While officials try to adapt to the rise of the omicron variant, former Centers for Disease Control and Prevention Director Robert Redfield said on Wednesday that the nature of the coronavirus is going to keep changing.

"Clearly the nature of this virus is, it will keep changing and have new variants. Those variants are going to be important in that they will gain transmission advantage," Redfield told "America’s Newsroom" co-host Dana Perino. 


Redfield noted the long lines for COVID testing seen outside locations in New York City and other places.

"The nation needs at least a billion tests a month to meet the need," he said, adding that students should be regularly tested at school, but the testing capacity still does not exist. 

President Biden answers questions after speaking about the status of the country's fight against COVID-19 and the Omicron variant, in the State Dining Room of the White House in Washington, on Dec. 21, 2021.  (Photo by BRENDAN SMIALOWSKI/AFP via Getty Images) (BRENDAN SMIALOWSKI/AFP via Getty Images)

The omicron variant of the coronavirus now accounts for nearly three-quarters of all new infections in the U.S., according to the latest data from the Centers for Disease Control and Prevention. 

Estimates for the week ending Dec. 18 indicate that omicron is behind 73.2% of total new cases, compared to 26.6% for the Delta variant, the data shows

In the week before, only 12.6% of positive tests were a result of the omicron variant, as Delta, at 87%, remained the most infectious variant in the U.S., according to the CDC.  

FILE - Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, speaks during the daily briefing at the White House in Washington, Wednesday, Dec. 1, 2021. U.S. health officials said Sunday, Dec. 5 that while the omicron variant of the coronavirus is rapidly spreading throughout the country, early indications suggest it may be less dangerous than delta, which continues to drive a surge of hospitalizations. President Joe Biden's chief medial adviser, Dr. Anthony Fauci, told CNN's "State of the Union" that scientists need more information before drawing conclusion's about omicron's severity. (AP Photo/Susan Walsh, File) 

Redfield said five months ago he predicted that a new variant would be more transmissible than the delta variant. 

"I will say in the next six months we should anticipate another variant more transmissible than omicron," Redfield said, adding that it's the nature of viruses. 


"The virus will continue to evolve and seek a transmission advantage. That transmission advantage now in a population that’s largely been infected in the past or vaccinated will be a transmission advantage in people that have some evidence of immunity from infection or vaccine and that’s what we’re seeing, unfortunately."

Fox News' Greg Norman contributed to this report.