Moncef Slaoui, the chief scientific adviser for Operation Warp Speed, says that some Americans could start receiving a COVID-19 vaccine by the second week of December.

PBS Newshour correspondent John Yang reflects on his experience participating in Moderna's coronavirus vaccine trial. "It started off with self-interest — I wanted to get the vaccine sooner," he says.

Albert Bourla, head of the pharmaceutical giant, discusses plans for distributing its vaccine, which it says is 95% effective, and explains the timing of his $5.6 mllion sale of Pfizer stock.

Hundreds of thousands of people in China have already received this vaccine. Now, preliminary trials are showing promising results, although it's too early to say whether it can prevent disease.

Doctors at Emory University on Monday celebrated the news from biotech company Moderna that its COVID-19 vaccine is 94.5% effective, saying the breakthrough is a historic day for science and that the next frontier will be to convince Americans to take it when the vaccine becomes available.

Although the leading vaccine candidates are not yet officially approved, the drug companies are administering them to hundreds of thousands of people.

Wealthy countries have a strategy to secure doses of any forthcoming vaccines. And that's creating a problem for lower-income nations.

Facebook's goal is to help messages about the safety and efficacy of vaccines reach a broad group of people, while prohibiting ads with misinformation that could harm public health efforts.

The nation’s leading infectious disease doctor issued a strong rebuke of the White House on Thursday, saying he would not support political meddling in the rush to make a coronavirus vaccine available to the American public.

"The first question is, is the vaccine safe? Frankly, I'm not going to trust the federal government's opinion," Democratic Gov. Andrew Cuomo said at a news conference.

Everyone 6 months of age and older is encouraged to get a flu shot this year.

The Army is working with private industry to create a coronavirus vaccine, but also working on its own. The military service has a history of creating vaccines and making medical breakthroughs.

Moderna is currently developing a promising, yet still unproven, vaccine against the coronavirus. But Moderna executives have already sold tens of millions of dollars worth of stock in the company.

Dr. Moncef Slaoui, chief adviser to the administration's effort to develop a COVID-19 vaccine, said having a vaccine by next month was "not impossible." But a longer timetable appears more likely.

Dr. Paul Offit, who serves on the Food and Drug Administration's vaccine advisory board, says he doesn't think an effective vaccine that's undergone adequate testing can be ready this year.