WASHINGTON - It will be the late second quarter or third quarter of 2021 before a COVID-19 vaccine is generally available to the American public, said Director of the US Centers for Disease Control and Prevention (CDC) Robert Redfield on Wednesday.

During a Senate Appropriations subcommittee hearing, Redfield said he thought that there would be vaccine initially available sometime between November and December, but "very limited supply and will have to be prioritized."

"If you're asking me when is it going to be generally available to the American public, so we can begin to take advantage of vaccine to get back to our regular life, I think we're probably looking at late second quarter, third quarter 2021," he said.

Even if a vaccine for COVID-19 was released, it would take "six to nine months" for enough people to get it to create immunity, according to Redfield.

"In order to have enough of us immunized so we have immunity, I think it's going to take us six to nine months," he said.

In this time, it is important for people to embrace mitigation steps such as physically distancing, mask use and avoiding crowds, Redfield said, adding wearing a face mask might provide better protection against COVID-19 than a vaccine.

"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 the immunogenicity may be 70 percent," he said.

"If I don't get an immune response, the vaccine is not going to protect me. This face mask will," Redfield said, adding that the American public has not yet embraced the use of face masks to a level that could effectively control the outbreak.

"I do want to keep asking the American public to take the responsibility, particularly the 18 to 25 year olds where we're seeing the outbreak in America continue to go like this," Redfield said.

The US Department of Health and Human Services (HHS) and Department of Defense released two documents Wednesday outlining detailed strategy of the US government to deliver COVID-19 vaccine doses to the American people.

The documents provide a strategic distribution overview along with an interim playbook for state, tribal, territorial, and local public health programs and their partners on how to plan and operationalize a vaccination response to COVID-19, said the HHS.

Months into the pandemic, the United States has recorded more than 6.6 million confirmed COVID-19 cases and over 196,400 deaths by Wednesday afternoon, according to a tally of Johns Hopkins University.