Robert Redfield says masks, washing hands and social distancing are key.

Robert Redfield, director of the Centers for Disease Control and Prevention, believes “the most powerful weapon we have” against the novel coronavirus is wearing face coverings, washing hands and “being smart about social distancing.”

“If we all rigorously did this, we could really bring this outbreak back to where it needs to be,” Redfield told the Journal of the American Medical Association via video on Tuesday.

Coronavirus cases are surging across the U.S., from California to Texas to Florida. More than 3.4 million people in the country have been diagnosed with the coronavirus and over 136,00 people have died.

To Redfield, a major key to controlling the pandemic is wearing masks.

“I really do believe if the American public all embraced masking now and we really did it, you know, rigorously … I think if we can get everybody to wear a mask right now, I really do think over the next four to six, eight weeks, we can bring this epidemic under control,” Redfield said.

The CDC director stressed that wearing a mask is “not a political issue — it is a public health issue,” calling it a “personal responsibility” for everyone.

“I’m glad to see the president wear a mask this week, and the vice president,” Redfield said. “We need them to set the example.”

President Donald Trump wore a mask for the first time in public over the weekend on a visit to Walter Reed Medical Center.

Looking ahead, Redfield said he’s worried about the upcoming fall and winter, when flu season begins.

“I do think the fall and the winter of 2020 and 2021 are going to be probably one of the most difficult times … in American public health because of … the co-occurrence of COVID and influenza,” he told JAMA.

Redfield stressed the importance of getting the flu vaccine, “because I think those two respiratory pathogens hitting this at the same time do have the potential to stress our health system.”

ABC News’ Eric Strauss contributed to this report.