British Prime Minister Boris Johnson has been admitted to hospital for tests after showing persistent symptoms of Coronavirus 10 days after testing positive for it.

Johnson’s office said he was hospitalized because he still has symptoms 10 days after testing positive for the virus.

“On the advice of his doctor, the Prime Minister has tonight been admitted to hospital for tests,” Downing Street said on Sunday.

“This is a precautionary step, as the Prime Minister continues to have persistent symptoms of coronavirus 10 days after testing positive for the virus.”

Johnson, 55, has been quarantined in his Downing Street residence since being diagnosed with COVID-19 on March 26.

He went into isolation in a flat in the building and said on Friday that he was staying there as he still had a high temperature.

Johnson has continued to chair daily meetings on the UK’s response to the outbreak and has released several video messages during his 10 days in isolation.

He had  received medical advice by phone during his illness but going to an hospital means doctors can see him in person.

The government said Sunday that almost 48,000 people have been confirmed to have COVID-19 in the U.K. and that 4,934 of them have died.