As COVID-19 cases in the U.S. continue to climb, Pfizer's vaccine received key approval from the Centers for Disease Control and Prevention.

Federal officials say the first shipments of the newly authorized Pfizer vaccine are on the way. The CDC says vaccinations will begin Monday.

The approval process and the vaccine itself continue to create doubts among some who say everything is happening too quickly.

"It needs to get tested more…it got approved too early," says Yonkers resident Allen Fontecchio. "The COVID'S been out for a year and it needs more testing for the side effects of the vaccine."

Meanwhile, Dr. Anthony Fauci has reassured that no corners were cut in the research and development of the drug.

"Where there is skepticism and concern, I think you counter it with a real firm argument," he says. "The process is the quickest we've done in history, that's because of the advances in the techniques."

Medical experts say the coronavirus death toll in the U.S. has already surpassed the number of fatalities during World War II.

"I think it's a good idea, a lot of people are dying," says Yonkers resident Ashley Lacouture. "We might as well have something to prevent it. It happened with the smallpox and other things we have vaccines for now."

Under the federal government plan, health care workers and nursing home residents will be first in line for the vaccine.

Patients and caregivers will receive fact sheets listing the risks and benefits of the drug.