Highly Contagious Delta Variant of COVID That Ravaged India Is Spreading in the U.S.

John Paraskevas/Newsday via Getty A nurse administers COVID-19 test

The highly contagious Delta variant of COVID-19 that spread rapidly in India is now in the U.S., worrying health experts with large portions of the country still unvaccinated.

The variant has been found in more than 6% of cases in the U.S., and may be the cause of more than 18% in some parts of the country, the Centers for Disease Control said.

The strain, which was first identified in India and is also known as B.1.617.2, has taken hold in the U.K. and represents 60% of the country's cases. The U.K. was set to ease COVID-19 restrictions on June 21, but is reevaluating reopening due to the increase in cases.

"We cannot let that happen in the United States," Dr. Anthony Fauci, the nation's top infectious diseases expert, said during a White House COVID-19 briefing on Tuesday.

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Fauci said that the variant may be "associated with increased disease severity" and a higher risk of hospitalization from COVID-19, but that the vaccines have been effective against it. A study from Public Health England found that people who were fully inoculated with Pfizer's vaccine had 88% protection against the Delta strain, NPR reported. A single dose of the vaccine offered 33% protection, highlighting the need for both doses.

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With the U.K. vaccinating citizens at a slower rate, and just beginning to expand eligibility to people in their twenties, Fauci said their situation is a "powerful argument" for vaccination. He emphasized the need for people to get both doses of Pfizer or Moderna's vaccines, "and for those who have still not been vaccinated yet, please get vaccinated."

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President Joe Biden has set a goal of getting 70% of Americans vaccinated by July 4, though inoculations have slowed in recent weeks. As of June 9, 51.8% of all Americans have received at least one dose of a COVID-19 vaccine and 42.5% are fully vaccinated, according to the CDC. Among vaccine-eligible Americans, those aged 12 and up, 61.3% have received at least one dose and 50.3% are fully vaccinated.

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