England's Chief Medical Officer Professor Chris Whitty Alberto Pizzoli/AFP/Getty Images

England's Chief Medical Officer Professor Chris Whitty has coronavirus symptoms and is self-isolating at home, he tweeted on Friday.

"After experiencing symptoms compatible with COVID-19 last night, in line with the guidance, I will be self-isolating at home for the next seven days. I will be continuing to advise the Government on the medical response to Coronavirus, supported by my deputies," Whitty tweeted.

The news comes just hours after the UK's Prime Minister Boris Johnson and Health Secretary Matt Hancock announced they had also tested positive for the coronavirus.

With three of the key people in charge of the UK's response to the pandemic now infected by the virus, it raises the question of how many more people at the top of the British government have been affected.

Johnson had been criticized for continuing to shake people's hands in public while government advice was to keep around two meters away from other people. The Prime Minister, Whitty and Chief Scientific Adviser Patrick Vallance had also been giving regular in-person news conferences to journalists until Tuesday.

Neil Ferguson, a top UK government adviser on the virus, said he believed he had been infected just over a week ago, warning: "There is a lot of Covid-19 in Westminster."

Prince Charles, the heir to the British throne, also tested positive for coronavirus this week.