COVID-19 Variants

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Viruses are always changing (mutating) and new variants (or strains) of a virus are expected.

The best way to slow the emergence of new variants is to reduce the spread of infection by taking measures to protect yourself, the most important being getting vaccinated.

Which variants are concerning?

The Centers for Disease Control and Prevention (CDC) is tracking emerging variants – including the Delta and Omicron variants, which are both classified as variants of concern.

The Delta variant, which is currently the predominant variant of the virus in the United States and in North Carolina, is more than twice as contagious as previous variants, and some data suggests it might cause more severe illness than previous strains in unvaccinated persons.

The Omicron variant was first classified as a variant of concern on Nov. 26, 2021, by the World Health Organization (WHO) and on Nov. 30, 2021, by the United States. It’s been detected in many countries, including the United States.

The CDC and NCDHHS are monitoring and continuing to learn about these variants.

How contagious are the variants?

The Delta variant is more than twice as contagious as previous variants, and some data suggests it might cause more severe illness than previous strains in unvaccinated persons.

While the disease caused by the original virus spread from one person to an average of two or three people, COVID-19 caused by the Delta variant is spreading from one person to an average of six people. And nearly all of that spread is happening amongst people who are not vaccinated.

Early evidence suggests that the Omicron variant is two to three times as contagious the Delta variant, making it four to six times as contagious as the original COVID-19 virus. Data collected so far show more rapid waning of protection after the primary vaccination series than was seen with Delta or other variants, although vaccines are still effective at preventing severe disease. Protection against Omicron increases greatly after a booster dose

More data are needed to know if Omicron infections are different from Delta in severity. More data are also needed to know whether reinfections and infections in people who are up to date on their vaccination schedule occur more frequently with Omicron.

How can I protect myself and others?