Despite the logistical challenges, Bill and Melinda Gates Foundation co-chair Melinda Gates is staying very hopeful on when a large percentage of the U.S. population may get their COVID-19 vaccine.

“I think by the middle of next year you could see half the U.S. vaccinated, because we have these two first mRNA vaccines coming. But then, there are three more [vaccines] that are going to come very quickly behind that. Those are even easier to manufacture. And so, I think you'll start to see lots and lots of doses available,” Gates told Yahoo Finance.

This week has delivered several important new developments on the vaccine front, raising the hopes of achieving the goal put forth by Gates.

A panel of outside experts is set to convene Thursday to advise the U.S Food and Drug Administration (FDA) on the Pfizer/BioNTech COVID-19 vaccine, according to The Wall Street Journal. The vaccine has shown an efficacy rate of 95%, and is seen as a near lock to be approved by the FDA within days. U.K. based 90-year-old Margaret Keenan became the first person in the world to be inoculated for COVID-19 on Tuesday. Keenan received the Pfizer/BioNTech vaccine.

Meanwhile, Morderna has applied for emergency use authorization for its COVID-19 vaccine. It could be approved as early as Dec. 21.

Positive news on the vaccine rollout come as the U.S. faces even more grim numbers on the pandemic. The U.S. saw its highest one-day death toll from COVID-19 on Wednesday with 3,054 deaths, according to data from the Covid Tracking Project. On average, more than 200,000 Americans are testing positive for the coronavirus each day.

The Bill and Melinda Gates Foundation announced Thursday it’s stepping up its fight against the pandemic.

On Thursday the largest private foundation in the world said it will commit an additional $250 million to support the research, development and equitable delivery of COVID-19 tests, treatments and vaccines. It marks the foundation’s largest single contribution to the COVID-19 response to date. The foundation’s total commitments to the global COVID-19 response now tallies $1.75 billion.

Brian Sozzi is an editor-at-large and anchor at Yahoo Finance. Follow Sozzi on Twitter @BrianSozzi and on LinkedIn.

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