What is COVID-19

Information about COVID-19 including where the virus came from, how it spreads, current variants of concern including Omicron, and treatments.

About COVID-19

COVID-19 is a disease caused by the coronavirus SARS-CoV-2. It affects your lungs, airways and other organs.

Coronaviruses are a large and diverse family of viruses that cause illnesses such as the common cold. Other recent diseases caused by coronaviruses include severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS).

SARS-CoV-2 was first recognised in China and likely originated in animals. It is still unclear how the virus came to infect humans. The disease spread to other countries, with the World Health Organization (WHO) declaring a pandemic on 11 March 2020.

The virus has since undergone genetic mutations over time as it adapts to humans. Some of these mutations can spread more easily than the original virus.

Variants of COVID-19

It is a natural process for viruses to change or mutate, which may produce variants. Variants are developing around the world. This tends to happen in places where the virus is out of control.

WHO is tracking variants of concern and variants of interest.

Tracking SARS-CoV-2 variants | WHO website (external link)

Variants of COVID-19 may affect how fast the virus spreads, or how sick people get from the virus.

The current circulating variants of concern are:

  • Delta — first found in India
  • Omicron — first found in South Africa.

The Ministry of Health is providing updates on these variants.

COVID-19: About the Delta variant | health.govt.nz (external link)

COVID-19: About the Omicron variant | health.govt.nz (external link)

COVID-19: Science news | health.govt.nz (external link)

About the Omicron variant

Omicron was first classified as a variant of concern by WHO in November 2021. It has spread worldwide and is now the major variant in many countries. It is more transmissible than previous variants of the virus, including Delta. Omicron, like other variants, continues to change. There are now 2 main sub-variants — BA.1 and BA.2. Both of these are circulating in the community, with BA.2 more dominant.

We have a very effective system in place for identifying new variants in New Zealand. The possibility of new variants like Omicron is why we continue to perform whole-genome sequencing on cases from overseas and those not linked to a community cluster.

COVID-19: About the Omicron variant | health.govt.nz (external link)

How Omicron is different from earlier variants

Although Omicron is a new variant, we have already learned a lot from experiences overseas. Compared to Delta, Omicron:

  • is more transmissible
  • causes similar symptoms, but because we have a highly vaccinated population, many people may not have any symptoms, though could still pass the virus on to others 
  • has resulted in many more people being hospitalised than at any other time in the pandemic. This is because Omicron can cause many more infections over a short period of time
  • can still cause severe illness and even death, especially in people who are at high risk of severe outcomes such as older people and those who have underlying health conditions.

How COVID-19 spreads

COVID-19 is usually spread from person to person. When an infected person breathes, speaks, coughs, sneezes or sings, they may spread particles containing the virus.

These particles range in size. Larger and heavier particles — droplets — quickly fall to the ground or other surfaces within seconds or minutes. Smaller particles — aerosols — can remain airborne for minutes to hours. Spread of the virus by aerosols appears to be more important than previously thought.

The risk of airborne transmission becomes higher:

  • in enclosed spaces that do not have good airflow
  • in crowded places with many people nearby
  • in close-contact settings, such as close-range conversations, singing, or shouting.

The risk is lower outside, with fewer people, and if people are widely spread.

How to protect yourself and others

Keeping up healthy habits can slow the spread of the virus and help protect you, your whānau, and your community from COVID-19, including variants. Even if you are vaccinated, you still need to keep up these habits.

Healthy habits

Getting vaccinated means you are far less likely to get really sick and have to go to hospital if you catch COVID-19. You are also less likely to pass COVID-19 on to other people.

While a 2-dose course provides some protection against severe disease from Omicron, protection against infection can decrease over time. A booster will improve protection against Omicron by reducing the chance of more serious infection and the risk of transmitting it to others.

Get your vaccine booster

COVID-19 symptoms

The symptoms of COVID-19 are like common illnesses such as the cold or flu. Some people will only experience mild to moderate symptoms. Older people, ethnic minorities, and those with underlying medical conditions are at higher risk of severe illness from the virus.

Some people who have had the virus are suffering health impacts longer than a few weeks or months. This is commonly referred to as Long COVID.

Symptoms of COVID-19 and Long COVID

People at higher risk of COVID-19

COVID-19 treatments

COVID-19 causes 2 major issues that cause harm when someone is infected — a viral attack on the body and in some cases an immune reaction.

Studies for new treatments cover both issues and concentrate on 3 areas.

  • Antiviral drugs limiting the ability of the virus to thrive in the body.
  • Medicines that calm the immune system over-reaction prompted in some patients.
  • Antibody treatments that help the body fight the virus. 

The Ministry of Health has updates on pharmaceutical treatments for COVID-19.

COVID-19 Science Updates | health.govt.nz (external link)

Pharmac is funding appropriate COVID-19 treatments for New Zealanders. The agency decides which medicines to publicly fund in New Zealand.

Pharmac has secured treatments for COVID-19, including:

  • Baricitinib
  • Ronapreve
  • Remdesivir
  • Tocilizumab
  • Paxlovid
  • Molnupiravir.

Medsafe will assess these medicines before treatment for COVID-19.

Find more information on Pharmac's website:

Pharmac is funding COVID-19 treatments | pharmac.govt.nz (external link)

Our response to COVID-19

Aotearoa New Zealand’s strategy with the COVID-19 Protection Framework (also known as the traffic lights) is for New Zealanders to connect with friends and whānau, while also protecting everyone from serious illness.

We do this through:

  • testing anyone with symptoms
  • hygiene measures such as washing our hands and wearing a face mask
  • testing and tracing potential contacts
  • isolating cases and their contacts.

Traffic lights

New Zealand’s vaccine plan

High rates of vaccination is New Zealand’s key tool in protecting people and minimising the spread of COVID-19, and central to the settings in the framework. The COVID-19 vaccine is free and available to everyone in New Zealand aged 5 and over.

COVID-19 vaccines

Wastewater testing

Wastewater testing is being used as an extra tool to help check for COVID-19 in New Zealand. It is being used as a surveillance tool alongside testing of:

  • symptomatic people in the community
  • asymptomatic testing of workers at the border and in managed isolation and quarantine facilities.

Information on wastewater testing for COVID-19 (external link)

COVID-19 wastewater testing results around the country | esr.cri.nz (external link)

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