While questioning the usefulness of masks he was against lockdowns and promoted the idea of herd immunity.
The 65-year-old the Stanford University neuroradiologist resigned on Monday at the end of his 130-day temporary assignment, according to US media reports.
Atlas tweeted a photo of his resignation letter on Monday. In the letter, he said his “advice was always focused on minimising all the harms from both the pandemic and the structural policies themselves, especially to the working class and the poor.”
“I sincerely wish the new team all the best as they guide the nation through these trying, polarised times,” he wrote, apparently referring to President-elect Joe Biden‘s incoming coronavirus team.
President Trump, a Republican, has not yet conceded to Biden after the Democrat won the November 3 presidential election.
Atlas’ stint in the White House was marked by controversy as he became a close adviser to Trump on the pandemic, adopting public stances on the virus much closer to the President’s.
In one extraordinary episode in October, Twitter removed a tweet from Atlas that sought to undermine the importance of face masks because it was in violation of the platform’s COVID-19 Misleading Information Policy, according to a spokesman for the social media giant.
America’s top public health experts like Dr Anthony Fauci and the Centers for Disease Control and Prevention had accused Atlas of giving President Trump false and misleading information about the spread of the virus.
President-elect Biden has taken a markedly different stance to his predecessor, urging Americans to wear masks and pledging a “bedrock of science” to his policy on tackling the pandemic.
The US is the worst-hit country and has reported more than 13,541,000 confirmed cases and over 268,000 deaths, according to statistics from Johns Hopkins University.