Variant Coronavirus Strain FAQs
Viruses change constantly. Variants happen when a virus’s genes change, or mutate. New variants of a virus are expected to occur over time. Sometimes new variants emerge and disappear. Other times, new variants emerge and persist.
Multiple variants of the virus that causes COVID-19 are circulating globally and within the United States. In collaboration with a SARS-CoV-2 Interagency Group (SIG), CDC established 4 classifications for the SARS-CoV-2 variants: Variant Being Monitored (VBM), Variant of Interest (VOI), Variant of Concern (VOC), and Variant of High Consequence (VOHC).
What you need to know about variants available here.
Understanding Variants information is here.
The Delta (B.1.617.2 and AY.1 sublineages)variant circulating in the United States is classified as a variant of concern.
There are currently 10 Variants Being Monitored. More information is available here.
Currently there are no SARS-CoV-2 variants that rise to the level of high consequence.
Learn more about proportions of variants circulating in the US here.
These variants seem to spread more easily and quickly than other variants, which may lead to more cases of COVID-19.
So far, studies suggest that antibodies generated through vaccination with currently authorized vaccines recognize these variants. This is being closely investigated and more studies are underway.
Rigorous and increased compliance with public health mitigation strategies, such as vaccination, physical distancing, use of masks, and hand hygiene is essential to limit the spread of the virus that causes COVID-19 and protect public health.
Scientists are working to learn more about variants of the virus that causes COVID-19, including:
- How widely these new variants have spread.
- How the disease caused by these new variants differs from the disease caused by other variants that are currently circulating.
- How these variants may affect existing therapies, vaccines, and tests.
The CDC tracks and reports on SARS-CoV-2 variants circulating in the US. Information, including proportions of variants of concern by state, are published on this page.
These variants seem to spread more easily and quickly than other variants, which may lead to more cases of COVID-19. These variants could lead to a spring surge if people don't continue to protect themselves by using the public health measures we know limit transmission. An increase in the number of cases will put more strain on health care resources, lead to more hospitalizations, and potentially more deaths.
We do not yet know how the disease caused by these new variants differs from the disease caused by other variants that have been circulating.
Because of the availability of different types of diagnostic tests, many diagnostic tests can still be reliably used to diagnose the variant strains.
The mutations could potentially decrease the effectiveness of monoclonal antibodies in treating the virus. That is currently being studied.
Testing has shown that the Moderna vaccine may be a little less potent against the South African variant, but showed no reduction in neutralizing antibodies against the others. Moderna is working on a booster specifically designed against this variant.
Dr. Anthony Fauci has said there is a very slight, modest diminution in the efficacy of a vaccine against that variant, but there’s enough cushion with the vaccines that we have that we still consider them to be effective.
Recent results have suggested the AstraZeneca vaccine may not provide much protection against the South African variant.
So far, there’s still enough protection in most other current vaccines to prevent serious illness, hospitalization, and death.
Vaccine effectiveness is being closely investigated, and more studies are underway.
Viruses constantly change through mutation, and new variants of a virus are expected to occur over time. Sometimes new variants emerge and disappear. Other times, new variants emerge and persist.
The same measures that protect against other SARS-CoV-2 variants are effective against the new variants. They include the three W’s -- Wear a mask, Watch your distance, Wash your hands often—even after vaccination, and get vaccinated as soon as the opportunity arises.