Borissov, who met Keith Krach, U.S. undersecretary of state for economic affairs, on Friday has informed the U.S. Embassy in Sofia of the situation, the head of Sofia health inspectorate said.
The government press office said Borissov was able to carry out his duties and was in constant contact with his ministers as the Balkan country grapples with a spike in new coronavirus infections.
Borissov had self-isolated late on Friday after he was informed that a deputy minister who he had been in contact with five days ago had tested positive.
Health authorities lifted Borissov’s quarantine late on Saturday after two negative results from coronavirus tests, but then he tested positive on Sunday.
“Although my quarantine was lifted, since Friday I have postponed all my meetings and planned public appearances for the coming days,” Borissov, 61, said in a posting on his official Facebook account.
“After two PCR tests, as of today I am positive with COVID-19,” he said. “I have a general malaise. For the moment, on the doctors’ discretion, I remain on home treatment.”
It was not immediately clear if he was already receiving a specific treatment.
Health Minister Kostadin Angelov said on Facebook he was self-isolating because he met Borissov on Friday. Energy Minister Temenuzhka Petkova and Transport Minister Rosen Zhelyazkov, who attended the meeting with the U.S. official, said they too were self-isolating.
Bulgarian President Rumen Radev, who attended a forum in Estonia on Oct. 19 along with Polish President Andrzej Duda, tested negative Sunday, he said on Facebook. Duda has tested positive for coronavirus on Saturday.