Coronavirus has killed over 100,000 people in the US

Understanding the massive scale of coronavirus in the US

Six feet of distance may not be enough, experts warn

Health officials have struggled to make sense of the highly contagious and poorly understood disease even as coronavirus circulates in the United States, where nearly 1.7 million have tested positive.

Robert Schooley of the University of California, San Diego.

"Increasing evidence for [the coronavirus] suggests the six-foot WHO recommendation is likely not enough under many indoor conditions where aerosols can remain airborne for hours, accumulate over time and follow air flows over distances farther than six feet," they wrote.

The three experts are specialists in chemistry and infectious diseases.

While health officials have focused on droplets, the three experts said "a large proportion" of the spread of coronavirus disease appears to be occurring through airborne transmission of aerosols produced by asymptomatic people during breathing and speaking.

Change of behavior is more crucial than a vaccine

The US did not have to lose 100,0000 people in the first five months of the coronavirus pandemic, according to an expert on viruses and biotechnology.

"It didn't have to happen if we had been prepared."

Experts had worked with the US Department of Defense and Homeland Security to plan and protect the country from bioterrorism, as well as from threats like the coronavirus.

"It was totally predictable that another coronavirus was on its way," Haseltine said.

"There was a hole in our safety net."

China, New Zealand, and Australia have effectively dealt with coronavirus outbreaks, bringing their cases down through testing, contact tracing and isolation, Haseltine said.

Washington, DC will move Friday into Phase 1 of reopening after it had a 14-day decline in cases of coronavirus community spread, , Mayor Muriel Bowser said.