The government's top public health officials warned that the number of Covid-19 cases is rising across a majority of the country in a rare briefing Wednesday afternoon.
Dr. Jay Butler, deputy director for infectious diseases at the Centers for Disease Control and Prevention, said the agency has noted a "distressing trend" in which coronavirus case numbers are "increasing in nearly 75 percent of the country."
"This past week, we've seen nearly 60,000 cases a day on average, as well as 700 deaths," he said.
Butler, a respected career scientist at the agency, spoke Wednesday at a rare on-camera media briefing at the CDC's headquarters in Atlanta, alongside Dr. Robert Redfield, the CDC's director, and Health and Human Services Secretary Alex Azar.
Much of the increase in cases is centered in the Midwest. States like Illinois, Indiana, Michigan, Minnesota, Nebraska and Wisconsin have recorded rises in Covid-19 case numbers in the last two weeks. Public health officials attribute the spikes, in part, to cooler weather that is forcing people indoors.
"Smaller, more intimate gatherings with family, friends and neighbors may be driving infections," Butler said while acknowledging public pandemic fatigue.
"We get tired of wearing masks, but it continues to be as important as it's ever been," he said.
As of Wednesday afternoon, the U.S. had logged 8.3 million cases of Covid-19 and more than a quarter-million deaths, according to an NBC News database. The death toll may, in fact, be far higher, as recent studies have suggested that many deaths related to Covid-19 have been underreported or misreported.
Redfield said Wednesday that the CDC is considering whether it would be reasonable to cut the time a person exposed to Covid-19 may need to be in quarantine. The current guidance is to quarantine for 14 days.
Redfield said a growing body of data is being looked at using testing during quarantine to shorten the 14-day window to 10 or even seven days.
"We don't want to have people quarantined for 14 days unnecessarily," he said.
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The health officials offered no updated timeline for trials of Covid-19 vaccine candidates, opting instead to continue the message of optimism that a safe and effective vaccine may be available "in a matter of weeks or months," Azar said.
"In the meantime, to bridge to that next phase, we have to take steps that can keep ourselves, our families and our communities safe," Azar said. That includes washing hands, wearing masks and staying physically distant.