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Coronavirus (COVID-19): Delta and Other Variants

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As the COVID-19 pandemic goes on, we’re hearing about “variants” of the virus that are different from the original one that started the pandemic. But what is a variant? And how could they affect children?

What Is a Variant?

When viruses spread, they make copies of themselves. As they do, they often mutate, or change, a little bit. A copy that is different from the original virus is called a variant. Sometimes variants don’t seem that different from the original virus. Others may have clear differences. For example, some variants may not be as good at spreading and might even disappear over time. Others may spread more easily or make people sicker than the original virus.

The coronavirus that causes COVID-19 has gone through this type of changing process many times during the pandemic. The variant now causing the most infections in the U.S. and other countries is called the Delta variant.

What Is Different About the Delta Variant?

The Delta variant:

  • Is more contagious. A person infected with the original virus was thought to pass it to about 2 other people. A person infected with the Delta variant spreads the virus to 4–6 people, or possibly more. The Delta variant seems to be one of the easiest viruses to catch.
  • Can be spread by people who are fully vaccinated. Large amounts of the Delta variant have been found in the noses and throats of people who aren’t vaccinated and in people who are vaccinated. But the virus disappears from vaccinated people much more quickly. So vaccinated people can spread it for a much shorter time than unvaccinated people.

What Is the Same About the Delta Variant?

The Delta variant causes similar symptoms to those of the original coronavirus. The steps we took to stop its spread will work for Delta and other variants.

As kids return to school, many can’t yet be vaccinated. So it’s even more important to focus on:

Are Other Variants Spreading?

The more a virus spreads and multiplies, the more likely new variants are to develop. The best way to prevent that is for everyone who can get vaccinated againt the virus to do so.

The COVID-19 vaccines are proven to reduce a person’s risk of infection from all variants. They also prevent severe disease, hospitalization, and death, even with the Delta variant. High vaccination rates are the key to fighting this pandemic and getting life back to normal.

What Else Should I Know?

Because the Delta variant is so contagious, it’s likely to infect many people who aren’t vaccinated. The COVID-19 vaccines are now available for adults and all children ages 5 and older. Everyone who is eligible should get vaccinated as soon as possible.

Date reviewed: November 2021