Transcript for Concerns grow over COVID-19 Delta variant
Now, to the other major news we're following this Wednesday night, the coronavirus back at home. The growing concern about the delta variant, first seen in India. Highly transmissible and potentially more severe. Tonight, described as covid on and what authorities are now seeing in the U.S., spreading quickly. And what you should know. And we've also learned they're now studying at least 80 countries with reported cases of mutations of this variant already. Here's ABC's whit Johnson tonight. Reporter: Tonight, the delta variant threatening to derail progress against the pandemic. The highly contagious strain now identified in at least 37 states. If you're living in a part of the country where there is a low degree of vaccination, or if you yourself are not vaccinated, you're clearly vulnerable, because this is basically covid-19 on steroids. Reporter: Officials have warned the delta variant is more transmissible and may cause more severe disease. Some states with lower vaccination rates seeing a nearly 20% increase in covid cases over the last two weeks. In Tennessee, where just a third of the state is fully vaccinated, the delta variant is already taking hold. At least ten cases in the Memphis area. We have made tremendous progress and we don't want to lose what we've gained. Reporter: The delta variant, first identified in India, now making up about 90% of cases in the uk. Some experts warn it could become the dominant strain here in the U.S. It is far more contagious than any variant we have seen throughout this entire pandemic. It also appears to be a little bit more deadly for people who get infected. Reporter: But act veens appear to be effective against us and reports suggest some symptoms of the delta variant may be more prevalent. Headaches and sore throat are the key features of this variant. It's something to keep an eye on. Reporter: And Dell David, the delta variant has been identified in more than 80 countries. Officials are tracking so-called delta-plus variants which have additional mutations, something they're watching very closely. David? And of course we'll stay on this.
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