What Is the New COVID-19 Strain, and Does It Infect Kids More Easily?

In addition to all the news about the COVID-19 vaccine, you’ve probably been hearing a lot about a new strain of COVID-19 that originated in the UK, and has since spread to the U.S. and other countries.

Researchers are still gathering information about this new variant, including whether it might more easily infect children than previous strains of COVID-19.

Connecticut Children’s Physician-in-Chief Juan Salazar, MD, MPH, shares what we know so far.


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What does it mean that there’s a new “strain” or “variant” of COVID-19?

A strain or variant is a slightly different version of a virus. Viruses grow inside a person’s body by making copies of themselves. Sometimes, these copies contain random differences, or mutations. Most of the time mutations don’t change anything significant. Sometimes they harm a virus. And sometimes they help it.

If a mutated version of a virus survives, it can start spreading in a community. For example, every flu season, there are usually several strains of the flu going around.

That’s what we’re hearing about now with the new strain of COVID-19, which has been labeled B117.

> Related: Why Your Child Needs Their Flu Shot ASAP

What is the B117 variant of COVID-19?

This new strain of COVID-19 was first reported in the UK, so you may have heard it referred to as “the UK variant.” Scientists have labeled it B.1.1.7 or B117. It has since been detected in dozens of countries, including the United States. Connecticut recently confirmed its first cases.

Other, different strains of COVID-19 have been identified around the globe, including in South Africa and Nigeria. They seem similar to B117, but we have less information about these strains.


How is the B117 variant of COVID-19 different?

Scientists are still gathering information. So far, the B117 strain appears to spread much more easily than previous strains of COVID-19 – some data shows that it spreads up to 70% more easily – probably due to a mutation in how the virus enters human cells.

The World Health Organization says the new strain is responsible for more than half of new COVID-19 infections in the UK.

> Related: What Should I Do When My Child Has a Common Cold During COVID-19?

Is the B117 strain of COVID-19 more dangerous?

No. From what we know so far, the new B117 variant does not appear to cause more serious illness or increased risk of death than previous strains of COVID-19.

Are children more likely to get sick from this new strain of COVID-19?

Up until this point, for reasons that we still don’t know, COVID-19 was more likely to infect adults than children.

But some researchers have suggested that the new B117 strain may just as easily infect children as adults, perhaps due to changes in how the virus enters human cells. For example, Britain is seeing high numbers of the B117 strain in younger people under the age of 20.

We need more data before we can know whether this is because children are actually more susceptible to the new B117 strain, or if the numbers are due to other factors, like the result of a growing outbreak and more testing.

Again, so far, the new strain does not appear to lead to more serious illness for the individuals it infects, including young people and children.

Team member in full personal protective equipment performs a COVID-19 test.

Will the COVID-19 vaccine still work against the B117 strain? Why?

Pfizer and Moderna have both said their COVID-19 vaccines will work against the B117 variant. This is likely because the part of the virus that has mutated isn’t involved in how the vaccines work.

> Related: Now That There’s a COVID-19 Vaccine, When Will Life Go Back to “Normal”?

Should my family be worried about new strains of COVID-19?

We need to be more careful than ever, since numerous states, including Connecticut, have reported cases of the B117 strain and we know that it spreads very easily.

Now more than ever, it’s important to wear masks, social distance and avoid risky activities. Get tested and self-quarantine if you might be sick. As always, practice great hand hygiene.

And once the COVID-19 vaccine becomes available to your family, it will be important to get both doses.

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