A key official in the U.S. government warned the public that a worse health situation could come this fall, with a combination of the COVID-19 pandemic and the yearly flu season.

Robert Redfield, director of the U.S. Centers for Disease Control and Prevention (CDC), told online health publisher WebMD that the country could face the worst fall ever in history from the perspective of public health.

But that could only happen if people in the U.S. remain reluctant about masks, social distancing, hand washing and avoiding crowds.

"You do those four things, it will bring this outbreak down," Redfield told WebMD chief medical officer Dr. John Whyte during a video call.

"But if we don't do that, as I said last April, this could be the worst fall from a public health perspective, we've ever had," he added.

Redfield made it clear that Americans are not doing enough to prevent the spread of COVID-19. That's the reason why confirmed cases in the country increased by one million in just three weeks.

He is also confident that COVID-19 will be one of the main causes of death in the U.S. in 2020, as the disease have killed more than 160,000 people in the country.

(Cover photo: Redfield attends a meeting in Washington, D.C., U.S., June 30, 2020. /CFP)