Today is the second class of our current four class set. We will begin class with a casual conversation. Our discussion today is about the corona virus vaccine. I want you to introduce a topic from you lecture to me. Please listen to the audio clip and read the transcript simultaneously.

AILSA CHANG, HOST:

You have heard us say it a lot by now, but it is still true. The safest way to celebrate Thanksgiving this year is with members of your immediate household only. The level of coronavirus in this country right now means the chances of encountering an infected person while traveling to a bigger celebration or while sitting at the table are very real. But if we really want to turn this current surge around, epidemiologists say our leaders need to do more than just order people not to see friends and family. That brings us to Ellie Murray. She's one of those epidemiologists. She's at Boston University's School of Public Health, and she joins us now.

Welcome.

ELLIE MURRAY: Hi.

CHANG: So what do we know at this point about exactly where people are contracting the virus?

MURRAY: So when we look at the reports that the health departments are putting out at each state, a lot of that is happening in workplaces like meatpacking plants or warehouses, institutional settings like prisons or retirement communities. And then there's also a lot that's happening in businesses like restaurants and bars where people spend a considerable amount of time indoors with a lot of people that they wouldn't normally be spending their time with.

CHANG: Well, what about small gatherings?

MURRAY: Yeah, so small gatherings definitely do have some risk. And I think one of the things that makes them particularly risky - things like sleepovers or dinner parties - is that people let down their guard. And they aren't wearing their masks, and they're indoors. And so small gatherings are definitely a potential source of infection, but it doesn't seem like there's any clear evidence that those are what are particularly driving the infection. If we can get infections down across the board, those small gatherings will become safer.

CHANG: I'm wondering - when we see some states like Minnesota restricting even outdoor gatherings of multiple households, does the science actually back up that those kinds of decisions are helpful?

MURRAY: So every gathering has some potential for transmission. But outdoor gatherings, especially ones that are, you know, really outdoors in the fresh air - we're not talking those tents or bubbles - and people have space to spread out - that is the lowest-risk possible situation. And that should really be the last thing that we're putting regulation in place to stop. You know, we've seen a lot of governments in the summer were closing beaches and closing parks. And those are actually where we should be encouraging people to go instead of restaurants and things like that.

CHANG: Well, what about curfews? We've seen some states impose a curfew on bars and restaurants. What's the evidence that making people go home at a certain time helps limit spread?

MURRAY: So I've spoken with a lot of other epidemiologists and public health specialists, and we're not really sure at all where the justification in terms of the science for these curfews is. I think that the assumption is that some people will decrease their planned activities because of the curfews.

CHANG: I mean, wouldn't people just go out earlier?

MURRAY: Right. So this is the concern. More people have concentrated in a smaller time window.

CHANG: Well, then what should local authorities focus on in trying to make the biggest dent possible in transmission these days?

MURRAY: Yeah. So I think that, you know, we have seen really large spread happening from things like bars especially. And I think that those places need to be closed down for at least until we can get a handle on the current surge. And also, governments need to be thinking about how to help support the businesses and employees in being able to close those places down - restaurants, bars - also, stronger enforcement of distancing in workplaces. There are a lot of sort of ways that governments can intervene to minimize the amounts of contacts people are having, and they really need to step up and do that.

CHANG: Ellie Murray is an epidemiologist at Boston University's School of Public Health.

Thanks so much for being with us today.

MURRAY: Thanks for having me.