COVID variants
Discovery
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Mary Parker

What You Should Know about COVID Variants

We are all slowly learning the Greek alphabet through news and commentary on SARS-CoV2 variants.

To enable new variants of the virus to be easily named rather than using complex scientific nomenclature, the World Health Organization (WHO) implemented a system using Greek letters. So far there have been 12, and while no strain of SARS-CoV-2 is a welcome event, some of the variants are definitely more feared than others.

What is a viral variant? 

A variant is defined as a viral genome with one or more mutations from the original virus. An identified “variant” might include a group of similar viral “lineages” with key mutations in common.

The concern with any variant is whether it can evade currently approved vaccines and antiviral treatments; whether it is more transmissible; and whether it is more dangerous than the original virus. As of this posting, the US Centers for Disease Control and Prevention (CDC) is monitoring two variants of concern (VOC): Delta, the fourth-named variant, and Omicron, the thirteenth-named variant, (though the World Health Organization still lists Alpha, Beta, and Gamma as VOC). Below you can find a roundup of news and research on each.

On a side note, just this week news has emerged about a variant in France called IHU, which was first identified in November. For now, scientists are just keeping an eye on the virus, while the WHO has labeled the variant as “under investigation.”

The most important takeaways from every scientific source are the same for every variant:

  • Get vaccinated.
  • Wear masks indoors in public, even if you are vaccinated, especially if you are in an area of high transmission.
  • Get tested if you are exposed to COVID or if you develop symptoms, and isolate if you are positive for COVID.

Information on all variants is continuously researched and updated, so it is necessary to check back with public health agencies and local regulations to continue the fight against COVID.

Delta variant

The Delta variant was first identified in India in late 2020 and spread quickly to become the dominant strain of SARS-CoV-2 in the U.S. until December 2021. Delta was discovered to be more contagious and spread faster than Alpha, Beta, or Gamma, which caused a leap in infections from June to July 2021. In late June the weekly average of cases in the US was 12,000. By the end of July, it had jumped to 60,000.

Though there were breakthrough cases in vaccinated people, the population most at risk is still the unvaccinated, including children.

CDC information and guidance on the Delta variant

5 Things to Know About the Delta Variant (Yale Medicine, updated Dec. 2021)

Omicron variant

Omicron is now the dominant strain in the U.S., surpassing Delta in December 2021. It was first identified by labs in South Africa and Botswana in November 2021, though where Omicron first emerged is unknown. It could well have started in other sub-Saharan countries with weaker surveillance.

As a recent variant, it is not yet known exactly how it will compare with Delta, which is responsible for more hospitalizations and deaths than Omicron. However, some epidemiologists think that Omicron will ultimately outcompete Delta, and usher in an era of fewer hospitalizations.

 According to the CDC, it is likely that Omicron is at least as transmissible as Delta and as vulnerable to vaccines. Based on what scientists know so far, existing vaccines are highly effective at preventing serious illness and hospitalizations

CDC information and guidance on the Omicron variant

Highly mutated SARS-CoV-2 Omicron variant sparks significant concern among global experts – What is known so far? (Travel medicine and infectious disease, Dec. 2021)