The White House chief of staff, Mark Meadows, has tested positive for the novel coronavirus.
This comes in the middle of ongoing US electioneering operations.
Also, another top campaign official, Nick Trainer, has also tested positive.
Meadows last emerged without a mask in the audience on Wednesday when Donald Trump was delivering a speech and seeking to secure victory in the US election.
Meadows spent three nights with Trump at Walter Reed National Medical Center while he was healing from COVID-19.
Similarly, US Vice-President Mike Pence’s chief of staff, and former presidential adviser Kellyanne Conway, were some of the presidential staff who had also tested positive.
The President of Brazil has twice screened for COVID-19 but on both occasions he recovered from the disease.