The Centers for Disease Control and Prevention is warning that as many as 25 percent of people infected with the novel coronavirus (COVID-19) may be asymptomatic, meaning they may never show any symptoms. Based on this information, the federal health agency is considering advising all Americans to wear masks, in a reversal of their previous stance.
“One of the [pieces of] information that we have pretty much confirmed now is that a significant number of individuals that are infected actually remain asymptomatic,” CDC director Dr. Robert Redfield told NPR on Tuesday.
“That may be as many as 25 percent. That’s important, because now you have individuals that may not have any symptoms that can contribute to transmission, and we have learned that in fact they do contribute to transmission,” he added.
According to Redfield, COVID-19 has the ability to transmit far easier than flu, and it is “probably now about three times as infectious as the flu.”
Michael Brochstein / Echoes Wire/Barcroft Media via Getty Images Dr. Robert Redfield
Redfield also revealed that the CDC has learned that those who do show symptoms are usually already contagious up to 48 hours before the symptoms appear — meaning they could be transmitting the symptoms for days before realizing they have it.
“This helps explain how rapidly this virus continues to spread across the country,” he told NPR. “Because we have asymptomatic transmitters and we have individuals who are transmitting 48 hours before they become symptomatic.”
As of Wednesday morning, April 1, at least 189,000 people across U.S. have tested positive for the virus and at least 3,900 patients with the virus have died, according to a New York Times database. Each day, the number of cases across the country escalate by the thousands.
Ben Hasty/MediaNews Group/Reading Eagle via Getty Images
Given the new data on asymptomatic carriers and transmission, Redfield said that the CDC is now reviewing their guidelines on face masks — after repeatedly saying that the general public does not need to wear masks unless they are feeling sick.
“Particularly with the new data, that there’s significant asymptomatic transmission, this is being critically re-reviewed to see if there’s potential additional value for individuals that are infected or individuals that may be asymptomatically infected [to wear face mask],” he said. “I can tell you that the data and this issue of whether it’s going to contribute [to prevention] is being aggressively reviewed as we speak.”
Dr. Anthony Fauci, who is a part of President Donald Trump’s coronavirus task force and the nation’s top infectious disease expert, echoed Redfield while speaking to CNN on Tuesday.
“The idea of getting a much more broad community-wide use of masks outside of the health care setting is under very active discussion at the Task Force,” he said. “The CDC group is looking at that very carefully.”
Gary Hershorn/Getty Images
Fauci added that their main concern with a policy like that is making sure they are not taking supplies away from health care workers, who have repeatedly expressed a shortage in personal protective equipment across hospitals and medical facilities in the U.S.
“But when we get in a situation where we have enough masks, I believe there will be some very serious consideration about more broadening this recommendation of using masks,” he added. “We’re not there yet, but I think we’re close to coming to some determination.”
In the meantime, Redfield reminds Americans that their most “powerful weapon” against contracting the virus and spreading it is to continue social distancing.
“This virus cannot go from person to person that easily. It needs us to be close. It needs us to be within 6 feet. If we just distance ourselves, this virus can’t sustain itself and it will go out,” he said. “So this social distancing that we’re pushing, is a powerful weapon, and that will shut this outbreak down sooner than it otherwise would have been shut down.”
“I’d like to thank all the Americans and all the people in our nation that have taken this to heart and really practice aggressive social distancing,” he added.
Redfield and the CDC predict for now that the U.S. should see a decline in the virus late spring and early summer, but warns this will be a seasonal occurrence with a second wave expected to hit in the fall and winter.
“As next season comes up, it’s going to be important that we reembrace that social distancing,” Redfield said.
As information about the coronavirus pandemic rapidly changes, PEOPLE is committed to providing the most recent data in our coverage. Some of the information in this story may have changed after publication. For the latest on COVID-19, readers are encouraged to use online resources from CDC, WHO, and local public health departments. To help provide doctors and nurses on the front lines with life-saving medical resources, donate to Direct Relief here.