Scaramella was exposed to a much lower level of radioactive substance than Litvinenko, doctors treating him said.
London's University College Hospital confirmed Scaramella had been hospitalized after tests confirmed he had been exposed to polonium-210, the rare substance found in Litvinenko's body before he died Nov. 23. Scaramella had shown "no symptoms of radiation poisoning," hospital spokesman Keith Paterson said.
Scaramella had met with Litvinenko at the Itsu sushi restaurant on Nov. 1, the day the ex-Russian spy believed he was given the poison that eventually killed him. Scaramella is under treatment at the same hospital Litvinenko was treated at, CBS News correspondent Richard Roth reports.
Litvinenko's wife, Marina, showed no ill effects after she was confirmed as having shown traces of the same substance, the ex-spy's friend Alex Goldfarb said Friday.
"She is very slightly contaminated," Goldfarb told The Associated Press. "There are no dangerous levels, no treatment, no hospitalization."
Meanwhile, in East Sussex, in southern England, police and health officials evacuated and later reopened the Ashdown Park Hotel and Country Club — where Scaramella had been staying — after testing for signs of the substance. No test results were released.
"Police said they found nothing of any concern," said Graeme Bateman, the managing director of the hotel.
Home Secretary John Reid said one adult — a Litvinenko family member — had tested positive for signs of polonium-210, the rare substance found in the former spy's body. He did not elaborate.
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The member of Litvinenko's family who had tested positive had been exposed to a "very small" long-term health risk, government health agency chief Pat Troop said.
"It is important to remember that Mr. Litvinenko's family experienced the closest contact with him during his illness and despite these results the level of exposure, this adult family member received is a tiny fraction of the lethal dose received by Mr. Litvinenko himself," Troop said.
Troop also declined to identify the family member.
Litvinenko's wife and his father, Walter, kept a vigil at his hospital bedside before he died.
Scaramella was admitted to University College Hospital surrounded by police, who are holding him in protective custody.
Over lunch at the sushi restaurant on Nov. 1, Scaramella told Litvinenko about an e-mail he received from a source naming the killers of investigative journalist Anna Politkovskaya, who was gunned down on Oct. 7 at her Moscow apartment building. The e-mail reportedly said that he and Litvinenko — a friend of the reporter — were also on the hit list.
Three pathologists, meanwhile, completed Litvinenko's autopsy at the Royal London Hospital's forensic science facility Friday, coroner Dr. Andrew Reid said.
Wearing protective suits — with space suit-style helmets — one pathologist was representing the government, a second acted on behalf of Litvinenko's wife, while the third was an independent specialist attending in case a criminal prosecution takes place. When the autopsy is complete, Litvinenko's body will be sealed in a special coffin before it is buried to keep the radiation from spreading, Roth reports.
Results of the autopsy may not be available for several days while tests are carried out, police said.