New variants of COVID-19

New variants of COVID-19 have emerged in several places around the world. The Omicron variant, is now the main variant everywhere, including in New Zealand.

On this page, you can find the following information:

Is it normal for viruses to change?

It is normal for viruses to constantly change. This is known as mutation. These changes create new strains or variants of viruses. Read about why and how viruses change. 

Many variants of the virus that causes COVID-19 have been found around the world during this pandemic and have spread to other countries. They are now named using the Greek alphabet according to the order in which they have been identified. Current known variants are Alpha (identified in the UK), Beta (identified in South Africa), Gamma (identified in Brazil), Delta (identified in India) and Omicron (identified in South Africa).

The Omicron variant is the most transmissible variant, spreading a lot more easily than the original version of the COVID-19 virus and other variants.

What does the Omicron variant mean for Aotearoa New Zealanders?

The Omicron variant has some differences compared to the Delta version of the virus. The main one is the ease with which it is transmitted (passed on), making it more challenging to contain the spread of the virus in an outbreak. 

  • Omicron appears to cause milder symptoms than Delta, at least in vaccinated people. 
  • People who are unvaccinated are likely to experience more severe symptoms than people who are vaccinated.
  • The 5 main symptoms experienced are runny nose, headache, fatigue, sneezing and a sore throat.
  • The chance of infecting others, such as people within your household or other contacts, is even higher than it was with Delta as Omicron is so transmissible.
  • The incubation period (time taken to develop the disease) is about a day shorter with Omicron (3 days) than it was with Delta (4 days).
  • More people may have no symptoms (asymptomatic) when infectious which means they may not know they have it.  

The important thing to remember is that, whatever the variant, it is still COVID-19. So all the advice about how to stop the spread by getting all the vaccinations you are eligible for, isolating, wearing masks and social distancing still applies. 

Although it's going to be harder, you can still help stop the spread of the Omicron variant:

  • Get vaccinated.
  • Stay home if you're sick. If you show any COVID-19 symptoms, get a COVID-19 test.
  • Physically distance with 2m between yourself and others where possible.
  • Wear a face covering or mask if possible, on public transport and indoors in busy places such as supermarkets.
  • Keep indoor rooms well ventilated (eg, by opening windows and doors) where possible.
  • Wash your hands often.
  • Cough or sneeze into your elbow.
  • Clean surfaces regularly.
Read more about stopping the spread.

Does the COVID-19 vaccine work on the COVID-19 Omicron variant?

Yes, being up-to-date with your vaccines protects you against Omicron variant (but that protection is less than for Delta). Up-to-date means that you have had a full set of primary doses plus any booster vaccinations you are currently eligible for. Vaccination will reduce your risk of having serious COVID-19 symptoms if you do get COVID-19. There is some evidence that getting a COVID-19 vaccination (if you are not already vaccinated) can help to aid recovery during long COVID. Read about protection against long COVID.

People who are up-to-date with their vaccines can still become infected with COVID-19 but the risk is much lower than people who are not up-to-date with their vaccines. Protection against infection with either Delta or Omicron decreases over time.


  1. New COVID-19 variants Centers for Disease Control and Prevention, US, 2022
  2. The effects of virus variants on COVID-19 vaccines World Health Organization, 2021
  3. COVID-19 – about the Delta variant Ministry of Health, NZ, 2021
  4. About the omicron variant Ministry of Health, NZ, 2022
  5. Omicron vs Delta – how the 2 variants compare, according to experts and research, US, 2022 
Credits: Health Navigator Editorial Team.