Transcript for New evidence that ‘double-masking’ may be better at protecting against COVID-19
In the meantime, we move onto other news this Wednesday evening. The new CDC report showing that tightly fitted masks make a difference. And a tightly fitted mask with a cloth mask over it is also effective. What the numbers show in this new study and word tonight from the new CDC director. And of course, the race to vaccinate in this country. 33,738,000 people getting at least one dose. That's 10.2% of the population, as we continue to track this. ABC's whit Johnson tonight at New York's citifield. Reporter: Tonight, the CDC is out with new evidence that shows how important it is how your the CDC conducted experiences to assess two ways of improving the fit of masks. First, wearing a medical procedure mask and fitting a cloth mask over it. Second, wearing a medical procedure mask, then knotting the ear loops. Each scenario could reduce the risk of transmission by more than 95%. The bottom line is this masks work, and they work best when they have a good fit, and are worn correctly. Reporter: The proper use of masks and getting more people vaccinated, all the more critical with new variants raging across the country. California today reporting its first two cases of the more contagious south African variant. We have vaccines that work well against it, and obviously we are going to be planning if necessary to upgrade vaccines in the future if we ever have to do that. Reporter: Some experts suggesting the increase in mutations may require vaccine shots every year in the near future. I you this we're going to try to configure a vaccine that has much more durable and widespread protection, but that may take a few years. Reporter: The Biden administration says the nation's vaccine supply has increased by 30% since taking office. The U.S. Now averaging nearly 1.5 million vaccinations a day. But getting vaccinated still a challenge. Long lines from Texas to Illinois. In New York City, Citi field opening as a vaccination site. But opening day comes with a dose of reality -- limited supply. For now the stadium can only offer about 200 shots per day. We can do 5,000 vaccinations a day here. Reporter: David, back to the new study on masks, whether it's wearing two masks or twisting the ear loops, it is all about having a snug fit. And to be clear, the CDC is not recommending any changes to its guidelines, they just want to make sure most importantly that everyone is wearing that mask. David? That's right, whit, in their words, the bottom line, masks work, they work best when they have a good fit. So, either wear it very fitted, with that nose clip, or the cloth mask over it. Those are the two scenarios they put out there today, just to say, remember, everyone, that the fit of the mask actually makes a difference. Whit Johnson, thank you. When we come back here, we
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