Moderna is the second drug company in a week to announce preliminary results showing its coronavirus vaccine is highly effective. Dow futures are rallying on the news.

Marketplace’s Nova Safo has the latest, and the following is an edited transcript of his conversation with “Marketplace Morning Report” host Sabri Ben-Achour.

Sabri Ben-Achour: What are the details of Moderna’s announcement?

Nova Safo: Moderna says its coronavirus vaccine is almost 95% effective and may have helped prevent severe cases of COVID-19 among those who still got infected.

This was not unexpected news after Pfizer and BioNTech’s announcement last week, because both of these experimental vaccines use similar technology — new technology — relying on messenger RNA, a cell’s internal mechanism, to help fend off a viral infection.

The big difference is that, unlike Pfizer and BioNTech’s vaccine, Moderna’s version does not need to be kept in ultracold storage for transport, so it could be less of a logistical challenge to get it to people.

We should caution that neither of these vaccines currently have regulatory approval, but applications are expected in the next few weeks.

Ben-Achour: And then what happens? Presumably it’s going to take a while to get vaccines to people?

Safo: Yes. If approved, we could have tens of millions of doses by the end of this year, but we’ll need hundreds of millions. The U.S. has deals in place for both vaccines, to buy as many as a billion doses, so we’ll have enough, but it’ll take a while to manufacture that many.

It’s also unclear how many people will actually take them. Polling shows about 50% are willing to get vaccinated.

That’s not going to cut it. As one of the BioNTech scientists explained over the weekend, you need a high vaccination rate to get this pandemic under control.