“No testing scheme, no test is perfect. There will always be people who go undetected,” said Dr. David Dowdy, an infectious disease epidemiologist at Johns Hopkins University who has researched and written about herd immunity. “The best way to protect the most vulnerable is to reduce the amount of virus that’s in the population that can get through all of those testing schemes and cause destruction.”
Dr. Atlas’s position has been challenged by medical advisers around him who have backgrounds in infectious disease response, revealing a significant rift in the White House over the right approach. Dr. Deborah L. Birx, the White House’s coronavirus response coordinator, has pushed for aggressive, broad testing even among young and healthy people, often clashing with Dr. Atlas in meetings.
“I would always be happy if we had 100 percent of students tested weekly,” Dr. Birx said on Wednesday in an appearance at Penn State University, “because I think testing changes behavior.”
Dr. Atlas at one point influenced the administration’s efforts to install new Centers for Disease Control and Prevention guidance that said it was not necessary to test people without symptoms of Covid-19 even if they had been exposed to the virus, upsetting Dr. Birx and Dr. Robert R. Redfield, the C.D.C. director.
The administration’s efforts to fund federal and state testing have long been fraught. In July, as administration officials and top Senate Republicans clashed over the contours of their initial $1 trillion proposal, the White House initially balked at providing billions of dollars to fund coronavirus testing and help federal health agencies.
Since the early days of the pandemic, Mr. Romer has argued for a wide-scale testing program, costing as much as $100 billion. He had hoped to persuade Dr. Atlas that if officials could quickly identify and isolate people carrying the virus, they would slow its spread and allow normal economic activity to resume more quickly.
In his email, sent to Dr. Atlas’s personal account, Mr. Romer proposed additional testing and isolation efforts that could allow far more Americans to return to work and shopping, generating economic activity that would be 10 or 100 times larger than the cost of the testing program itself.