A coronavirus vaccine could be ready for distribution by the end of the year, and distributed to Americans in 2021, the nation's top infectious disease specialist told lawmakers Friday.

While it typically takes years to develop vaccines, new technologies, the lack of bureaucratic red tape, and the human body's robust immune response to COVID-19 have hastened the process, Dr. Anthony Fauci said.

"From everything we've seen now — in the animal data, as well as the human data — we feel cautiously optimistic that we will have a vaccine by the end of this year and as we go into 2021," said Fauci, director of the National Institute of Allergy and Infectious Diseases. "I don't think it's dreaming."

In contrast to the decades-long search for an HIV vaccine, COVID-19 is more likely to respond to a vaccine, Fauci said. HIV vaccine development has been so difficult because the body doesn't make a strong immune response to that virus, he explained. With COVID-19, the immune response is much stronger.

The administration is preparing for wide distribution, with the hope that the current vaccine candidate will prove effective in Phase 3 trials, Fauci said. Fauci said the administration is taking "financial risk" to prepare for distribution once the vaccine is shown to be safe and effective.

The Department of Defense and Centers for Disease Control and Prevention would work together to distribute a vaccine to Americans in phases. Government committees will determine who needs the vaccine first, Fauci said. That will likely include essential workers and people at greater risk.

The Food and Drug Administration would still need to grant final approval before any vaccine is administered to the public.

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