Dr. Deborah Birx, the White House coronavirus task force coordinator, said the timeliness of data reported from China to the World Health Organization "did delay the ability" to declare the coronavirus a global pandemic. Birx also thanked workers on the front lines of the pandemic and expressed hope that large-scale mitigation efforts are working to flatten the virus curve.

President Trump criticized the World Health Organization in a Tuesday task force briefing. He blamed the agency for not providing better warnings ahead of the pandemic, thereby allowing it to spread as quickly as it did.

"The WHO can only react to the data it's given, and when you go back and look at the timeline, it wasn't until, I think, almost the middle of January that China reported that there was human-to-human transmission," Birx said.

She said there was a need to "investigate reporting and how reports were received there," which led to a delay in WHO's warnings to the rest of the world.

Birx added that investigations can wait until after the outbreaks are mitigated, and that the knowledge gained will help the global community through future pandemics.

During the same Tuesday press conference, the nation's infectious disease expert, Dr. Anthony Fauci, said he thought the U.S. could return to some semblance of normal life as early as the fall. Birx credited both national and global efforts for the "early chutes of success in mitigation in the larger metro areas" that are beginning to give experts insights into an end to the global threat.

"We're learning every day how to do it, how to do it better, what can be done, what needs to be done," Birx said. "I think we're really better prepared both for analyzing what's happening now and what's going to happen in the future."