Top infectious diseases expert Anthony Fauci is among three members of the White House's coronavirus task force who will self-isolate after potential exposure to the pathogen, US media reported.
On Friday, reports that Vice President Mike Pence's press secretary had tested positive heightened fears about senior administration officials catching the virus.
Robert Redfield, the director of the Centers for Disease Control and Prevention, and Stephen Hahn, the commissioner of the Food and Drug Administration, will self-isolate, CNN said.
But Fauci -- who has become the trusted face of the government's virus response -- told the network he would undergo a "modified quarantine" because he had not been in close proximity to the contagious White House staffer.
The head of infectious diseases at the National Institutes of Health will remain at home teleworking and will wear a mask for two weeks.
He is also undergoing daily coronavirus tests, and has so far been negative for the disease.
Redfield and Hahn will quarantine for two weeks after exposure to a person who tested positive, FDA and CDC statements to US media said.
Officials have not revealed the identity of the COVID-19 positive individual in contact with the task force.
Earlier in the week US President Donald Trump announced plans to shut down the highly visible task force, only to backtrack one day later.
Members of the group -- which coordinates between medical institutes, political staff and state governors -- gave daily press conferences meant to inform the nation on the latest status of the pandemic.
But they were often overtaken by Trump's own freewheeling question-and-answer sessions, and the press conferences ended roughly two weeks ago.
All three men will still testify at Tuesday's Senate coronavirus hearing, with Redfield and Hahn dialing in via videoconferencing software, according to Senator Lamar Alexander, chairman of the chamber's health committee.
It is believed Fauci will attend wearing a mask, CNN reported.
The US has recorded more than 78,000 fatalities and 1.3 million infections.