British Prime Minister Boris Johnson went into isolation after a contact tested positive for the coronavirus.

In a statement, No. 10 Downing Street said Johnson wasn’t experiencing symptoms but would follow guidance from Britain’s National Health Service, which recommends self-isolation after prolonged exposure to someone who has the virus.

“He will carry on working from Downing Street,” a spokesman said, adding that the prime minister, who spent three nights in intensive care during his April bout of Covid-19, did not have any symptoms.

Global infections have soared past 54 million with more than 1.3 million deaths, and the spikes have forced governments to reimpose restrictions on movement and gatherings.

Two weeks ago, Johnson announced new lockdown measures after a sharp rise in case numbers in the U.K. during October. As of Saturday, the country had recorded 1.3 million cases and more than 51,000 deaths since the pandemic began.