Search for COVID-19 and Reopening Information Here

Are there different strains or variants of COVID-19? Are they in New Jersey?

Last Updated: 01/27/2023

Viruses constantly change or mutate, and new variants of a virus are expected to occur overtime. Sometimes new variants emerge and disappear. Other times, new variants emerge and persist.

Some COVID-19 variants, including the Delta and Omicron variants, may spread more easily than other variants.

COVID-19 vaccines are expected to protect against severe illness, hospitalizations, and death due to infection with the Omicron variant. With other variants, like Delta, vaccines have remained effective at preventing severe illness, hospitalizations, and death. The recent emergence of Omicron further emphasizes the importance of vaccination and boosters. Booster doses provide essential protection against the virus.

The NJ Department of Health and the CDC are continuously monitoring variants currently in the United States and closely monitoring information about new variants, including the Omicron variant.

For the latest data on variant cases reported in New Jersey by county, visit the NJ Department of Health's dashboard.

Omicron Variant

The NJ Department of Health is closely monitoring information about the Omicron variant (B.1.1.529). The Omicron variant was designated a "Variant of Concern" by the World Health Organization in November 2021.

The Omicron variant spreads more easily than the original virus that causes COVID-19 and the Delta variant. CDC expects that anyone with Omicron infection can spread the virus to others, even if they are vaccinated or don't have symptoms.

Preliminary data suggest that Omicron may cause more mild disease, although some people may still have severe disease, need hospitalization, and could die from the infection with this variant.

Even if only a small percentage of people with Omicron infection need hospitalization, the large volume of cases could overwhelm the healthcare system which is why it's important to take steps to protect yourself.

Current vaccines are expected to protect against severe illness, hospitalizations, and deaths due to infection with the Omicron variant. However, breakthrough infections in people who are vaccinated are likely to occur. People who are up to date with their COVID-19 vaccines and get COVID-19 are less likely to develop serious illness than those who are unvaccinated and get COVID-19.

For more information, visit the CDC's page on the Omicron variant.

Delta Variant

The Delta variant (B.1.617.2) was first documented in October 2020 and was designated a "Variant of Concern" by the World Health Organization in May 2021.

The Delta variant is highly contagious, more than twice as contagious as previous variants. Some data suggest the Delta variant might cause more severe illness than previous variants.

Vaccines are effective at preventing severe disease and death, including against the Delta variant.

Visit the CDC's page on the Delta variant for more information.

How do I protect myself from these variants?

The best way to protect yourself from the virus is to get a COVID-19 vaccine.

Getting vaccinated makes you:

  • 3.5x less likely to get infected with COVID-19
  • 8x less likely to get ill from COVID-19
  • 25x less likely to be hospitalized or die from COVID-19

If you're already vaccinated, get a bivalent booster shot that targets the Omicron variant. To protect yourself and avoid putting anyone you love at risk, get a bivalent booster shot at any vaccination location. Everyone 6 months and older should get a bivalent booster if it has been at least two months since your most recent booster or primary series. Learn more.

In addition, everyone should wear a mask indoors in public in areas in regions with high COVID-19 transmission, regardless of vaccination status. If you are unvaccinated or at high risk, wear a mask and keep physical distance in indoor and some outdoor spaces.

For more information on how to protect yourself and others, refer to this article.

Source:,may%20become%20harder%20to%20stop.;; Health Commissioner Persichilli's Remarks 11/29/21;