The first dose of the coronavirus vaccine is likely to become available to some high-risk Americans in late December or early January, Dr Anthony Fauci, Director of United States’ National Institute of Allergy and Infectious Diseases, said on Thursday, reported Reuters. The availability of the vaccine will however be subject to safety and efficacy.

Based on current projections from vaccine front-runners Moderna and Pfizer, Americans will likely know “sometime in December whether or not we have a safe and effective vaccine,” Fauci said in a live chat on Twitter and Facebook.

“The first interim look at trial results should be within the next few weeks,” he said, while speaking to Dr Francis Collins, Director of the National Institutes of Health.

Fauci however warned that even with an effective vaccine, it will take time to get back to normalcy as vaccine-induced immunity is built. He said life would likely not get back to normal “until the end of 2021 at least.”

On Tuesday, drug company Pfizer had said that it could supply about 40 million doses of a coronavirus vaccine to the United States this year itself and a 100 million doses by March 2021. Moderna on Thursday said it was on track to deliver interim data from its large, late-stage trial next month, according to Reuters.

On Monday, another pharmaceutical company AstraZeneca said that the coronavirus vaccine being developed by the University of Oxford produces an immune response in both old and young adults. The company however did not say when the results of the Phase 3 trials would be published. A vaccine is deemed safe to be commercially available only after Phase 3 trials – a much larger efficacy trial involving thousands of participants.

Pfizer, AstraZeneca and another drug company Moderna are among the front-runners in the global race to produce a vaccine to fight the infection.