• In August, the CDC revised its Covid-19 testing guidance to say that people who don't have symptoms "do not necessarily need a test" even if they were exposed to an infected person.
• The move was widely criticized by public health specialists and politicians, who said testing symptomless people is an important part of identifying and cutting off chains of spread.
• A House committee on Monday released newly obtained emails that indicate political pressure shaped the guidance.

The Trump administration sought to suppress Covid-19 testing in the United States last year by softening guidance from the Centers for Disease Control and Prevention on who needed to be tested, a House panel said Monday.

In August, the CDC revised its Covid-19 testing guidance to say that people who don't have symptoms "do not necessarily need a test" even if they were exposed to an infected person. The move was widely criticized by public health specialists and politicians, who said testing asymptomatic people is an important part of identifying and cutting off chains of spread.

Assistant Secretary for Health Adm. Brett Giroir, who led the Trump administration's testing effort, at the time firmly denied allegations the White House was pressuring health officials to change the guidance.

But the House Select Subcommittee on the Coronavirus Crisis on Monday released newly obtained emails from a political appointee within the Department of Health and Human Services that indicate he pushed for the new guidance.

In the emails, former HHS scientific advisor Paul Alexander defended the change in testing policy and downplayed the importance of testing people without symptoms, saying it "is not the point of testing." Alexander was brought into HHS by Michael Caputo, a longtime Trump ally who led the department's communications last year before departing abruptly after he accused CDC scientists of sedition.

"Testing asymptomatic people to seek asymptomatic cases is not the point of testing, for in the end, all this accomplishes is we end up quarantining asymptomatic, low risk people and preventing the workforce from working," Alexander wrote one day after the change in CDC testing guidance was reported in an email to other HHS officials.

"In this light, it would be unreasonable based on the prevailing data to have widespread testing of schools and colleges/universities. This will not allow them to optimally re-open," he added, defending the policy change.

In September, the CDC quietly reversed the guidance, saying that anyone, even those without symptoms, who has been in close contact with an infected person needs a Covid-19 test.

Rep. James Clyburn, D-S.C., chairman of the committee that's been investigating allegations of political influence in the nation's top health agencies under the Trump administration, said in letters viewed by CNBC to White House chief of staff Ron Klain and HHS Acting Secretary Norris Cochran that the emails are fresh evidence of political interference at the CDC under Trump.

The email, Clyburn said in the letters, "shows that political appointees were involved in the decision to change CDC's guidance, and that the Trump Administration changed the guidance for the explicit purpose of reducing testing and allowing the virus to spread while quickly reopening the economy."

Clyburn added that the committee has requested more documents from the CDC and other agencies "to understand the full scope and impact of efforts by the Trump White House to suppress coronavirus testing."

Alexander is at the center of the ongoing investigation into whether the administration of President Donald Trump or his appointees allowed politics to shape the nation's response to the pandemic. In December, Clyburn released a trove of emails from Alexander and Caputo that showed "a pernicious pattern of political interference by Administration officials," according to Clyburn.