What we know about the new COVID-19 strains

Last updated: Apr 20, 2021
Learn about the various COVID-19 strains.

Seeing healthcare workers, family, and friends get a COVID-19 vaccine can give us hope that we are starting to stem the tide of the pandemic. But what about the new variant strains of COVID-19? All viruses mutate over time. SARS-CoV-2, the virus causing COVID-19 infections, is no exception.

While most mutations have little impact in normal viruses, understanding the new strains is important. We are still in the midst of a pandemic: The number of people getting sick in the U.S. is on the rise again. And until more people are vaccinated, new strains will keep attacking the community.

Understandably, the new strains are causing concern. Will the vaccines work against the new strains? Are the new strains more infectious? Are they more deadly? Studies are ongoing to help answer many questions. But here are answers based on what we know now to some frequently asked questions about five common COVID-19 variants.

What are the new COVID-19 strains?

Since the COVID-19 epidemic began, new strains have been circulating all over the world. To keep track of them, health agencies follow them as they emerge. These are five common variants.

  • The Alpha variant. Also known as the U.K. strain, it was first discovered in the United Kingdom in September 2020. By January 2021, it had made its way to 12 U.S. states and 30 other countries. A report earlier this year suggested it might be associated with a higher risk of death, but more research is needed.
  • The Beta variant, known as the South Africa strain, shares similar mutations with the Alpha variant. It was first identified in South Africa in early December 2020. By late January 2021, it had appeared in the United States. As of now, there is no evidence suggesting that it leads to symptoms that are either more or less severe.
  • The Gamma variant is also known as the Brazil strain. It was first identified in travelers coming from Brazil. It arrived in the United States in January 2021. This strain might be resistant to antibodies from previous exposure or vaccines. That may lead to reinfection.
  • The Delta variant was first discovered in India in March. Today, it’s the most common variant in the United States. It appears to be a more transmissible strain, and it may respond slightly less well to the vaccine. However, if you’re vaccinated and you do get sick, your symptoms are much less likely to be severe. The Delta variant may also not respond as well to monoclonal antibody treatments. (Monoclonal antibodies are manmade proteins. They mimic how the immune system fights off viruses and other pathogens.)
  • The Epsilon variant. Also called the West Coast strain, it includes two closely related strains detected in Southern California in late 2020. It remains a concern in the state. It may not respond as well as other variants to monoclonal antibody treatments.

What are the symptoms of the new strains?

There are no definitive answers, yet. So far, most research suggests that the new strains are no more likely than the original COVID-19 strain to cause severe illness or death. More studies are needed before we can be certain.

How easily can the new strains be spread?

The state and the CDC are still learning how transmissible the new strains are. Some strains appear to spread more easily and quickly. For instance, the Alpha and Beta strains may be 50% more transmissible. The Delta strain may be as much as 60% more transmissible than the Alpha strain. And the Gamma strain might not be recognized by antibodies. That raises the risk of reinfection or spread even after vaccination. More research is needed on all strains before we know for sure how easily they can spread or how severely ill they can make you.

How can I protect myself against the new strains?

First and foremost, get a COVID-19 vaccine. It will help protect you from the original strain of COVID-19 and most variants that are now spreading in the United States. One study found that getting two doses of the Pfizer-BioNTech vaccine was about 94% effective in people with the Alpha variant. And it was 88% effective in those with the Delta variant. More studies are needed, but we also know that even if you’re infected with a variant, the vaccine is very effective at preventing severe symptoms, hospitalization, and death. To schedule your vaccine, visit myturn.ca.gov.

Additionally, keep doing what you can to help curb the spread of all strains of the virus and protect yourself from getting sick:

  • Wash your hands.
  • Wear a mask indoors.
  • Social distance.
  • Follow local regulations.

It’s also important to stay up to date on what’s happening in your community. For instance, Los Angeles County recently reinstated a mandate that everyone must wear a mask indoors even if they are fully vaccinated. Officials made the decision after seeing a seven-fold rise in COVID-19 cases in just one month. Their goal is to slow the spread of the Delta variant. It caused 71% of new infections between June 27 and July 3.

Wearing a mask with multiple layers or two single-layer (cloth and surgical) masks can provide added protection. But N95 and medical masks should be reserved for healthcare workers.

The pandemic has been tough for many of us, and the new strains can seem like a setback. While there are still a lot of questions, we trust the scientists who are tirelessly working to help curb the spread of the virus. In the meantime, we are here to help you get the answers — and the care — you need.

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