syndrome is a complication that occurs when the shingles virus reaches a facial nerve near the ears. It can also cause hearing loss.

Encephalitis can also be caused by shingles. The swelling of the brain can have a number of different symptoms, including personality changes, seizures, stiffness, confusion and problems with sight or hearing, according to the Mayo Clinic.

Aides to Feinstein said last week that she is still recovering from her illness and would operate on a reduced schedule. Since she has returned, she has missed some votes where she was not needed. On Wednesday, for example, she missed the first three Senate votes of the day but appeared for the last two, in which the margin was much closer.

Feinstein has faced questions for several years about her clearly declining health and her mental acuity. In February Feinstein said she would not run for re-election in 2024.

But some Democrats have pushed for her to leave sooner. A member of the California congressional delegation, Democratic Rep. Ro Khanna, called on her to resign as she stayed away from Washington for more than ten weeks, and several other House progressives have echoed his call. And Senate Democrats were increasingly anxious during Feinstein’s absence as they were unable to confirm some of President Joe Biden’s judicial nominees with a narrow 51-49 majority.

As Democrats worried, Feinstein made an unusual request to be temporarily replaced on the Judiciary panel while she remained out of the Senate. But Republicans last month blocked a vote, saying there was little precedent for a temporary committee replacement and that they didn’t want to help Democrats confirm the most partisan judges. Others said they thought Democrats were unfairly trying to push her out of office.

Two weeks later, Democrats said that Feinstein would return to Washington.

A senator for more than three decades, Feinstein has had a groundbreaking political career and shattered gender barriers. She was the first woman to serve as president of the San Francisco Board of Supervisors in the 1970s and the first female mayor of San Francisco. She ascended to that post after the November 1978 assassinations of then-Mayor George Moscone and City Supervisor Harvey Milk by a former supervisor, Dan White. Feinstein found Milk’s body.

In the Senate, she was the first woman to head the Senate Intelligence Committee and the first woman to serve as the Judiciary Committee’s top Democrat.