Coronavirus: British Prime Minister Boris Johnson contracts COVID-19

British Prime Minister Boris Johnson has contracted coronavirus COVID-19.

In a two-minute Facebook video, Johnson revealed he had developed mild symptoms of the respiratory illness, which has infected nearly 550,000 people worldwide and killed just under 25,000. He said those symptoms were a temperature and a persistent cough.

He was tested and the results came back positive. Johnson said he is now self-isolating and working from home.

"Be in no doubt, I can continue, thanks to the wizardry of modern technology, to communicate with all of my top team, to lead the national fight back against coronavirus," he said,

Johnson thanked officials, only hours after joining in a national acknowledgment of health staff by standing outside Downing St and clapping.

Australian Prime Minister Scott Morrison has sent his warm wishes.

"Thinking of you and all our UK friends as we work together to get through this."

There are more than 11,500 cases of coronavirus COVID-19 in the United Kingdom. Several MPs have contracted the virus. Earlier this week, the country went into a state of lockdown, with people asked to stay at home. The only exceptions will be for shopping for basic necessities, one form of exercise a day, any medical needs, or to go to and from work if absolutely necessary.

All non-essential businesses will close, gatherings of more than two people are now banned and all events stopped, excluding funerals. Parks will remain open, but police will break up any gatherings.

In announcing the measures, Johnson called coronavirus "the biggest threat this country has faced in decades" and said without intense rules, more people would lose their lives.

"No Prime Minister wants to enact measures like this. I know the damage that this disruption is doing and will do to people's lives, to their businesses, to their jobs," he said.

Johnson is among the most high-profile people in the world to contract the illness. Earlier this week, Prince Charles revealed he had the disease.