• The U.S. has reported an average of about 62,210 new cases per day over the past seven days, more than triple the average just a month ago. 
  • Texas, California and Florida accounted for a total of 31,847 new cases on Tuesday, nearly half of all new cases reported across the country. 
  • With new cases surging, especially in so-called hot-spot states across the South and West, the country's testing infrastructure is struggling to keep up.

The United States reported 67,417 new cases of the coronavirus on Tuesday, setting yet another fresh record for new cases reported in a single day, according to data collected by Johns Hopkins University. 

Cases in the U.S. keep climbing, averaging about 62,210 new cases per day over the past seven days — more than triple the number just a month ago and up more than 21% compared with the seven-day average a week ago, according to a CNBC analysis of the data from Hopkins. 

Texas, California and Florida accounted for 31,847 new cases on Tuesday, nearly half of all new cases reported across the country. 

President Donald Trump on Tuesday again attributed the increase in cases to ramped up testing.

The country  processed 760,282 tests on Tuesday, the second-highest number of tests conducted in a single day, according to data compiled by the Covid Tracking Project, an independent volunteer organization launched by journalists at The Atlantic. The U.S. has processed an average of more than 665,000 tests per day between July 1 and July 12, according to a CNBC analysis the Covid Tracking Project's data. That's up from a daily average of just over 174,000 diagnostic tests processed nationally per day through April, according to CNBC's analysis.

"Think of this, if we didn't do testing, instead of testing over 40 million people, if we did half the testing we would have half the cases," the president said Tuesday evening. "If we did another, you cut that in half, we would have, yet again, half of that. But the headlines are always testing." 

Trump's medical advisors, including Director of the National Institute of Allergy and Infectious Diseases Dr. Anthony Fauci, have said the recent surge in cases is a sign of an expanding outbreak, not the increased testing.

Daily new cases have grown by at least 5% compared with a week ago in 43 states and the District of Columbia, according to CNBC's analysis of Hopkins data. And hospitalizations are up more than 5% compared with a week ago in 30 states. Daily new Covid-19 deaths, which lag behind new cases, have also been steadily rising nationally, driven by a number of states with rapidly expanding outbreaks. 

With new cases surging, especially in so-called hot-spot states across the South and West, the country's testing infrastructure, however, is struggling to keep up. Quest Diagnostics and LabCorp, two of the largest diagnostic labs in the country, said earlier this week that the increased demand for testing is slowing their turnaround time. Quest said results for patients who are not "priority 1" now take more than seven days, which public health specialists say makes the tests almost useless to trace cases and isolate people who've been exposed. 

Quest said in a statement Monday it won't be able to "reduce our turnaround times as long as cases of COVID-19 continue to increase dramatically across much of the United States. This is not just a Quest issue. The surge in COVID-19 cases affects the laboratory industry as a whole."

The Centers for Disease Control and Prevention on Tuesday called on Americans to wear masks to help contain the spread of the virus. Director Dr. Robert Redfield told Dr. Howard Bauchner of the Journal of the American Medical Association in an interview Tuesday the U.S. could get its outbreak under control in one to two months if every American wore a mask. 

"The time is now," Redfield said. "I think if we could get everybody to wear a mask right now I think in four, six, eight weeks we could bring this epidemic under control."

As public health officials urge the public to take action to bring the virus under control, the race toward a vaccine is progressing. Moderna said Tuesday that its potential vaccine to prevent Covid-19 produced a "robust" immune response in all 45 patients in its early stage human trial, according to data published Tuesday evening in the peer-reviewed New England Journal of Medicine.

All 45 patients produced neutralizing antibodies, which scientists believe is important for building immunity and provided more promising data that the vaccine may give some protection against the coronavirus. Moderna's stock rose more than 16% in after-hours trading on the news. 

The company is due to start its phase three trial on July 27, according to a posting published Tuesday on The trial, which will be the most comprehensive test of the potential vaccine yet, will enroll 30,000 participants across 87 locations, according to the website.

The CDC and individual health officials have increasingly been facing pressure from Trump and other members of his administration. During an interview Thursday with Fox News' Sean Hannity, the president said, "Dr. Fauci's a nice man, but he's made a lot of mistakes."

"They've been wrong about a lot of things, including face masks," he said. "Maybe they're wrong, maybe not. A lot of them said don't wear a mask, don't wear a mask. Now they're saying wear a mask. A lot of mistakes were made, a lot of mistakes."

On Wednesday, USA Today published an op-ed by White House trade advisor Peter Navarro that targeted Fauci, saying he's "has been wrong about everything I have interacted with him on."

However, the White House quickly moved to distance Trump from the op-ed, saying that the piece is "the opinion of Peter alone," according to White House spokeswoman Alyssa Farah. She added in a tweet that Trump "values the expertise of the medical professionals advising his Administration."

CNBC's Berkeley Lovelace Jr. and Noah Higgins-Dunn contributed to this report.