The White House said neither President Joe Biden nor first lady Jill Biden were considered a “close contact” of Harris in recent days.
The White House said Tuesday that Harris tested positive on both rapid and a PCR tests, adding she “has exhibited no symptoms”.
Harris will isolate at her residence but continue to work remotely, and would only return to the White House once she tests negative for the virus.
Harris, 57, received her first dose of the Moderna Covid-19 vaccine weeks before taking office and a second dose just days after Inauguration Day in 2021. She received a booster shot in late October and an additional booster on April 1.
Fully vaccinated and boosted people have a high degree of protection against serious illness and death from Covid-19, particularly from the most common and highly transmissible omicron variant.