'More cases, more rapidly': Birx, Fauci warn Americans to buckle down as COVID-19 cases surge

 During the first White House Coronavirus Task Force briefing held in months, public health officials on Thursday pleaded with Americans to “double down” on efforts to prevent the spread of COVID-19 and said cases are spreading “more rapidly” than ever. 

Dr. Deborah Birx urged Americans “to increase their vigilance” while standing in front of a chart showing a rise in the test positivity rate, indicating increased community spread in states across the U.S. 

The positivity rate — the percentage of tests coming back positive for COVID-19 — has soared to record levels all around the nation. South Dakota, Iowa and Wyoming’s rate are all averaging above 50%, and the national average is now 10%.

Birx said people are "unknowingly spreading the virus to others," and called on Americans to wear a mask while donning her own.

“This is more cases, more rapidly, than what we had seen before,” she said.

The nation’s top infectious disease expert, Dr. Anthony Fauci, touted the safety of the vaccine development process, which is nearing the finish line, but said the country needs to continue public health measures in the meantime.

"I've used that metaphor that the cavalry is on the way. If you're fighting a battle and the cavalry is on the on the way, you don't stop shooting, you keep going until the cavalry gets here," Fauci said. "And then you might even want to continue fighting."

Fauci echoed that Americans should wear face coverings and maintain social distancing as they await a vaccine.

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The briefing marked the first time members of the task force have held one since July. Vice President Mike Pence, who is head of the task force, noted that cases and hospitalizations are rising. President Donald Trump did not attend the briefing.

The United States has seen more than 11 million diagnosed infections and over 250,000 deaths from the coronavirus, according to data from Johns Hopkins University. CDC scientists believe that somewhere around 40% of people who are infected do not have obvious symptoms but can still spread the virus.

Health experts have forecasted a particularly morbid winter due to a disregard for mask-wearing and other precautions. 

With the onset of cold weather and crowded holiday gatherings quickly approaching, health officials say that small household gatherings have become an important contributor to the rise in COVID-19 cases.

Earlier Thursday, the CDC urged Americans not to travel for Thanksgiving and not to spend the holiday with people from outside their household.

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This story was reported from Cincinnati.