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COVID-19 variants: What's the concern?

Medically reviewed by Drugs.com. Last updated on March 23, 2021.

Viruses constantly change through mutation. Currently, several variants of the virus (SARS-CoV-2) that causes coronavirus disease 2019 (COVID-19) are creating concern because they contain mutations in the spike-like S protein that the virus uses to bind to and infect cells. These variants include:

  • A variant identified in the U.K. (B.1.1.7). This COVID-19 variant appears to spread more easily and might have an increased risk of death.
  • A variant identified in South Africa (B.1.351). This variant appears to spread more easily. It also has a moderate impact on the effectiveness of monoclonal antibody medications and moderately reduces the effectiveness of antibodies generated by a previous COVID-19 infection or COVID-19 vaccine.
  • A variant identified in Japan/Brazil (P.1). This variant has a moderate impact on the effectiveness of monoclonal antibody medications. It also reduces the effectiveness of antibodies generated by a previous COVID-19 infection or a COVID-19 vaccine.
  • A variant identified in the U.S. (California) (B.1.427). This variant appears to spread more easily. It also has a significant impact on the effectiveness of some treatments and moderately reduces the effectiveness of antibodies generated by a previous COVID-19 infection or COVID-19 vaccine.
  • A variant identified in the U.S. (California) (B.1.429). This variant appears to spread more easily. It also has a significant impact on the effectiveness of some treatments and moderately reduces the effectiveness of antibodies generated by a previous COVID-19 infection or COVID-19 vaccine.

The U.S. Centers for Disease Control and Prevention is also monitoring two variants identified in New York — B.1.526 and B.1.525 — and another variant identified in Brazil — P.2.

COVID-19 vaccines were developed based on the SARS-CoV-2 S protein before it had the mutations identified in these variants. While research suggests that COVID-19 vaccines have lower efficacy against the variants, the vaccines still appear to provide protection against severe COVID-19. Further research is needed.

In addition, vaccine manufacturers are also creating booster shots to improve protection against variants.

In the meantime, keep following precautions for avoiding infection with the COVID-19 virus.

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