Four former heads of the US Centers for Disease Control and Prevention (CDC) criticized the Trump administration Tuesday saying it is undermining the federal health agency and taking "political potshots" at scientists during the COVID-19 pandemic.

In related news, Senator Lindsay Graham, a supporter of President Donald Trump, gave his support on Tuesday to Dr Anthony Fauci, the nation's top infectious diseases expert, saying that any effort by the White House to undermine Fauci would be unproductive as novel coronavirus cases surge across the country.

The four ex-CDC directors wrote in an op-ed in The Washington Post:

"As America begins the formidable task of getting our kids back to school and all of us back to work safely amid a pandemic that is only getting worse, public health experts face two opponents: covid-19, but also political leaders and others attempting to undermine the Centers for Disease Control and Prevention.

"Trying to fight this pandemic while subverting scientific expertise is like fighting blindfolded," they wrote. "How well and how quickly we adhere to the advice of public health experts at the CDC will determine whether, how soon and how safely our schools can reopen. It is not too late to give the CDC its proper role in guiding this response. But the clock is ticking."

The piece was written by Tom Frieden, Jeffrey Koplan and David Satcher, all former CDC directors, as well as former acting CDC director Richard Besser. They criticized administration officials for taking "political potshots" at scientists during the pandemic.

Frieden served as CDC director from 2009 to 2017 under President Barack Obama. Koplan served as director from 1998 to 2002 under Bill Clinton and George W. Bush. Satcher served as director from 1993 to 1998 under Clinton. Besser served as acting director in 2009 during the Obama administration.

The former CDC chiefs also warned that opening schools too early and without adequate precautions in place could further the spread of the virus.

Graham, when asked about reports of the Trump administration trying to discredit Fauci, said:

"Has he been right all the time? No. We don't have a Dr Fauci problem. We need to be focusing on doing things that get us where we need to go. So, I have all the respect in the world for Dr Fauci. I think any effort to undermine him is not going to be productive, quite frankly."

Graham also called Fauci one of the "smartest people" he knows.

"Getting in a contest with Dr Fauci about whether he was right or wrong doesn't move the ball forward," said Graham, "because here's where we are as a nation: The infection rate is going up, we shut the whole country down. It's time to reopen up smartly. It's time to go back to school, and we're going to deal with the reality that we're not as prepared as we need to be, but we are moving in the right direction."

White House officials, including President Trump, have openly criticized Fauci over his public health advice during the pandemic.

Last week, in an interview with Sean Hannity on Fox News, Trump said Fauci "has made a lot of mistakes".

On Monday, Trump told reporters: "I have a very good relationship with Dr Fauci. I've had for a long time, right from the beginning. I find him to be a very nice person. I don't always agree with him."

Also Monday, Dan Scavino, the White House director of social media, posted a cartoon on Facebook portraying Fauci as a faucet, flushing the US economy down the drain.

"Sorry, Dr. Faucet!" Scavino wrote. "At least you know if I'm going to disagree with a colleague, such as yourself, it's done publicly and not cowardly, behind journalists with leaks."

The US Public Health Service's Admiral Brett Giroir, the administration's testing czar, told NBC's Meet the Press on Sunday that he respects Fauci but he is not "100 percent right".

White House trade adviser Peter Navarro told CBS News over the weekend, "Dr Fauci has a good bedside manner with the public but he has been wrong about everything I have ever interacted with him on."