Image by Karolina Grabowska

Top United States infectious disease expert Anthony Fauci told a House panel today that he is "cautiously optimistic" that a COVID vaccine will be made available in the US in late fall or early winter, CNN reports.

"We hope that by the time we get into late fall and early winter, we will have in fact a vaccine that we can say that would be safe and effective," he told a House subcommittee that was formed to investigate Trump's response to the coronavirus pandemic.

"One can never guarantee the safety or effectiveness unless you do the trial, but we are cautiously optimistic this will be successful," he added.

Fauci said that vaccines currently in development showed a healthy response, triggering a "neutralizing antibody response" that's comparable to the response in those who had already recovered from COVID-19.

The news comes after a large-scale phase three trial of a vaccine developed by biotech Moderna kicked off on Monday, becoming the first US-based coronavirus vaccine to do so. About 30,000 adult volunteers will be part of the trial across 89 US research sites.

In a Thursday ABC News interview, Fauci stressed the importance of wearing masks to “not only protect us against COVID-19, but also help protect us against influenza” during this year's upcoming flu season.

"Go out there and get your flu shot when the flu vaccine becomes available," he added.