COVID-19 variants

What You Need to Know about COVID-19 Variants

About the Omicron Variant. The Omicron variant spreads more easily than the original virus that causes COVID-19 and the Delta variant. Forecasts by public health specialists predict a surge of COVID-19 cases.

About the Delta Variant. Vaccines continue to reduce a person’s risk of contracting the virus that causes COVID-19, including this variant. Vaccines are highly effective against severe illness, but the Delta variant causes more infections and spreads faster than earlier forms of the virus that causes COVID-19.

Viruses constantly change through mutation, and new variants of a virus are expected to occur. Sometimes new variants emerge and disappear. Other times, new variants persist. Numerous variants of the virus that causes COVID-19 are being tracked globally during this pandemic¹.

Top Things You Need to Know

1.   Variants 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, including getting a COVID-19 vaccine when available.
2.   Vaccines keep you from getting very sick, hospitalized, or dying from COVID-19.
3.   All COVID-19 tests can detect all variants, but they will not tell you which variant you have.

Vaccines

• Authorized COVID-19 vaccines (hyperlink to “Vaccine types explained” page) protect against Delta and other known variants.
• These vaccines effectively keep people from getting COVID-19, getting very sick, and dying.

Symptoms

• Most variants cause similar COVID-19 symptoms. (hyperlink to Symptoms page)
• Some variants may cause more people to get even sicker and die, for example, Alpha and Delta variants.

Masks

•   Wearing a mask is one way to reduce the spread of Delta and other variants.
•   It is recommended that people wear a mask indoors regardless of the level of transmission.
•   Wearing a mask is most important if you have a weakened immune system or if, because of your age or an underlying medical condition, you are at increased risk for severe disease (hyperlink to the “People at increased risk” page), or if someone in your household has a weakened immune system, is at increased risk for severe disease, or is unvaccinated. If this applies to you or your household, you might choose to wear a mask regardless of the level of transmission in your area.
•   If you have a condition or are taking medications that weaken your immune system, you may not be fully protected even if you are fully vaccinated. You should continue to take all precautions recommended for unvaccinated people until advised otherwise by your healthcare provider.
•   People who are NOT vaccinated should continue to take steps to protect themselves.

Testing

• All tests work for all variants, but they will not tell you which variant you have.
• As new variants emerge, scientists will continue to evaluate how well tests work.

Types of Variants

Scientists monitor all variants but may classify certain ones as variants of interest, concern, or high consequence based on how easily they spread, how severe their symptoms are, and how they are treated.
Some variants seem to spread more easily and quickly than other variants, which may lead to more cases of COVID-19. An increase in the number of cases will put more strain on healthcare resources, leading to more hospitalizations and potentially more deaths.

Variants of concern (Voc) are variants for which there is evidence of an increase in transmissibility, more severe disease (for example, increased hospitalizations or deaths), significant reduction in neutralization by antibodies generated during previous infection or vaccination, reduced effectiveness of treatments or vaccines, or diagnostic detection failures.
WHO label	Earliest documented samples	Date of documenting	Date of Designation
Beta	South Africa	September 2020	29.12.2020
Gamma	Brazil	December 2020	29.12.2020
Delta	India	December 2020	24.05.2021
Omicron	South Africa	November 2021	27.11.2021
Variants of interest (VOI) are variants with specific genetic markers that have been associated with changes to receptor binding, reduced neutralization by antibodies generated against previous infection or vaccination, reduced efficacy of treatments, potential diagnostic impact, or predicted increase in transmissibility or disease severity.
WHO label	Earliest documented samples	Date of Documenting	Date of Designation
Mu	Columbia	January 2021	29.04.2021
Lambda	Peru	December 2020	22.07.2021
AY.4.2	Great Britain	June 2021	11.11.2021
De-escalated Variants are variants of the virus characterized by at least one of following properties: The variant is no longer circulating. The variant circulated for a long period of time without affecting the global epidemiological situation. Scientific studies demonstrated that the variant is not associated with any concerning property
WHO label	Earliest documented samples	Date of documenting	Date of Designation
Alpha	Great Britain	September 2020	VOC - 29.12.2020 De-escalation - 03.09.2021
Eta	Great Britain/Nigeria	December 2020	VOI` 22.04.2021թ De-escalation - 03.09.2021
Kappa	India	December 2020	VOI - 22.04.2021թ De-escalation -03.09.2021
Iota	USA	December 2020	VUM - 29.04.2021 De-escalation - 03.09.2021
Theta	Philippines	January 2021	VOI - 22.04.2021 De-escalation - 03.09.2021
Zeta	Brazil	January 2021	VUM - 29.04.2021 De-escalation - 03.09.2021
Epsilon	USA	December 2020	VOI - 22.04.2021 De-escalation - 22.07.2021
Alerts for Further Monitoring (VUM) A SARS-CoV-2 variant with genetic changes that are suspected to affect virus characteristics with some indication that it may pose a future risk, but evidence of phenotypic or epidemiological impact is currently unclear, requiring enhanced monitoring and repeat assessment pending new evidence. The current list inclides 9 variants of COVID-19.

Reference list

¹ CDC. Understanding Variant