Prognosis
Delta Variant Gains Steam in Undervaccinated U.S. Counties
- Study highlights concern about breeding grounds for mutations
- Higher vaccination areas seeing growth of gamma variant
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Early evidence suggests that the highly contagious delta variant, which has prompted concern worldwide as it leads to new surges of Covid-19 across the globe, is spreading in undervaccinated pockets of the U.S.
The genomics firm Helix analyzed about 20,000 samples from Covid-19 tests across more than 700 U.S. counties. It found that cases of the variant first documented in India appear to be growing far faster in counties with lower vaccination rates than in areas that have higher rates.