BBC News: "Should we wear face masks" with Jeremy Howard
00:00:00.000 | Now, should everyone wear a face mask? That's one of the big questions people all over the
00:00:05.400 | world are asking at the minute. This week, Singapore made wearing masks compulsory in
00:00:10.440 | public and in the state of New York. They are also required whenever social distancing
00:00:15.100 | is not possible. But many countries are still advising people not to use them unless they
00:00:20.180 | are sick.
00:00:21.180 | Well, to help us understand the science behind this, I'm joined by Jeremy Howard, a scientist
00:00:24.960 | at the University of San Francisco and co-founder of the FAST.AI Research Institute. Jeremy,
00:00:31.200 | thanks for joining us. You've reviewed the research around face masks. What are the main
00:00:34.960 | things that you found?
00:00:35.960 | Yes, I'm the lead author on the latest study here, which is a cross-disciplinary international
00:00:41.520 | review of the evidence around face masks from 19 of the top world experts in this area.
00:00:46.560 | And what we found is that the evidence is surprisingly clear. When we speak, we can
00:00:51.500 | transmit this disease by little droplets that come out of our mouth so small that we can't
00:00:56.220 | see them. And any kind of simple cloth mask or paper towel mask actually stops them in
00:01:01.280 | their tracks, about 99 percent effective at stopping them.
00:01:05.340 | We looked at the data around this and we saw that there's actually countries that have
00:01:09.600 | already figured out how to keep their economy going without mass destruction like we're
00:01:14.520 | seeing in London and New York, mass death. For example, Taiwan and Hong Kong, their economies
00:01:20.440 | largely continuing as usual with just a few social distancing measures, but not a lockdown.
00:01:25.840 | And they only have 10 deaths each, despite Taiwan, for example, having a population of
00:01:30.640 | 30 million. They're doing the testing, the tracing, the quarantine of potentially infected
00:01:36.240 | and face masks. There's a magic four-piece solution, which we're already seeing working
00:01:41.480 | and face masks are part of it.
00:01:43.400 | Yeah, it's really interesting you mentioned Taiwan and Hong Kong there. Why is there this
00:01:46.480 | divide between Asia and the West over this? Because countries that you mentioned, Japan,
00:01:51.600 | China, Korea, Thailand, Hong Kong, masks have been the norm for quite a few years now.
00:01:55.960 | Well, there's been an important change in East Asia. Masks have been the norm for people
00:02:01.000 | with symptoms. And unfortunately, that doesn't really help in this case because we now know
00:02:05.800 | that about half of the infections come from people that don't have symptoms at the time
00:02:10.280 | that the infection happens. So what happened is in Taiwan and Hong Kong, they were pretty
00:02:14.920 | close to the epicenter of this pandemic. They had people on the ground in Wuhan. They saw
00:02:20.460 | the asymptomatic and pre-symptomatic spread. And so they very quickly realized, OK, everybody
00:02:26.080 | needs to wear a mask. They already had the mask wearing culture because they have, unfortunately,
00:02:30.640 | a history of respiratory pandemics in that region. So they know about the importance
00:02:34.600 | of masks. And with this vital new scientific fact, which is you can transmit the disease,
00:02:39.680 | even if you don't know who you have it, very quickly, everybody realized we need everybody
00:02:43.840 | wearing masks. Otherwise, people are at risk. And briefly, Jeremy, your advice then to anyone
00:02:49.120 | in a city with a significant coronavirus outbreak as well as social distancing would be simply
00:02:53.720 | to wear a mask. Yes. And really any mask, you can literally take a piece of paper towel,
00:02:58.840 | you can staple the rubber band onto each end and you can stick it over your face. And that
00:03:02.480 | is incredibly effective at stopping the droplets. It won't necessarily keep you safe from those
00:03:07.200 | around you, but it will keep those around you safe from you. So if you make sure that
00:03:11.340 | everywhere you go, everybody's wearing a mask, that's going to do a great job of keeping
00:03:15.360 | you safe. So we really need help here from governments, from unions. And so London today,
00:03:20.560 | the London mayor is saying we want to enforce masks throughout our city. And this is why.
00:03:26.840 | Jeremy Howard, really interesting to talk to you about that. That's Jeremy Howard live
00:03:29.960 | there from Houston in Texas. Thanks so much.