Health Library

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. Here are the basics on variants.

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.

The coronavirus that causes COVID-19 has gone through this type of changing process many times during the pandemic. Each time a new coronavirus variant emerges, the World Health Organization (WHO) gives it a name based on a letter from the Greek alphabet. Variants of note include alpha, delta, and omicron.

How Can Variants Differ From the Original Virus?

Variants can differ from the original virus based on:

• how contagious they are
• how sick they make people
• how they respond to vaccines and medicines
• whether people can get infected with the virus more than once

What Can Protect People From These Variants?

In general, the steps that experts have recommended to protect us from the original virus also can work to stop the spread of other variants.

It is still very important to keep doing the things that are in our control, such as:

• getting vaccinated and getting all recommended booster shots
• washing hands well and often
• testing and staying home when necessary
• making sure indoor spaces are well-ventilated

Masks are no longer required in most public places in the U.S. But it’s still a good idea for people to wear them in some settings. For example, experts still recommend wearing masks when indoors or in crowded outdoor activities in areas with a high rate of COVID-19 infections. People at high risk of getting very sick with COVID-19 (such as those with weak immune systems) should wear masks indoors even if the rate of COVID-19 in their area isn’t that high. And it can be helpful to still wear masks in health care settings like a hospital or doctor’s office.

What Else Should I Know?

Scientists constantly watch for new variants, but it takes time to gather data. Sometimes information gets published before experts know what we’re dealing with. This can make a situation sound scarier than it really is. It’s best to wait for the facts to become clear, which can take weeks or longer, before reacting to news of a new variant.