COVID-19 Variants

The Omicron Variant

On November 26, 2021, the World Health Organization (WHO) classified a new variant, B.1.1.529, as a Variant of Concern and has named it Omicron. CDC is following the details of this new variant, first reported to the WHO by South Africa. Among other prevention measures, CDC recommends that everyone 5 years and older protect themselves from COVID-19 by getting fully vaccinated. CDC encourages a COVID-19 vaccine booster dose for those who are eligible. Read the full CDC statement here.

On December 10, 2021, the Rhode Island Department of Health (RIDOH) identified the first case of COVID-19 caused by the Omicron variant. The current data tell us that Omicron is highly contagious. Currently, most COVID-19 cases in Rhode Island are caused by the Omicron variant.

The Delta Variant

What We Know

  • The Delta variant is aggressive, spreads quickly and easily, and may cause more serious illness among people of all ages, including young people.
  • Some vaccinated people can get the Delta variant of COVID-19, but most hospitalizations and deaths continue to be among the unvaccinated.

What We Can Do

  • Data suggest that COVID-19 vaccines help protect you against the Delta variant.
    • Unvaccinated people are most at risk of getting and spreading the Delta variant.
    • Getting vaccinated, wearing a mask, and weekly testing are more important than ever to stop the variant from spreading and to protect the progress we’ve made.
    • Vaccination reduces the risk of severe illness, hospitalization, and death from the Delta variant. Find a vaccine near you at
  • Even if you have mild symptoms of COVID-19 and are up to date on your vaccinations, isolate at home and get tested.
  • COVID-19 treatment can keep you from getting sicker from the Delta variant.
    • COVID-19 is for people who test positive for COVID-19. It helps keep you from getting sicker and being hospitalized. Learn more at

Print and share our Delta variant flyer, a printable version of this information.

What We Know About Variants

  • Viruses change all the time—this is normal and expected. These changes can happen when a virus moves from person to person. When a virus changes, the new version is called a variant. There are multiple variants of the virus that causes COVID-19. Scientists and health and medical experts are studying these variants to understand how changes to the virus affect how it spreads and how it infects people. To better understand what variants are, how they form, and how they spread, listen to this episode of Public Health Out Loud.
  • Variants are found all over the world. The CDC is keeping track of these variants and posts updates to a web page about COVID-19 variants.
  • Some variants spread more easily and quickly than other variants. This means they can cause more cases of COVID-19, which can lead to more hospitalizations and more deaths. Some variants may also impact our treatments, vaccines, and tests. We call these “variants of concern.”
  • COVID-19 variants of concern are now dominant in Rhode Island. RIDOH is monitoring these variants and posting data on the COVID-19 Data Tracker.
  • Data suggest that COVID-19 vaccines authorized for use in the United States offer protection against all current COVID-19 variants.
  • We can all help prevent these variants from spreading by following basic guidance to protect your household. This helps Rhode Island’s families, businesses, and economy. Continue to wear your mask, watch your distance, follow quarantine and isolation requirements, get tested often, and get vaccinated when it’s available to you.

What We Don’t Know About Variants

Scientists are working to learn more about these variants, and more studies are needed to understand:

  • How widely these variants have spread
  • Whether these variants cause milder or more severe disease in people
  • How these variants may affect current treatments, vaccines, and tests

What Rhode Island is Doing

RIDOH State Health Laboratories coordinate the SARS-CoV-2 genomic surveillance program in partnership with the CDC and clinical and academic laboratories. This means we are sequencing and analyzing a representative selection of samples of the virus circulating in the state to identify differences between these samples and the genetic material of the original virus. 

We are sharing the results of these analyses on the Variant page of the COVID-19 Data Tracker.