Dr. Robert Redfield, the director of the Centers for Disease Control and Prevention, said during hisbefore a Senate subcommittee on Wednesday that wearing face masks may be more effective at protecting against COVID-19 than a .
Lawmakers asked Redfield and other top health officials about the government's response to the coronavirus pandemic, and he was questioned about the CDC's recommendation that people wear masks — a practice President Trump has often dismissed.
"I'm not going to comment directly about the president, but I am going to comment as the CDC director that face masks, these face masks, are the most important powerful public health tool we have," Redfield said. "And I will continue to appeal for all Americans, all individuals in our country, to embrace these face coverings."
Redfield said if Americans wore face masks for several weeks, "we would bring this pandemic under control," because there is scientific evidence they work and they are our "best defense."
"I might even go so far as to say that this face mask is more guaranteed to protect me against COVID than when I take a COVID vaccine, because it may be 70%. And if I don't get an immune response, the vaccine is not going to protect me," Redfield said. "This face mask will."
Several experts contacted by CBS News agree with that assessment: Since vaccines do not guarantee an immune response, masks may be more effective at preventing COVID-19. The FDA has previously said it would approve a coronavirus vaccine that was. While that could significantly reduce the number of hospitalizations and deaths, it would not completely eliminate the disease or guarantee protection.
George Rutherford, a professor of epidemiology and biostatistics and director of the Prevention and Public Health Group at UC San Francisco, said the CDC director is "completely right."
"The good thing about a vaccine is you don't need to remember to put it on every day," Dr. Rutherford told CBS News on Friday. "The bad thing is, it's probably not going to work nearly as well as masks."
"Let's say masks are 95% effective — and who knows what the vaccine is going to be, but say it's 80% effective — in that sense, masks could be better than vaccines," he continued. "I don't think we know yet, but for right now, it's the total name of the game. It's the most effective thing we have."
Rutherford said a large proportion of the population — about 60 or 70% — would need to get vaccinated in order to achieve something close to herd immunity. "Once you're vaccinated... you're probably pretty safe. Now, if we're still walking around with lots of transmission going on, among people who didn't get vaccinated, you may want to wear a mask as well."
He said that without knowing what the vaccine efficacy will be, it's impossible to answer how protected we will be from the virus. "If it's more like 50% [effective], like the flu vaccine, then we're going to have to get a lot of people vaccinated in order to get to herd immunity," he said.
The efficacy of the vaccine will help determine how long it will take to reach herd immunity — and how long we will need to wear masks for protection, Rutherford said.
After Wednesday's hearing, Redfield took to Twitter to clarify his comments on masks and vaccines. "I 100% believe in the importance of vaccines and the importance in particular of a #COVID19 vaccine," he wrote. "A COVID-19 vaccine is the thing that will get Americans back to normal everyday life."
"The best defense we currently have against this virus are the important mitigation efforts of wearing a mask, washing your hands, social distancing and being careful about crowds," Redfield added in another tweet.
In the early days of the pandemic health officials did not recommend masks, but they did an about-face and startedas the evidence grew that of the contagious respiratory virus.
Severalare in the final stages of testing, and if all goes well the first doses could be rolled out later this year. However, the process of distributing a vaccine to millions of people nationwide .
Dr. Paul Goepfert, professor of medicine and director of the Alabama Vaccine Research Clinic, also raised the point that "we do not know the efficacy of the COVID vaccines yet, nor how quickly available they will be if found to be effective, nor the percent of the population."
"Since we do not know any of that information yet, masks are a better solution," Goepfert told CBS News via email. "However, should a vaccine be shown to be effective, readily available, and widely distributed, it is certain that vaccination would be a much better method of controlling the pandemic just as it has for so many other infectious diseases."