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The Delta variant: What you need to know

A young man getting a vaccine.

The Delta variant of the coronavirus, known as B.1.617.2, is raising some concerns among health experts. Why? Because it spreads more easily. But there's good news too: So far, COVID-19 vaccines work well against this strain of the virus.

Here's what to know to help keep yourself and your loved ones safe.

Q. What is the Delta variant?

A. Many viruses mutate over time. The Delta variant is a new mutation of the coronavirus that was first found in India. It has now spread to more than 100 countries. In fact, it has become the dominant strain throughout the world, including in the United States.

Q. Why is it a potential problem?

A. The Centers for Disease Control and Prevention calls Delta a "variant of concern." That means it has some qualities that require close monitoring. In Delta's case:

  • It is more contagious.
  • It may be resistant to some treatments.

Q. Why is it important to be fully vaccinated?

A. If you are fully vaccinated, you are less likely to get severely ill—from Delta or other variants. For two-dose vaccines, like Pfizer's and Moderna's, that second shot is crucial. It may offer more protection against Delta than the first shot alone.

In the United Kingdom, one shot of the Pfizer vaccine was shown to be only 33% effective against Delta. But two doses were 88% effective.

The bottom line: To slow the spread of Delta, it's important for everyone to be fully vaccinated as soon as they can be.

Are your kids not yet eligible for a COVID-19 vaccine? You can still take certain steps to reduce their risk of getting sick.

Reviewed 10/13/2021

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